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Prevalence of menopause symptoms and their association with lifestyle among Finnish middle-aged women
Maturitas 67 (2010) 368–374
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Prevalence of menopause symptoms and their association with lifestyle among Finnish middle-aged women J. Moilanen a,∗ , A.-M. Aalto c , E. Hemminki c , A.R. Aro d , J. Raitanen a,b , R. Luoto b,c a
Tampere School of Public Health, University of Tampere, Tampere FI-33014, Finland UKK Institute for Health Promotion, Tampere, Finland National Institute for Welfare and Health, Helsinki, Finland d University of Southern Denmark, Esbjerg, Denmark b c
a r t i c l e
i n f o
Article history: Received 16 April 2010 Received in revised form 28 July 2010 Accepted 21 August 2010
Keywords: Menopausal symptoms Lifestyle Prevalence Middle-aged women Finnish middle-aged women
a b s t r a c t Background and aim of the study: The aim of this study is to report the prevalence of menopausal symptoms by severity among the Finnish female population and the association of their symptoms with lifestyle (smoking, use of alcohol, physical activity) and body mass index (BMI). Material and methods: Health 2000 is a nationally representative population-based study of Finnish adults. Data were collected by home interview, three self-administered questionnaires and a clinical examination by a physician. This study included women aged 45–64 years (n = 1427). All symptoms included menopause-specific symptoms. Both univariate analysis and a factor analysis based on symptom factors were performed by menopausal group. Multiple regression analysis included each symptom factor as a dependent variable and confounding and lifestyle factors (age, education, smoking, alcohol use, physical activity, BMI, use of hormonal replacement therapy (HRT) and chronic disease status). Results: Over one-third (38%) of the premenopausal, half of the perimenopausal, and 54% of both postmenopausal and hysterectomized women reported bothersome symptoms. The difference between preand perimenopausal women was largest and statistically most significant in the case of back pain and hot flushes. Physically active women reported fewer somatic symptoms than did women with a sedentary lifestyle. Smoking was not related to vasomotor symptoms. Conclusion: Bothersome symptoms are common in midlife, regardless of menopausal status. Inverse association between physical activity and menopausal symptoms needs to be confirmed in randomized trials. © 2010 Elsevier Ireland Ltd. All rights reserved.
1. Introduction Most women experience menopause between 40 and 58 years of age, the median age being 51 years [1]. Typical symptoms at the time of menopause lasting 4–5 years are hot flushes, night sweats, vaginal dryness and sleep disturbance [2–5]. In addition, menopausal women commonly report a variety of other symptoms, including sexual dysfunction, depression, anxiety, memory loss, fatigue, headache, joint pains and weight gain [4] but they may relate to aging as well as menopause itself. Evidence from population-based cohort and cross-sectional studies support associations between menopausal status and vasomotor symptoms, vaginal dryness and sleep disturbance. However, associations between menopause and mood symptoms, cognitive disturbances and somatic complaints are inconclusive [2].
∗ Corresponding author. Tel.: +358 40 190 1661; fax: +358 33 551 6057. E-mail address: jaana.m.moilanen@uta.fi (J. Moilanen). 0378-5122/$ – see front matter © 2010 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.maturitas.2010.08.007
A number of studies have reported the prevalence of symptoms among middle-aged women [6–9]. Populations, questions and symptom scales in earlier studies have been different, which decreases their comparability. Especially how bothersome the symptoms are and how they evolve have rarely been studied. In a large review by the National Institutes of Health [3], 14–51% of premenopausal and 30–80% of peri- and postmenopausal women reported hot flashes and night sweats. Sleep disturbances are common among all menopausal women (occurring in 16–42% of premenopausal, 39–47% of perimenopausal and 35–60% of postmenopausal women). In a Finnish population-based study by Hemminki et al. [8] 28% of women aged 45–64 years reported hot flushes, 38% reported tiredness and 27% different kind of pains (head-, back-, and joint-ache). Observational and cohort studies have found that physically active women report fewer menopausal symptoms and shorter duration of hot flashes than less active women [5,10,11]. However, intervention studies have been inconclusive [12,13]. Both active and passive smoking have been reported to be associated
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with an increased risk of hot flushes during menopausal transition [10,14–17]. Results of cross-sectional studies on alcohol use and vasomotor symptoms in different menopausal stages are mixed [18,14]. It seems that moderate alcohol consumption (fewer than one drink per day) is not associated with vasomotor symptoms. Whether higher doses of alcohol affect the occurrence of hot flushes is unknown [15]. Several studies have reported a greater amount of menopausal symptoms among women with a higher body mass index (BMI) [10,16]. Longitudinal cohort data from the Study of Women’s Health Across the Nation (SWAN) in the United States did show higher rates of vasomotor symptoms among overweight or obese perimenopausal women [19] but results from Australian longitudinal study, Melbourne Women’s Midlife Health Project did not find that body mass index or change in BMI was associated with hot flush experience in any way [20]. The SWAN study results challenged the widely held belief that obesity is protective against vasomotor symptoms, but differences among racial and ethnics groups between these two countries may have an effect as well [10,21]. Studies describing lifestyle factors are important because use of hormone replacement therapy (HRT), despite its effectiveness in vasomotor symptoms, includes risks [22], and a healthy lifestyle could alleviate some of the symptoms without the risks related to HRT use. The aim of the current study is to report descriptive data the prevalence of symptoms and their bothersome among the Finnish middle-aged female population, and the association of menopausal symptoms with lifestyle (smoking, use of alcohol, physical activity) and BMI. In this study we defined bothersome symptoms as symptoms which bother everyday life as a distinction from general symptoms. 2. Materials and methods 2.1. Subjects The data come from a health examination survey entitled Health 2000. It was carried out in Finland between 2000 and 2001 and has been described in detail elsewhere [23,24]. A nationally representative two-stage stratified cluster sample was drawn up of adults aged 30 and over and living in mainland Finland. A total of 7419 subjects (93% of the 7977 subjects originally drawn from the population register) participated in one or more phases of the study. Data collection included an extensive home interview, three self-administered questionnaires and a clinical examination by a physician. The response rate of the home interview was 87.6% and of the first self-administered questionnaire 84.4% among the whole study population. Response rate among women aged 45–64 years was 86.6%. This study included women aged 45–64 years (n = 1427), who had given answers both in the home interview and to the first self-administered questionnaire and whose menopause status was known. Twenty women were excluded because of missing information concerning menstruation and, thus, unclear menopausal status.
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in arms or legs and pain). Second question was: “Do you have had the following general symptoms or complaints in the past 4 weeks?” (ready-made options were: swollen feet, sleep disturbances, nervousness, depression, tiredness, memory problems, burnout, irritability, trembling of hands, heart palpitation) [24]. In total, 23 symptoms included scale concerning perceived severity (bothersome): 1 = not at all, 2 = a little bit, 3 = moderately, 4 = quite a bit and 5 = extremely. The two latter categories (4 and 5) and the other three (1–3) were combined in order to simplify comparisons. Categories 4 and 5 were defined as bothersome. 2.2.2. Lifestyle factors Lifestyle indicators included smoking, alcohol usage, BMI and physical activity. Smoking status was categorized as daily smoking, occasional smoking, quitters and never smokers. Daily smokers and occasional smokers were combined because only 3% of women smoked occasionally. The use of alcohol was classified according to the Finnish Alcohol Programme into 0–9 portions per week, 10–16 portions and >16 portions per week (one portion being 12 g of pure alcohol). The BMI was based on weight and height (kg/m2 ) and was divided into three categories: <25 kg/m2 (normal), 25–29.9 kg/m2 (overweight) and ≥30 kg/m2 (obese). The women’s physical activity status was assessed on the basis of replies to the following questions: ‘How much do you exercise or strain yourself physically in your leisure time?’ The response categories were (1) sedentary (reading, watching television), (2) moderate (walking, cycling and exercising in other ways for at least 4 h per week), (3) active (fitness increasing sport at least three times per week) and (4) competitive sport [24]. There were only nine women in the competitive sport group so they were combined with the exercise group. 2.2.3. Confounding factors The background variables used were sociodemographics (age, education), menopausal status, use of hormone, and having a chronic disease. Age was used both as a continuous and as a categorical variable (the latter classified as 45–49 years; 50–54 years; 55–59 years; 60–64 years). The level of education was classified as basic or as further education which in turn was divided into three categories: primary, secondary or tertiary. Women with a normal, regular menstrual cycle during the past 12 months were classified as premenopausal, women with an irregular menstrual cycle during the past 12 months as perimenopausal, and women whose last menstrual cycle had occurred more than 12 months ago as postmenopausal regardless whether HRT was used or not. Women who had undergone a hysterectomy included women whose uterus had been removed, either with or without the removal of the ovaries. All these women were classified as hysterectomized independent of the ovarial status. The use of hormone replacement therapy (HRT) was divided into three categories—those who had used HRT during the last month (current users), those who had used it earlier (previous users) and those who had never used it. In some additional analysis, the use of HRT was used as a dichotomous variable (current users vs. never/previous users). Chronic diseases were determined by the question: “Do you have any long-term disease, physical defect or disability? (response alternatives: yes/no) [24].
2.2. Variables
2.3. Analysis
2.2.1. Symptoms General symptoms were asked with the following two questions. First question was: “Next we will ask you about your recent symptoms. How much were you bothered or distressed these symptoms?” (ready-made options were: headache, dizziness, chest pain, back pain, nausea, muscle pain, breathing difficulties, hot flashes, numbness, a lump in one’s throat, weakness, heaviness
To characterize the sample in different menopausal phases, proportions of background variables, lifestyle variables and mean age were calculated by menopausal status group. Statistical differences between the menopausal groups were tested with multinominal logistic and logistic regression analyses, where each categorical background and lifestyle variable was used as a dependent variable at the time, and the menopausal status as an independent variable
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(models were adjusted for age). To examine the prevalence of the various symptoms during the menopausal phases, the proportion of each symptom perceived as bothersome (4 or 5 in the severity scale) was computed for each menopausal group. Statistical differences according to menopausal phase were tested by logistic regression models, where each symptom at the time was used as a dependent variable and the menopausal status as an independent variable controlling for age and the use of HRT. The relationships between lifestyle indicators with symptoms were examined by linear regression analyses. Symptoms were used as dependent variables and lifestyle factors as independent variables. In order to reduce the number of dependent variables (23 symptoms) the symptom variables were combined into three symptoms categories based on an exploratory factor analysis for the symptoms items. Factor analysis is a method used to examine potential underlying dimensions which explain the covariation patterns in a group of variables. An exploratory factor analysis was performed for the 23 symptom variables using varimax rotation. The three factor solution fitted the data well (Appendix A). All items had at least one factor loading greater than 0.35 in this solution. Seven items showed highest loading on factor 1, the loadings varying from 0.59 to 0.80. These items (nervousness, depression, irritability, burnout, tiredness, memory problems and sleep disturbances) reflected psychological symptoms. Ten items received highest loadings on the second factor, the factor loadings varying from 0.38 to 0.79. These items (pain, muscle pain, back pain, heaviness in arms or legs, weakness, numbness, dizziness, nausea, swollen feet, headache) reflected somatic and pain symptoms. Finally, six items received highest loadings on the third factor (factor loadings 0.42–0.68). These items (chest pain, heart palpitations, hot flushes, trembling of hands, breathing difficulties, a lump in one’s throat) reflected vasomotor symptoms. Based on these results, three composite symptom scores were computed: psychological (standardized alpha coefficient 0.90), somatic and pain (alpha 0.88) and vasomotor (alpha 0.72) symptoms. The relationships of each lifestyle indicator with these symptom composite scores were first examined by a series of linear regression analyses, where the symptom scores were used as dependent variables, and lifestyle indicators as independent variables, controlling for the background variables (age, education, chronic disease, menopausal status and the use of HRT). Finally, three multiple regression analyses were computed with each symptom summary score as a dependent variable at the time, and all lifestyle and background variables as independent variables simultaneously. The strength of the associations between symptom scores and independent variables is reported as standardized beta values and p-values. The positive beta values showed magnitude of the association between each covariate and symptom factor, which were used as dependent factors. The statistical analyses were performed using the STATA, version 11.0 [25] and SPSS, version 15.0 statistical packages.
3. Results The average age of the postmenopausal women (56.6 years) was nearly 10 years higher than that of the premenopausal women (48.5 years). Older women had lower education than did younger women. Peri- and postmenopausal women were significantly more often (p < 0.001) smokers than premenopausal women (Table 1). There were more sedentary women (27.3%) in the perimenopausal group (p = 0.019) than among premenopausal women. Women with a history of hysterectomy were more often current HRT users than other women (p < 0.001) (Table 1). Almost all women (99%) reported having experienced at least one symptom (regardless of bothersome) (data not shown). More
Table 1 Distribution of background variables and health behaviour of the study population by menopausal group (n = 1427). Pre n = 334
Peri n = 184
Age: mean (SD) 48.4 (2.8) 50.7 (4.6) Education (%) Primary 26.5 36.1 Secondary 30.9 31.2 Tertiary 42.6 32.7 Smoking (%) Never 57.4 52.9 Quitter 21.4 15.6 Smoker 21.2 31.5** Physical activitya (%) Low 18.4 27.3* Medium 59.9 55.9 High 21.7 16.7 b Alcohol portions/week (%) <10 89.6 87.1 10–16 6.9 8.1 >16 3.5 4.8 Body mass index (kg/m2 )c (%) <25 43.1 43.5 25–29.9 33.6 31.6 30+ 23.3 24.9 d Chronic disease (%) No 62.2 47.7 Yes 37.8 52.3* Using hormone replacement therapye (%) Never 62.1 53.5 Current 29.1 33.1 Previous 8.8 13.4
Post n = 666
Hyst n = 243
56.6 (4.9)
54.7 (5.3)
49.7 25.4 24.9**
47.3 26.8 26.0**
64.0 13.6 22.4***
63.5 17.2 19.4
23.3 65.3 11.4**
18.2 71.4 10.4**
92.7 3.8 3.6
92.4 6.3 1.3
30.4 39.1 30.5
34.2 36.4 29.5
41.2 58.9*
34.4 65.6***
53.1 26.2** 20.7
26.2 59.3*** 14.5**
Pre, premenopausal; peri, perimenopausal; post, postmenopausal; hyst, women who have undergone hysterectomy with or without uni- or bilateral oophorectomy. Significance tested in logistic regression models, each covariate separately as dependent factors, adjusting for age. a Missing 11. b Missing 6. c Missing 9. d Missing 1. e Missing 4. * p < 0.05 ** p < 0.01. *** p < 0.001.
than a third of the premenopausal and almost half of the perimenopausal women had suffered from at least one bothersome symptom (Table 2). Among postmenopausal women and women with a history of hysterectomy, these proportions were even larger (53.6% and 53.7%). Premenopausal women suffered from back pain, muscle pain, numbness and hot flushes significantly less often than the other women, after age was taken into account. The difference between pre- and perimenopausal women was the largest and most significant in back pain and hot flushes. In a supplementary analysis, we examined how the use of HRT was related to the prevalence of symptoms among women in different menopausal stages. However, no statistically significant interaction effect between the menopausal status and HRT emerged. In all menopausal groups, women currently using HRT did not differ from non-users in having at least one bothersome symptom. Obese women (BMI > 30 kg/m2 ) reported more psychological (p < 0.001) and vasomotor (p < 0.01) symptoms than did women of normal weight (Table 3). Moderate overweight (25 kg/m2 < BMI < 30 kg/m2 ) was related to more psychological symptoms (p < 0.01) as well. Women with a sedentary lifestyle reported more psychological symptoms, somatic/pain and vasomotor symptoms (p < 0.001) than did women who exercised regularly. Women, who consumed more than 16 portions of alcohol (192 g of pure alcohol) in a week, reported vasomotor symptoms more
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Table 2 Prevalence of bothersome symptoms by menopausal group, proportion (%) of women.
Recent symptoms Headache Dizziness Chest pain Back pain Nausea Muscle pain Breathing difficulties Hot flushes Numbness A lump in one’s throat Weakness Heaviness in arms or legs Pain Symptoms during last 4 weeks Swollen feet Sleep disturbances Nervousness Depression Tiredness Memory problems Burnout Irritability Trembling of hands Heart palpitations Any of symptoms
Premenopausal (n = 334) (%)
Perimenopausal (n = 184) (%)
Postmenopausal (n = 666) (%)
Hysterectomized (n = 243) (%)
9.3 3.0 1.2 8.4 3.6 11.9 2.6 3.4 6.0 0.9 2.4 3.1 8.4
9.4 4.6 1.2 20.0*** 4.9 20.4* 2.3 10.5*** 11.4* 3.2 5.6 5.4 13.2
7.6 6.9 3.4 17.1** 5.6 22.1* 3.4 9.5** 10.3** 2.3 6.3* 6.3 18.0*
11.7 10.0 1.7 24.2*** 10.4* 24.8** 3.3 7.8* 16.6*** 2.0 8.4** 7.5 16.9*
5.5 10.4 5.3 3.9 7.8 2.7 8.3 3.9 0.9 1.5 37.6
6.6 15.5 6.6 4.5 10.7 5.1 12.7 4.3 2.8* 3.3 49.6*
8.3 20.6 8.9* 7.7* 12.2* 7.7 9.7 4.9 0.8 4.9* 53.6**
11.2 17.9 7.9 8.8* 14.9* 7.0 11.6 4.2 0.8 4.2 53.7**
Symptoms perceived as 4 = quite much or 5 = very much (out of a scale from 2 to 5) included. Significance tested by logistic regression models with each symptom separately as dependent factor, menopausal status, age and use of hormone replacement therapy as covariates. Premenopausal group is a reference category in significance testing. * p < 0.05. ** p < 0.01. *** p < 0.001.
often than did women consuming fewer than 10 portions a week. A weak association with smoking quitters and somatic/pain symptoms (p < 0.05) was also found. In order to evaluate the joint effects of multiple covariates, linear regression models including all covariates and each symptom factor as dependent, were performed (Table 4). Psychological symptoms were reported more often by women with lower education level or chronic illness as compared to other women. Women in the premenopausal phase reported fewer psychological symptoms than did perimenopausal women and women who had undergone hysterectomy. Furthermore, psychological symptoms were more common among overweight women (including the obese), women who had a sedentary lifestyle and women who had previously used
HRT. Smoking status or alcohol consumption was not related to psychological symptoms. Somatic/pain symptoms were most often reported by women with chronic diseases. Women engaging in regular physical exercise reported fewer somatic/pain symptoms than did women with a sedentary lifestyle. There were also more somatic/pain symptoms among women who currently used HRT or had used HRT previously. Smoking status, alcohol consumption or BMI was not related to somatic symptoms after all variables were included at the same model. Vasomotor symptoms were more common among women who had primary or secondary education, who reported excessive alcohol consumption (>16 portions/week compared to <10 por-
Table 3 Linear regression analyses for psychological, somatic/pain and vasomotor symptoms as dependent variables. Lifestyle-specific standardized beta coefficients with 95% confidence intervals (CIs) adjusted for background characteristics (age, menopausal status, education, chronic disease, HRT). Lifestyle Smoking Never (ref.) Quitter Smoker Alcohol portion/week <10 (ref.) 10–16 >16 BMI (kg/m2 ) <25 (ref.) 25–29.9 30+ Physical activity High (ref.) Middle Low * ** ***
p < 0.01. p < 0.01. p < 0.001.
PsychologicalBeta (95% CI)
Somatic/painBeta (95% CI)
VasomotorBeta (95% CI)
– 0.03 (−0.02; 0.08) 0.01 (−0.05; 0.07)
– 0.05 (0.001; 0.10)* 0.03 (−0.03; 0.09)
– 0.04 (−0.004; 0.09) 0.03 (−0.02; 0.09)
– −0.03 (−0.07; 0.01) −0.02 (−0.06; 0.03)
– 0.007 (−0.04; 0.05) 0.02 (−0.03; 0.07)
– −0.02 (−0.06; 0.02) 0.07 (0.02; 0.11)**
– 0.08 (0.03; 0.14)** 0.12 (0.07; 0.18)***
– 0.06 (0.003; 0.12)* 0.05 (−0.003; 0.11)
– 0.07 (0.01; 0.12)* 0.08 (0.03; 0.13)**
– 0.03 (−0.03; 0.10) 0.14 (0.06; 0.20)***
– 0.05 (−0.02; 0.11) 0.18 (0.10; 0.27)***
– 0.06 (0.00009; 0.12) 0.15 (0.07; 0.22)***
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Table 4 Multiple linear regression analyses for psychological, somatic/pain and vasomotor symptoms as dependent variables. Three separate full models including all variables in the table. Standardized beta coefficients with 95% confidence intervals (CIs) and explained variance of the model (R2 ).
Menopausal status Pre (ref.) Peri Post Hyst Age 45–49 (ref.) 50–54 55–59 60–64 Education Tertiary (ref.) Secondary Primary Chronic disease No (ref.) Yes Smoking Never (ref.) Quitter Smoker Alcohol portion/week <10 (ref.) 10–16 >16 BMI (kg/m2 ) <25 (ref.) 25–29.9 30+ Physical activity High (ref.) Medium Low Using HRT Never (ref.) Current Previous R2 * ** ***
Psychological symptoms
Somatic/pain symptoms
Vasomotor symptoms
Beta
Beta
Beta
0.06* 0.08 0.07**
−0.03 −0.02 −0.04
95% CI
(0.01 to 0.10) (−0.0 to 0.16) (0.02 to 0.13)
95% CI
0.05 0.09* 0.03
(−0.02 to 0.10) (0.01 to 0.17) (−0.02 to 0.08)
0.09*** 0.16*** 0.08**
95% CI
(0.05 to 0.14) (0.08 to 0.24) (0.03 to 0.13)
(−0.08 to 0.01) (−0.07 to 0.03) (−0.08 to 0.01)
−0.02 0.00 −0.04
(−0.07 to 0.02) (−0.05 to 0.05) (−0.09 to 0.01)
0.05 0.10***
(−0.00 to 0.11) (0.04 to 0.15)
−0.05 −0.02
(−0.11 to 0.01) (−0.08 to 0.04)
0.05* 0.13***
(0.00 to 0.11) (0.07 to 0.18)
0.36***
(0.30 to 0.41)
0.24***
(0.18 to 0.30)
0.21***
(0.17 to 0.26)
0.02 0.02
(−0.03 to 0.08) (−0.04 to 0.07)
0.05 0.02
(−0.02 to 0.10) (−0.04 to 0.07)
0.04 0.03
(−0.01 to 0.08) (−0.03 to 0.08)
−0.03 −0.02
(−0.07 to 0.02) (−0.07 to 0.02)
0.00 0.02
(−0.05 to 0.05) (−0.03 to 0.06)
−0.03 0.07**
(−0.07 to 0.02) (0.02 to 0.12)
0.07** 0.11***
(0.02 to 0.13) (0.06 to 0.17)
0.06 0.04
(−0.02 to 0.12) (−0.02 to 0.10)
0.07* 0.07**
(0.01 to 0.12) (0.02 to 0.12)
0.03 0.12**
(−0.03 to 0.9) (0.05 to 0.18)
0.05 0.18***
(−0.02 to 0.12) (0.10 to 0.27)
0.06* 0.13**
(0.004 to 0.12) (0.05 to 0.21)
0.02 0.05 0.22
(−0.01 to 0.06) (0.00 to 0.10)
0.05* 0.10** 0.11
(0.00 to 0.10) (0.04 to 0.15)
0.00 0.08** 0.15
(−0.04 to 0.05) (0.03 to 0.13)
0.00 −0.01 −0.05
(−0.04 to 0.04) (−0.06 to 0.04) (−0.10 to −0.01)
p < 0.05. p < 0.01. p < 0.001.
tions/week), who were overweight or obese, who had a sedentary lifestyle or only engaged in light physical activity, who had a chronic disease or had previously used HRT. Smoking status was not related to vasomotor symptoms. 4. Discussion The main finding of the study was that women in midlife, alike before, during and after menopause suffer from a variety of psychological and somatic symptoms, and even every second of them consider at least one of the symptoms as bothersome. The most common bothersome symptoms were traditional menopausal symptoms, such as hot flashes but also back pain, muscle pain and numbness. Lifestyle factors, such as overweight, excessive alcohol use and a sedentary lifestyle were associated with symptoms considered as bothersome. The study was based on a comprehensive population-based sample of middle-aged women with a good participation rate (23), which supports the generalizability of the results. The limitation of the study is the cross-sectional design, due to which no causal inferences can be made. We also did not have a menopause-specific symptom scale available in the study. It is partly unclear which symptoms occurring in middle age are menopause-specific and which are related to aging. Longitudinal studies [9,26] have col-
lected information on hormonal status important in menopausal transition and found that vasomotor symptoms, breast tenderness and vaginal dryness changed significantly with menopause, thus being the only menopause-specific symptoms. Even though our scale lacked indicators of vaginal dryness, breast tenderness and the loss of sexual interest, other vasomotor symptoms were included in our list of symptoms. Furthermore, our list of symptoms is very similar to other lists of menopause-specific symptoms, including the same dimension as other studies with the Kupperman index [7] and the Greene climacteric scale [28]. Our list was more general in nature than a list of just menopause-specific symptoms would have been, and thus may have even more public health implications. Every second woman in the peri- or postmenopausal stage in the present study had during the past 4 weeks or recently at least one symptom she considered as bothersome. Bothersome symptoms were thus not restricted to the perimenopausal phase only, but were reported also by pre- and postmenopausal women. Women who have undergone hysterectomy had bothersome symptoms even more often. Peri- or postmenopausal women and hysterectomized women had back or muscle pains, hot flushes, weakness and numbness significantly more often than did premenopausal women. Our results are in line with other studies showing increasing vasomotor symptoms through menopausal transition [26,29].
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Dennerstein et al. [9] study of Australian women showed that number of all symptoms increased during the menopausal transition. Due to our cross-sectional design, we were not able to examine that in our study but number of women who had at least one bothersome symptom was higher among perimenopausal than premenopausal women. In the Samsioe et al. [6] review, the most typical menopausal symptoms were aches and pains and hot flashes, which is consistent with our study. According to our results, a higher body mass index was significantly associated with a higher number of psychological and vasomotor symptoms among middle-aged women. Our finding is in line with earlier cross-sectional studies showing that overweight and obese women generally have more symptoms [26,10], especially vasomotor symptoms [16,18]. Also data from the longitudinal Study of Women Health Across the Nation (SWAN) did show higher rates of vasomotor symptoms among overweight or obese women [27]. However in Australian study Melbourne Women’s Midlife Health Project did not find association with vasomotor symptoms and body mass index or change in BMI [20]. In SWAN and other studies [19,30] changes in body weight were associated with vasomotor symptoms; weight gain has been shown to increase hot flashes and weight loss to decrease them. In SWAN study they also did find that abdominal adiposity was associated with vasomotor symptoms [27]. Differences between results of these two large studies may be explained by racial and ethnic differences. In Australian study 10% of the women had a body mass index above 32 kg/m2 at baseline compared with 32% of the African–Americans and 17% of the non-Hispanic Whites in American cohort study. In our study 27.6% of women had BMI more than 30 kg/m2 which may partly explain the association between obesity and vasomotor symptoms. The racial or ethnic mixture in Finland is different than in America or Australia (although in this study Australian study population was Australian-born white women), because our population is very homogenous and our sample was limited to women born in Finland. Our data did not show statistically significant association between smoking and symptoms when results were adjusted for other lifestyle variables. However, in most other studies, smoking has been associated with an increased risk of hot flushes [10,16,15], perhaps because of its effect on estrogen metabolism. The reason for this discrepancy may be due to overadjustment; after including all lifestyle variables to the same model, collinearity may explain non-significance. Excessive alcohol use (>16 portions/week as defined in the Finnish Alcohol Programme) was related to vasomotor symptoms. Earlier findings concerning alcohol use and vasomotor symptoms are contradictory. Riley et al. [15] found that perimenopausal women who consumed 1–5 alcohol-containing drinks per week reported fewer hot flushes than did women who did not consume any alcohol. On the other hand, Freeman et al. [18] reported that weekly alcohol use is associated with an increase in hot flushes in perimenopausal women. Due to the cross-sectional nature of our data, we are unable to determine any causal associations between symptoms and smoking or alcohol use. Although exercise and physical activity have well-established benefits for general health and well-being, evidence on their role in specific menopausal symptoms is contradictory. Our study confirms the finding that physically active women have fewer menopausal symptoms than have non-active women [11,31], although opposing results [32] or no associations [12] have also been reported. In the study by Col et al. [5] more physical exercise was associated with shorter symptom duration. Only a few randomized clinical trials on exercise and menopausal symptom reduction have been performed. Wilbur et al. [12] concluded that women in the exercise intervention group had fewer vasomotor
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symptoms and improved sleep as compared with the controls. The study by Aiello et al. [13] showed an increase in the severity of hot flushes and a decreased risk of memory problems among the women in the intervention group as compared to controls. Both studies were quite small and not all participants had symptoms at baseline. Randomized clinical trials are needed to further address the effect of physical activity on the symptoms experienced by middle-aged women. This study was a descriptive study in Finnish female population. No causal conclusions about relationships between symptoms and lifestyle factors can be drawn due to the design. Also a third mediating factor, such as pain or stress, could explain the relationships. Our aim was to establish independent cross-sectional associations of various lifestyle factors with symptoms by adjusting them all simultaneously with confounders (sociodemographic factors, health status, etc.) in the multivariate analysis. The menopause cannot be avoided by any woman in middle age. There are many reasons for alleviating bothersome symptoms experienced by half of Finnish women. Although HRT is known to alleviate many menopausal symptoms, it does not influence other symptoms. Furthermore, it is not free of risks and may not improve the users’ quality of life either [33]. Important factors known to affect health in midlife are physical activity and a high body weight. Since both of these factors can be modified, the menopause is a suitable period for lifestyle changes. However, evidence concerning the effect of lifestyle changes on symptom relief or on improving quality of life is weak. More trials in this area are needed before women should consider non-pharmacological treatment of symptoms as a reliable option for alleviating menopausal symptoms.
Contributors Anna-Mari Aalto and Arja R. Aro originated the idea to study. Riitta Luoto, Jaana Moilanen, Anna-Mari Aalto, Arja R. Aro and Elina Hemminki planned the study questions and analysis. Jani Raitanen was responsible for statistical analysis. Jaana Moilanen prepared the first version of the manuscript. All authors (Riitta Luoto, AnnaMari Aalto, Elina Hemminki, Arja R. Aro, Jaana Moilanen and Jani Raitanen) have participated in drafting of manuscript and approved the final manuscript.
Competing interests We declare that there are no competing interests related to the article.
Funding This work was supported by Academy of Finland grant 2007–2010 (decision number 115088).
Ethical approval Health 2000 study has received ethical approval from Uusimaa hospital health district. We have used questionnaire data which did not need a separate ethical approval.
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Appendix A. Factor coefficients of menopause symptoms in rotated solution, n = 1322 Parameter
Nervousness Depression Irritability Burnout Tiredness Memory problems Sleep disturbances Pain Muscle pain Back pain Heaviness in arms or legs Weakness Numbness Dizziness Nausea Swollen feet Headache Chest pain Heart palpitations Trembling of hands Breathing difficulties A lump in one’s throat Hot flushes Variance explained (%)
Factor 1 (psychological) 0.80 0.80 0.78 0.71 0.68 0.62 0.59
0.37 0.44
40.3
Factor 2 (somatic and pain)
Factor 3 (vasomotor)
0.42
0.79 0.78 0.72 0.66 0.63 0.62 0.46 0.43 0.41 0.38
7.2
0.39
0.68 0.65 0.60 0.59 0.55 0.42 5.1
Only factor loadings ≥ 0.35 are shown. For each item the highest loading is shown in bold.
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[11] Ivarsson T, Spetz A-C, Hammar M. Physical exercise and vasomotor symptoms in postmenopausal women. Maturitas 1998;29:139–46. [12] Wilbur J, Miller AM, McDevitt J, Wang E, Miller J. Menopausal status, moderateintensity walking, and symptoms in midlife women. Res Theor Nurs Prac: Int J 2005;19:163–80. [13] Aiello EJ, Yasui Y, Tworoger SS, et al. Effect of a yearlong, moderate-intensity exercise intervention on the occurrence and severity of menopause symptoms in postmenopausal women. Menopause 2004;11:382–8. [14] Gold EB, Block G, Crawford S, et al. Lifestyle and demographic factors in relation to vasomotor symptoms: baseline results from the study of women’s health across the nations. Am J Epidemiol 2004;159:1189–99. [15] Riley EH, Inui TS, Kleinman K, Connelly MT. Differential association of modifiable health behaviors with hot flashes in perimenopausal and post menopausal women. J Gen Intern Med 2004;19:740–6. [16] Whiteman MK, Staropoli CA, Langenberg PW, McCarter RJ, Kjerulff KH, Flaws JA. Smoking, body mass, and hot flashes in midlife women. Obstet Gynecol 2003;101:264–72. [17] Li C, Samsioe G, Borgfeldt C, Lidfeldt J, Agardh CD, Nerbrand C. Menopauserelated symptoms: what are the background factors? A prospective populationbased cohort study of Swedish women (The Women’s Health in Lund Area Study). Am J Obstet Gynecol 2003;189:1646–53. [18] Freeman EW, Sammal MD, Grisso JA, Battistini M, Garcia-Espagna B, Hollander L. Hot flushes in the late reproductive years: risk factors for African American and Caucasian women. J Womens Health Gend Based Med 2001;10:67–76. [19] Thurston R, Sowers MR, Sternfeld B, et al. Gains in body fat and vasomotor symptom reporting over the menopausal transition. The study of women’s health across the nation. Am J Epidemiol 2009;170:766–74. [20] Guthrie JR, Dennerstein L, Taffe JR, Lehert P, Burger HG. Hot flushes during the menopause transition: a longitudinal study in Australian-born women. Menopause 2005;12:460–7. [21] Green R, Santoro N. Menopausal symptoms and ethnicity: the Study of Women’s Health Across the Nation. Womens Health 2009;5:127–33. [22] Writing Group for the Women’s Health Initiative investigators. Risks and benefits of estrogen plus progestin in healthy postmenopausal women: principal results from the Women’s Health Initiative randomized controlled trial. J Am Med Assoc 2002;288:321–533. [23] Aromaa A, Koskinen S, editors. Health and functional capacity in Finland. Baseline results of the Health 2000 Health examination survey. Helsinki: Publications of the National Public Health Institute B12, Helsinki 2004. [24] Heistaro S, editor. Methodology report. Health 2000 Survey. Helsinki: Publications of the National Public Health Institute B26, Helsinki 2008. [25] StataCorp. Stata Statistical Software: Release 11. College Station, TX: StataCorp LP; 2009. [26] Ford K, Sowers M, Crutchfield M, Wilson A, Jannausch M. A longitudinal study of the predictors of prevalence and severity of symptoms commonly associated with menopause. Menopause 2005;12:308–17. [27] Thurston RC, Sowers MR, Chang Y, et al. Adiposity and reporting of vasomotor symptoms among midlife women. The Study of Women’s Health Across the Nation. Am J Epidemiol 2008;167:78–85. [28] Greene JG. Constructing a standard climacteric scale. Maturitas 1998;29:25– 31. [29] Freeman EW, Sammel MD, Lin H, Gracia CR, Kapoor S, Ferdousi T. The role of anxiety and hormonal changes in menopausal hot flashes. Menopause 2005;12:258–66. [30] Van Poppel M, Brown WJ. “It’s my hormones, doctor” does physical activity help with menopausal symptoms? Menopause 2008;5:78–85. [31] Mirzaiinjmabadi K, Anderson D, Barnes M. The relationship between exercise, body mass index and menopausal symptoms in midlife Australian women. Int J Nurs Pract 2006;12:28–34. [32] Whitcomb BW, Whiteman MK, Langenberg P, Flaws JA, Romani WA. Physical activity and risk of hot flashes among women in midlife. J Womens Health 2007;16:124–33. [33] Veerus P, Fischer K, Hovi S-L, Karro H, Rahu M, Hemminki E. Symptom reporting and quality of life in the Estonian Postmenopausal Hormone Therapy Trial. BMC Womens Health 2008;5, doi:10.1186/1472-6874-8-5.
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Maturitas journal homepage: www.elsevier.com/locate/maturitas
Prevalence of menopause symptoms and their association with lifestyle among Finnish middle-aged women J. Moilanen a,∗ , A.-M. Aalto c , E. Hemminki c , A.R. Aro d , J. Raitanen a,b , R. Luoto b,c a
Tampere School of Public Health, University of Tampere, Tampere FI-33014, Finland UKK Institute for Health Promotion, Tampere, Finland National Institute for Welfare and Health, Helsinki, Finland d University of Southern Denmark, Esbjerg, Denmark b c
a r t i c l e
i n f o
Article history: Received 16 April 2010 Received in revised form 28 July 2010 Accepted 21 August 2010
Keywords: Menopausal symptoms Lifestyle Prevalence Middle-aged women Finnish middle-aged women
a b s t r a c t Background and aim of the study: The aim of this study is to report the prevalence of menopausal symptoms by severity among the Finnish female population and the association of their symptoms with lifestyle (smoking, use of alcohol, physical activity) and body mass index (BMI). Material and methods: Health 2000 is a nationally representative population-based study of Finnish adults. Data were collected by home interview, three self-administered questionnaires and a clinical examination by a physician. This study included women aged 45–64 years (n = 1427). All symptoms included menopause-specific symptoms. Both univariate analysis and a factor analysis based on symptom factors were performed by menopausal group. Multiple regression analysis included each symptom factor as a dependent variable and confounding and lifestyle factors (age, education, smoking, alcohol use, physical activity, BMI, use of hormonal replacement therapy (HRT) and chronic disease status). Results: Over one-third (38%) of the premenopausal, half of the perimenopausal, and 54% of both postmenopausal and hysterectomized women reported bothersome symptoms. The difference between preand perimenopausal women was largest and statistically most significant in the case of back pain and hot flushes. Physically active women reported fewer somatic symptoms than did women with a sedentary lifestyle. Smoking was not related to vasomotor symptoms. Conclusion: Bothersome symptoms are common in midlife, regardless of menopausal status. Inverse association between physical activity and menopausal symptoms needs to be confirmed in randomized trials. © 2010 Elsevier Ireland Ltd. All rights reserved.
1. Introduction Most women experience menopause between 40 and 58 years of age, the median age being 51 years [1]. Typical symptoms at the time of menopause lasting 4–5 years are hot flushes, night sweats, vaginal dryness and sleep disturbance [2–5]. In addition, menopausal women commonly report a variety of other symptoms, including sexual dysfunction, depression, anxiety, memory loss, fatigue, headache, joint pains and weight gain [4] but they may relate to aging as well as menopause itself. Evidence from population-based cohort and cross-sectional studies support associations between menopausal status and vasomotor symptoms, vaginal dryness and sleep disturbance. However, associations between menopause and mood symptoms, cognitive disturbances and somatic complaints are inconclusive [2].
∗ Corresponding author. Tel.: +358 40 190 1661; fax: +358 33 551 6057. E-mail address: jaana.m.moilanen@uta.fi (J. Moilanen). 0378-5122/$ – see front matter © 2010 Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.maturitas.2010.08.007
A number of studies have reported the prevalence of symptoms among middle-aged women [6–9]. Populations, questions and symptom scales in earlier studies have been different, which decreases their comparability. Especially how bothersome the symptoms are and how they evolve have rarely been studied. In a large review by the National Institutes of Health [3], 14–51% of premenopausal and 30–80% of peri- and postmenopausal women reported hot flashes and night sweats. Sleep disturbances are common among all menopausal women (occurring in 16–42% of premenopausal, 39–47% of perimenopausal and 35–60% of postmenopausal women). In a Finnish population-based study by Hemminki et al. [8] 28% of women aged 45–64 years reported hot flushes, 38% reported tiredness and 27% different kind of pains (head-, back-, and joint-ache). Observational and cohort studies have found that physically active women report fewer menopausal symptoms and shorter duration of hot flashes than less active women [5,10,11]. However, intervention studies have been inconclusive [12,13]. Both active and passive smoking have been reported to be associated
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with an increased risk of hot flushes during menopausal transition [10,14–17]. Results of cross-sectional studies on alcohol use and vasomotor symptoms in different menopausal stages are mixed [18,14]. It seems that moderate alcohol consumption (fewer than one drink per day) is not associated with vasomotor symptoms. Whether higher doses of alcohol affect the occurrence of hot flushes is unknown [15]. Several studies have reported a greater amount of menopausal symptoms among women with a higher body mass index (BMI) [10,16]. Longitudinal cohort data from the Study of Women’s Health Across the Nation (SWAN) in the United States did show higher rates of vasomotor symptoms among overweight or obese perimenopausal women [19] but results from Australian longitudinal study, Melbourne Women’s Midlife Health Project did not find that body mass index or change in BMI was associated with hot flush experience in any way [20]. The SWAN study results challenged the widely held belief that obesity is protective against vasomotor symptoms, but differences among racial and ethnics groups between these two countries may have an effect as well [10,21]. Studies describing lifestyle factors are important because use of hormone replacement therapy (HRT), despite its effectiveness in vasomotor symptoms, includes risks [22], and a healthy lifestyle could alleviate some of the symptoms without the risks related to HRT use. The aim of the current study is to report descriptive data the prevalence of symptoms and their bothersome among the Finnish middle-aged female population, and the association of menopausal symptoms with lifestyle (smoking, use of alcohol, physical activity) and BMI. In this study we defined bothersome symptoms as symptoms which bother everyday life as a distinction from general symptoms. 2. Materials and methods 2.1. Subjects The data come from a health examination survey entitled Health 2000. It was carried out in Finland between 2000 and 2001 and has been described in detail elsewhere [23,24]. A nationally representative two-stage stratified cluster sample was drawn up of adults aged 30 and over and living in mainland Finland. A total of 7419 subjects (93% of the 7977 subjects originally drawn from the population register) participated in one or more phases of the study. Data collection included an extensive home interview, three self-administered questionnaires and a clinical examination by a physician. The response rate of the home interview was 87.6% and of the first self-administered questionnaire 84.4% among the whole study population. Response rate among women aged 45–64 years was 86.6%. This study included women aged 45–64 years (n = 1427), who had given answers both in the home interview and to the first self-administered questionnaire and whose menopause status was known. Twenty women were excluded because of missing information concerning menstruation and, thus, unclear menopausal status.
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in arms or legs and pain). Second question was: “Do you have had the following general symptoms or complaints in the past 4 weeks?” (ready-made options were: swollen feet, sleep disturbances, nervousness, depression, tiredness, memory problems, burnout, irritability, trembling of hands, heart palpitation) [24]. In total, 23 symptoms included scale concerning perceived severity (bothersome): 1 = not at all, 2 = a little bit, 3 = moderately, 4 = quite a bit and 5 = extremely. The two latter categories (4 and 5) and the other three (1–3) were combined in order to simplify comparisons. Categories 4 and 5 were defined as bothersome. 2.2.2. Lifestyle factors Lifestyle indicators included smoking, alcohol usage, BMI and physical activity. Smoking status was categorized as daily smoking, occasional smoking, quitters and never smokers. Daily smokers and occasional smokers were combined because only 3% of women smoked occasionally. The use of alcohol was classified according to the Finnish Alcohol Programme into 0–9 portions per week, 10–16 portions and >16 portions per week (one portion being 12 g of pure alcohol). The BMI was based on weight and height (kg/m2 ) and was divided into three categories: <25 kg/m2 (normal), 25–29.9 kg/m2 (overweight) and ≥30 kg/m2 (obese). The women’s physical activity status was assessed on the basis of replies to the following questions: ‘How much do you exercise or strain yourself physically in your leisure time?’ The response categories were (1) sedentary (reading, watching television), (2) moderate (walking, cycling and exercising in other ways for at least 4 h per week), (3) active (fitness increasing sport at least three times per week) and (4) competitive sport [24]. There were only nine women in the competitive sport group so they were combined with the exercise group. 2.2.3. Confounding factors The background variables used were sociodemographics (age, education), menopausal status, use of hormone, and having a chronic disease. Age was used both as a continuous and as a categorical variable (the latter classified as 45–49 years; 50–54 years; 55–59 years; 60–64 years). The level of education was classified as basic or as further education which in turn was divided into three categories: primary, secondary or tertiary. Women with a normal, regular menstrual cycle during the past 12 months were classified as premenopausal, women with an irregular menstrual cycle during the past 12 months as perimenopausal, and women whose last menstrual cycle had occurred more than 12 months ago as postmenopausal regardless whether HRT was used or not. Women who had undergone a hysterectomy included women whose uterus had been removed, either with or without the removal of the ovaries. All these women were classified as hysterectomized independent of the ovarial status. The use of hormone replacement therapy (HRT) was divided into three categories—those who had used HRT during the last month (current users), those who had used it earlier (previous users) and those who had never used it. In some additional analysis, the use of HRT was used as a dichotomous variable (current users vs. never/previous users). Chronic diseases were determined by the question: “Do you have any long-term disease, physical defect or disability? (response alternatives: yes/no) [24].
2.2. Variables
2.3. Analysis
2.2.1. Symptoms General symptoms were asked with the following two questions. First question was: “Next we will ask you about your recent symptoms. How much were you bothered or distressed these symptoms?” (ready-made options were: headache, dizziness, chest pain, back pain, nausea, muscle pain, breathing difficulties, hot flashes, numbness, a lump in one’s throat, weakness, heaviness
To characterize the sample in different menopausal phases, proportions of background variables, lifestyle variables and mean age were calculated by menopausal status group. Statistical differences between the menopausal groups were tested with multinominal logistic and logistic regression analyses, where each categorical background and lifestyle variable was used as a dependent variable at the time, and the menopausal status as an independent variable
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(models were adjusted for age). To examine the prevalence of the various symptoms during the menopausal phases, the proportion of each symptom perceived as bothersome (4 or 5 in the severity scale) was computed for each menopausal group. Statistical differences according to menopausal phase were tested by logistic regression models, where each symptom at the time was used as a dependent variable and the menopausal status as an independent variable controlling for age and the use of HRT. The relationships between lifestyle indicators with symptoms were examined by linear regression analyses. Symptoms were used as dependent variables and lifestyle factors as independent variables. In order to reduce the number of dependent variables (23 symptoms) the symptom variables were combined into three symptoms categories based on an exploratory factor analysis for the symptoms items. Factor analysis is a method used to examine potential underlying dimensions which explain the covariation patterns in a group of variables. An exploratory factor analysis was performed for the 23 symptom variables using varimax rotation. The three factor solution fitted the data well (Appendix A). All items had at least one factor loading greater than 0.35 in this solution. Seven items showed highest loading on factor 1, the loadings varying from 0.59 to 0.80. These items (nervousness, depression, irritability, burnout, tiredness, memory problems and sleep disturbances) reflected psychological symptoms. Ten items received highest loadings on the second factor, the factor loadings varying from 0.38 to 0.79. These items (pain, muscle pain, back pain, heaviness in arms or legs, weakness, numbness, dizziness, nausea, swollen feet, headache) reflected somatic and pain symptoms. Finally, six items received highest loadings on the third factor (factor loadings 0.42–0.68). These items (chest pain, heart palpitations, hot flushes, trembling of hands, breathing difficulties, a lump in one’s throat) reflected vasomotor symptoms. Based on these results, three composite symptom scores were computed: psychological (standardized alpha coefficient 0.90), somatic and pain (alpha 0.88) and vasomotor (alpha 0.72) symptoms. The relationships of each lifestyle indicator with these symptom composite scores were first examined by a series of linear regression analyses, where the symptom scores were used as dependent variables, and lifestyle indicators as independent variables, controlling for the background variables (age, education, chronic disease, menopausal status and the use of HRT). Finally, three multiple regression analyses were computed with each symptom summary score as a dependent variable at the time, and all lifestyle and background variables as independent variables simultaneously. The strength of the associations between symptom scores and independent variables is reported as standardized beta values and p-values. The positive beta values showed magnitude of the association between each covariate and symptom factor, which were used as dependent factors. The statistical analyses were performed using the STATA, version 11.0 [25] and SPSS, version 15.0 statistical packages.
3. Results The average age of the postmenopausal women (56.6 years) was nearly 10 years higher than that of the premenopausal women (48.5 years). Older women had lower education than did younger women. Peri- and postmenopausal women were significantly more often (p < 0.001) smokers than premenopausal women (Table 1). There were more sedentary women (27.3%) in the perimenopausal group (p = 0.019) than among premenopausal women. Women with a history of hysterectomy were more often current HRT users than other women (p < 0.001) (Table 1). Almost all women (99%) reported having experienced at least one symptom (regardless of bothersome) (data not shown). More
Table 1 Distribution of background variables and health behaviour of the study population by menopausal group (n = 1427). Pre n = 334
Peri n = 184
Age: mean (SD) 48.4 (2.8) 50.7 (4.6) Education (%) Primary 26.5 36.1 Secondary 30.9 31.2 Tertiary 42.6 32.7 Smoking (%) Never 57.4 52.9 Quitter 21.4 15.6 Smoker 21.2 31.5** Physical activitya (%) Low 18.4 27.3* Medium 59.9 55.9 High 21.7 16.7 b Alcohol portions/week (%) <10 89.6 87.1 10–16 6.9 8.1 >16 3.5 4.8 Body mass index (kg/m2 )c (%) <25 43.1 43.5 25–29.9 33.6 31.6 30+ 23.3 24.9 d Chronic disease (%) No 62.2 47.7 Yes 37.8 52.3* Using hormone replacement therapye (%) Never 62.1 53.5 Current 29.1 33.1 Previous 8.8 13.4
Post n = 666
Hyst n = 243
56.6 (4.9)
54.7 (5.3)
49.7 25.4 24.9**
47.3 26.8 26.0**
64.0 13.6 22.4***
63.5 17.2 19.4
23.3 65.3 11.4**
18.2 71.4 10.4**
92.7 3.8 3.6
92.4 6.3 1.3
30.4 39.1 30.5
34.2 36.4 29.5
41.2 58.9*
34.4 65.6***
53.1 26.2** 20.7
26.2 59.3*** 14.5**
Pre, premenopausal; peri, perimenopausal; post, postmenopausal; hyst, women who have undergone hysterectomy with or without uni- or bilateral oophorectomy. Significance tested in logistic regression models, each covariate separately as dependent factors, adjusting for age. a Missing 11. b Missing 6. c Missing 9. d Missing 1. e Missing 4. * p < 0.05 ** p < 0.01. *** p < 0.001.
than a third of the premenopausal and almost half of the perimenopausal women had suffered from at least one bothersome symptom (Table 2). Among postmenopausal women and women with a history of hysterectomy, these proportions were even larger (53.6% and 53.7%). Premenopausal women suffered from back pain, muscle pain, numbness and hot flushes significantly less often than the other women, after age was taken into account. The difference between pre- and perimenopausal women was the largest and most significant in back pain and hot flushes. In a supplementary analysis, we examined how the use of HRT was related to the prevalence of symptoms among women in different menopausal stages. However, no statistically significant interaction effect between the menopausal status and HRT emerged. In all menopausal groups, women currently using HRT did not differ from non-users in having at least one bothersome symptom. Obese women (BMI > 30 kg/m2 ) reported more psychological (p < 0.001) and vasomotor (p < 0.01) symptoms than did women of normal weight (Table 3). Moderate overweight (25 kg/m2 < BMI < 30 kg/m2 ) was related to more psychological symptoms (p < 0.01) as well. Women with a sedentary lifestyle reported more psychological symptoms, somatic/pain and vasomotor symptoms (p < 0.001) than did women who exercised regularly. Women, who consumed more than 16 portions of alcohol (192 g of pure alcohol) in a week, reported vasomotor symptoms more
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Table 2 Prevalence of bothersome symptoms by menopausal group, proportion (%) of women.
Recent symptoms Headache Dizziness Chest pain Back pain Nausea Muscle pain Breathing difficulties Hot flushes Numbness A lump in one’s throat Weakness Heaviness in arms or legs Pain Symptoms during last 4 weeks Swollen feet Sleep disturbances Nervousness Depression Tiredness Memory problems Burnout Irritability Trembling of hands Heart palpitations Any of symptoms
Premenopausal (n = 334) (%)
Perimenopausal (n = 184) (%)
Postmenopausal (n = 666) (%)
Hysterectomized (n = 243) (%)
9.3 3.0 1.2 8.4 3.6 11.9 2.6 3.4 6.0 0.9 2.4 3.1 8.4
9.4 4.6 1.2 20.0*** 4.9 20.4* 2.3 10.5*** 11.4* 3.2 5.6 5.4 13.2
7.6 6.9 3.4 17.1** 5.6 22.1* 3.4 9.5** 10.3** 2.3 6.3* 6.3 18.0*
11.7 10.0 1.7 24.2*** 10.4* 24.8** 3.3 7.8* 16.6*** 2.0 8.4** 7.5 16.9*
5.5 10.4 5.3 3.9 7.8 2.7 8.3 3.9 0.9 1.5 37.6
6.6 15.5 6.6 4.5 10.7 5.1 12.7 4.3 2.8* 3.3 49.6*
8.3 20.6 8.9* 7.7* 12.2* 7.7 9.7 4.9 0.8 4.9* 53.6**
11.2 17.9 7.9 8.8* 14.9* 7.0 11.6 4.2 0.8 4.2 53.7**
Symptoms perceived as 4 = quite much or 5 = very much (out of a scale from 2 to 5) included. Significance tested by logistic regression models with each symptom separately as dependent factor, menopausal status, age and use of hormone replacement therapy as covariates. Premenopausal group is a reference category in significance testing. * p < 0.05. ** p < 0.01. *** p < 0.001.
often than did women consuming fewer than 10 portions a week. A weak association with smoking quitters and somatic/pain symptoms (p < 0.05) was also found. In order to evaluate the joint effects of multiple covariates, linear regression models including all covariates and each symptom factor as dependent, were performed (Table 4). Psychological symptoms were reported more often by women with lower education level or chronic illness as compared to other women. Women in the premenopausal phase reported fewer psychological symptoms than did perimenopausal women and women who had undergone hysterectomy. Furthermore, psychological symptoms were more common among overweight women (including the obese), women who had a sedentary lifestyle and women who had previously used
HRT. Smoking status or alcohol consumption was not related to psychological symptoms. Somatic/pain symptoms were most often reported by women with chronic diseases. Women engaging in regular physical exercise reported fewer somatic/pain symptoms than did women with a sedentary lifestyle. There were also more somatic/pain symptoms among women who currently used HRT or had used HRT previously. Smoking status, alcohol consumption or BMI was not related to somatic symptoms after all variables were included at the same model. Vasomotor symptoms were more common among women who had primary or secondary education, who reported excessive alcohol consumption (>16 portions/week compared to <10 por-
Table 3 Linear regression analyses for psychological, somatic/pain and vasomotor symptoms as dependent variables. Lifestyle-specific standardized beta coefficients with 95% confidence intervals (CIs) adjusted for background characteristics (age, menopausal status, education, chronic disease, HRT). Lifestyle Smoking Never (ref.) Quitter Smoker Alcohol portion/week <10 (ref.) 10–16 >16 BMI (kg/m2 ) <25 (ref.) 25–29.9 30+ Physical activity High (ref.) Middle Low * ** ***
p < 0.01. p < 0.01. p < 0.001.
PsychologicalBeta (95% CI)
Somatic/painBeta (95% CI)
VasomotorBeta (95% CI)
– 0.03 (−0.02; 0.08) 0.01 (−0.05; 0.07)
– 0.05 (0.001; 0.10)* 0.03 (−0.03; 0.09)
– 0.04 (−0.004; 0.09) 0.03 (−0.02; 0.09)
– −0.03 (−0.07; 0.01) −0.02 (−0.06; 0.03)
– 0.007 (−0.04; 0.05) 0.02 (−0.03; 0.07)
– −0.02 (−0.06; 0.02) 0.07 (0.02; 0.11)**
– 0.08 (0.03; 0.14)** 0.12 (0.07; 0.18)***
– 0.06 (0.003; 0.12)* 0.05 (−0.003; 0.11)
– 0.07 (0.01; 0.12)* 0.08 (0.03; 0.13)**
– 0.03 (−0.03; 0.10) 0.14 (0.06; 0.20)***
– 0.05 (−0.02; 0.11) 0.18 (0.10; 0.27)***
– 0.06 (0.00009; 0.12) 0.15 (0.07; 0.22)***
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Table 4 Multiple linear regression analyses for psychological, somatic/pain and vasomotor symptoms as dependent variables. Three separate full models including all variables in the table. Standardized beta coefficients with 95% confidence intervals (CIs) and explained variance of the model (R2 ).
Menopausal status Pre (ref.) Peri Post Hyst Age 45–49 (ref.) 50–54 55–59 60–64 Education Tertiary (ref.) Secondary Primary Chronic disease No (ref.) Yes Smoking Never (ref.) Quitter Smoker Alcohol portion/week <10 (ref.) 10–16 >16 BMI (kg/m2 ) <25 (ref.) 25–29.9 30+ Physical activity High (ref.) Medium Low Using HRT Never (ref.) Current Previous R2 * ** ***
Psychological symptoms
Somatic/pain symptoms
Vasomotor symptoms
Beta
Beta
Beta
0.06* 0.08 0.07**
−0.03 −0.02 −0.04
95% CI
(0.01 to 0.10) (−0.0 to 0.16) (0.02 to 0.13)
95% CI
0.05 0.09* 0.03
(−0.02 to 0.10) (0.01 to 0.17) (−0.02 to 0.08)
0.09*** 0.16*** 0.08**
95% CI
(0.05 to 0.14) (0.08 to 0.24) (0.03 to 0.13)
(−0.08 to 0.01) (−0.07 to 0.03) (−0.08 to 0.01)
−0.02 0.00 −0.04
(−0.07 to 0.02) (−0.05 to 0.05) (−0.09 to 0.01)
0.05 0.10***
(−0.00 to 0.11) (0.04 to 0.15)
−0.05 −0.02
(−0.11 to 0.01) (−0.08 to 0.04)
0.05* 0.13***
(0.00 to 0.11) (0.07 to 0.18)
0.36***
(0.30 to 0.41)
0.24***
(0.18 to 0.30)
0.21***
(0.17 to 0.26)
0.02 0.02
(−0.03 to 0.08) (−0.04 to 0.07)
0.05 0.02
(−0.02 to 0.10) (−0.04 to 0.07)
0.04 0.03
(−0.01 to 0.08) (−0.03 to 0.08)
−0.03 −0.02
(−0.07 to 0.02) (−0.07 to 0.02)
0.00 0.02
(−0.05 to 0.05) (−0.03 to 0.06)
−0.03 0.07**
(−0.07 to 0.02) (0.02 to 0.12)
0.07** 0.11***
(0.02 to 0.13) (0.06 to 0.17)
0.06 0.04
(−0.02 to 0.12) (−0.02 to 0.10)
0.07* 0.07**
(0.01 to 0.12) (0.02 to 0.12)
0.03 0.12**
(−0.03 to 0.9) (0.05 to 0.18)
0.05 0.18***
(−0.02 to 0.12) (0.10 to 0.27)
0.06* 0.13**
(0.004 to 0.12) (0.05 to 0.21)
0.02 0.05 0.22
(−0.01 to 0.06) (0.00 to 0.10)
0.05* 0.10** 0.11
(0.00 to 0.10) (0.04 to 0.15)
0.00 0.08** 0.15
(−0.04 to 0.05) (0.03 to 0.13)
0.00 −0.01 −0.05
(−0.04 to 0.04) (−0.06 to 0.04) (−0.10 to −0.01)
p < 0.05. p < 0.01. p < 0.001.
tions/week), who were overweight or obese, who had a sedentary lifestyle or only engaged in light physical activity, who had a chronic disease or had previously used HRT. Smoking status was not related to vasomotor symptoms. 4. Discussion The main finding of the study was that women in midlife, alike before, during and after menopause suffer from a variety of psychological and somatic symptoms, and even every second of them consider at least one of the symptoms as bothersome. The most common bothersome symptoms were traditional menopausal symptoms, such as hot flashes but also back pain, muscle pain and numbness. Lifestyle factors, such as overweight, excessive alcohol use and a sedentary lifestyle were associated with symptoms considered as bothersome. The study was based on a comprehensive population-based sample of middle-aged women with a good participation rate (23), which supports the generalizability of the results. The limitation of the study is the cross-sectional design, due to which no causal inferences can be made. We also did not have a menopause-specific symptom scale available in the study. It is partly unclear which symptoms occurring in middle age are menopause-specific and which are related to aging. Longitudinal studies [9,26] have col-
lected information on hormonal status important in menopausal transition and found that vasomotor symptoms, breast tenderness and vaginal dryness changed significantly with menopause, thus being the only menopause-specific symptoms. Even though our scale lacked indicators of vaginal dryness, breast tenderness and the loss of sexual interest, other vasomotor symptoms were included in our list of symptoms. Furthermore, our list of symptoms is very similar to other lists of menopause-specific symptoms, including the same dimension as other studies with the Kupperman index [7] and the Greene climacteric scale [28]. Our list was more general in nature than a list of just menopause-specific symptoms would have been, and thus may have even more public health implications. Every second woman in the peri- or postmenopausal stage in the present study had during the past 4 weeks or recently at least one symptom she considered as bothersome. Bothersome symptoms were thus not restricted to the perimenopausal phase only, but were reported also by pre- and postmenopausal women. Women who have undergone hysterectomy had bothersome symptoms even more often. Peri- or postmenopausal women and hysterectomized women had back or muscle pains, hot flushes, weakness and numbness significantly more often than did premenopausal women. Our results are in line with other studies showing increasing vasomotor symptoms through menopausal transition [26,29].
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Dennerstein et al. [9] study of Australian women showed that number of all symptoms increased during the menopausal transition. Due to our cross-sectional design, we were not able to examine that in our study but number of women who had at least one bothersome symptom was higher among perimenopausal than premenopausal women. In the Samsioe et al. [6] review, the most typical menopausal symptoms were aches and pains and hot flashes, which is consistent with our study. According to our results, a higher body mass index was significantly associated with a higher number of psychological and vasomotor symptoms among middle-aged women. Our finding is in line with earlier cross-sectional studies showing that overweight and obese women generally have more symptoms [26,10], especially vasomotor symptoms [16,18]. Also data from the longitudinal Study of Women Health Across the Nation (SWAN) did show higher rates of vasomotor symptoms among overweight or obese women [27]. However in Australian study Melbourne Women’s Midlife Health Project did not find association with vasomotor symptoms and body mass index or change in BMI [20]. In SWAN and other studies [19,30] changes in body weight were associated with vasomotor symptoms; weight gain has been shown to increase hot flashes and weight loss to decrease them. In SWAN study they also did find that abdominal adiposity was associated with vasomotor symptoms [27]. Differences between results of these two large studies may be explained by racial and ethnic differences. In Australian study 10% of the women had a body mass index above 32 kg/m2 at baseline compared with 32% of the African–Americans and 17% of the non-Hispanic Whites in American cohort study. In our study 27.6% of women had BMI more than 30 kg/m2 which may partly explain the association between obesity and vasomotor symptoms. The racial or ethnic mixture in Finland is different than in America or Australia (although in this study Australian study population was Australian-born white women), because our population is very homogenous and our sample was limited to women born in Finland. Our data did not show statistically significant association between smoking and symptoms when results were adjusted for other lifestyle variables. However, in most other studies, smoking has been associated with an increased risk of hot flushes [10,16,15], perhaps because of its effect on estrogen metabolism. The reason for this discrepancy may be due to overadjustment; after including all lifestyle variables to the same model, collinearity may explain non-significance. Excessive alcohol use (>16 portions/week as defined in the Finnish Alcohol Programme) was related to vasomotor symptoms. Earlier findings concerning alcohol use and vasomotor symptoms are contradictory. Riley et al. [15] found that perimenopausal women who consumed 1–5 alcohol-containing drinks per week reported fewer hot flushes than did women who did not consume any alcohol. On the other hand, Freeman et al. [18] reported that weekly alcohol use is associated with an increase in hot flushes in perimenopausal women. Due to the cross-sectional nature of our data, we are unable to determine any causal associations between symptoms and smoking or alcohol use. Although exercise and physical activity have well-established benefits for general health and well-being, evidence on their role in specific menopausal symptoms is contradictory. Our study confirms the finding that physically active women have fewer menopausal symptoms than have non-active women [11,31], although opposing results [32] or no associations [12] have also been reported. In the study by Col et al. [5] more physical exercise was associated with shorter symptom duration. Only a few randomized clinical trials on exercise and menopausal symptom reduction have been performed. Wilbur et al. [12] concluded that women in the exercise intervention group had fewer vasomotor
373
symptoms and improved sleep as compared with the controls. The study by Aiello et al. [13] showed an increase in the severity of hot flushes and a decreased risk of memory problems among the women in the intervention group as compared to controls. Both studies were quite small and not all participants had symptoms at baseline. Randomized clinical trials are needed to further address the effect of physical activity on the symptoms experienced by middle-aged women. This study was a descriptive study in Finnish female population. No causal conclusions about relationships between symptoms and lifestyle factors can be drawn due to the design. Also a third mediating factor, such as pain or stress, could explain the relationships. Our aim was to establish independent cross-sectional associations of various lifestyle factors with symptoms by adjusting them all simultaneously with confounders (sociodemographic factors, health status, etc.) in the multivariate analysis. The menopause cannot be avoided by any woman in middle age. There are many reasons for alleviating bothersome symptoms experienced by half of Finnish women. Although HRT is known to alleviate many menopausal symptoms, it does not influence other symptoms. Furthermore, it is not free of risks and may not improve the users’ quality of life either [33]. Important factors known to affect health in midlife are physical activity and a high body weight. Since both of these factors can be modified, the menopause is a suitable period for lifestyle changes. However, evidence concerning the effect of lifestyle changes on symptom relief or on improving quality of life is weak. More trials in this area are needed before women should consider non-pharmacological treatment of symptoms as a reliable option for alleviating menopausal symptoms.
Contributors Anna-Mari Aalto and Arja R. Aro originated the idea to study. Riitta Luoto, Jaana Moilanen, Anna-Mari Aalto, Arja R. Aro and Elina Hemminki planned the study questions and analysis. Jani Raitanen was responsible for statistical analysis. Jaana Moilanen prepared the first version of the manuscript. All authors (Riitta Luoto, AnnaMari Aalto, Elina Hemminki, Arja R. Aro, Jaana Moilanen and Jani Raitanen) have participated in drafting of manuscript and approved the final manuscript.
Competing interests We declare that there are no competing interests related to the article.
Funding This work was supported by Academy of Finland grant 2007–2010 (decision number 115088).
Ethical approval Health 2000 study has received ethical approval from Uusimaa hospital health district. We have used questionnaire data which did not need a separate ethical approval.
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Appendix A. Factor coefficients of menopause symptoms in rotated solution, n = 1322 Parameter
Nervousness Depression Irritability Burnout Tiredness Memory problems Sleep disturbances Pain Muscle pain Back pain Heaviness in arms or legs Weakness Numbness Dizziness Nausea Swollen feet Headache Chest pain Heart palpitations Trembling of hands Breathing difficulties A lump in one’s throat Hot flushes Variance explained (%)
Factor 1 (psychological) 0.80 0.80 0.78 0.71 0.68 0.62 0.59
0.37 0.44
40.3
Factor 2 (somatic and pain)
Factor 3 (vasomotor)
0.42
0.79 0.78 0.72 0.66 0.63 0.62 0.46 0.43 0.41 0.38
7.2
0.39
0.68 0.65 0.60 0.59 0.55 0.42 5.1
Only factor loadings ≥ 0.35 are shown. For each item the highest loading is shown in bold.
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