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The validity of the Menopause Specific Quality of Life Questionnaire in older women
Maturitas 60 (2008) 239–243
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The validity of the Menopause Specific Quality of Life Questionnaire in older women Sujeetha Kulasingam a , Rahim Moineddin b , Jacqueline E. Lewis c , Mary C. Tierney d,∗ a
Geriatric Research Unit, Neurosciences, Sunnybrook Health Sciences Centre, Canada Department of Family and Community Medicine and Department of Public Health Sciences, University of Toronto, and Institute for Clinical Evaluative Sciences, Canada c Department of Family Medicine, University of Calgary, Canada d Geriatric Research Unit, Neurosciences, Sunnybrook Health Sciences Centre, 2075 Bayview Avenue, Toronto, Ontario, Canada M4N 3M5 and Department of Family and Community Medicine, University of Toronto b
a r t i c l e
i n f o
Article history: Received 8 February 2008 Received in revised form 10 June 2008 Accepted 18 July 2008 Keywords: Menopause Specific Quality of Life Questionnaire Validity Validation Quality of life Menopause Measurement
a b s t r a c t Objectives: To examine the validity of the Menopause Specific Quality of Life Questionnaire (MENQOL) domains when used with elderly women. We also determined whether MENQOL domain scores were related to depression and cognitive complaints. Methods: 148 post-menopausal women (60–88 years old), not on hormone replacement therapy, were screened for a randomized control trial examining the effectiveness of hormone replacement therapy in the delay of cognitive impairment. Validation of the psychosocial, physical and sexual domains of MENQOL involved linear regression analysis with the mental component and the physical component of the SF-36, and with marital status, respectively. We used logistic regression analysis to examine the relationship between the above MENQOL domain scores and depression, and linear regression analysis to examine the relationship between these MENQOL domain scores and cognitive complaints. All regression analyses were adjusted for age, education, and whether or not a woman had surgical menopause. Results: We found 44% of the variation in the MENQOL’s physical and psychosocial domain scores could be explained by their respective validation measures, and that 18% of the variation in the sexual domain scores could be explained by marital status. Poor quality of life (QoL) on the physical and psychosocial domains was significantly associated with depressed affect and more cognitive complaints. Conclusions: The results support the validity of the MENQOL physical, psychosocial and sexual domains as QoL measures in elderly women. QoL impairment on the physical and psychosocial MENQOL domains are also related to depression and cognitive complaints. Crown Copyright © 2008 Published by Elsevier Ireland Ltd. All rights reserved.
1. Introduction The Menopause Specific Quality of Life Questionnaire (MENQOL), which was developed on women 47–62 years of age, is a valid, reliable, and responsive self-administered quality of life questionnaire specific to the early post-menopausal period [1,2]. MENQOL consists of 29 items divided into four validated domains (vasomotor, sexual, physical, and psychosocial). The development and initial overview of the psychometric properties of the MENQOL are described elsewhere [1]. MENQOL has been widely used in clinical trials [3–6] and the role of health related risk factors in predicting QoL has been examined using the MENQOL [7]. This
∗ Corresponding author. Tel.: +1 416 480 4291; fax: +1 416 480 6776. E-mail address: [email protected] (M.C. Tierney).
tool has also been translated into over 15 languages [2]. Likewise, it has been used to examine changes in QoL in various populations, such as Asian [8,9], Latin American [7], Australian [4], and chronically mentally ill women [10]. The widespread use of MENQOL in different populations demonstrates its recognition as a useful QoL measure. Additional advantages of using MENQOL are the ease of administration and brevity of this four-domain scale. Little is known about QoL during later post-menopausal years. Given that women can expect to live longer (i.e., the average life expectancy of women in 2002 was 82.1 years of age in Canada [11] and 81 in United Kingdom [12]) and that the average age of menopause in industrialized countries is approximately 51 [13], women may live, on average, 30 years beyond the menopause. Hence, it is important to be able to assess QoL accurately throughout the post-menopausal spectrum. The oldest age group studied in other menopause-related QoL measurements is 70 years of age
0378-5122/$ – see front matter. Crown Copyright © 2008 Published by Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.maturitas.2008.07.002
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[14]. We wanted to establish the validity of the MENQOL domains with older women to determine whether these scales could be used to examine QoL in the late as well as the early post-menopausal period. We also wanted to examine whether QoL as measured by the MENQOL domains provided information about two other important clinical aspects of functioning in older women, i.e., depressed mood and cognitive complaints. We had the opportunity to explore both the validity of the MENQOL domains, and their relationships to depression and cognitive complaints in a sample of elderly women who were screened for, but not yet entered into, a randomized control trial examining the effects of estrogen on cognition. The QoL assessment was a baseline measure of the trial. 2. Materials and methods 2.1. Participants The sample consisted of post-menopausal women, 60 years of age and older, who were screened for the estrogen memory study (EMS) at Sunnybrook Health Sciences Center, University of Toronto, Toronto, Canada. Potential participants within the Greater Toronto area were recruited to the study through advertisements, presentations and display booths in hospitals, seniors’ clubs and retirement homes, and through family physician referrals. Recruitment materials stated that the study was recruiting women with memory problems for a 2-year trial examining the effects of estrogen on memory loss. In addition, participants met the following study criteria: 1. Did not meet criteria for a diagnosis of a dementing disorder or have a history of any conditions that might affect cognitive functioning, e.g., chronic alcohol or drug abuse, stroke, hypoxia, intracranial mass lesions, psychoses, brain trauma, or other neurological diseases. 2. Did not have a medical condition with a probable prognosis of death within 2 years. 3. Did not have any conditions that might be exacerbated by estrogen, including history of breast cancer, endometrial cancer, abnormal mammogram, and abnormal pelvic ultrasound. 4. Did not have congestive heart failure (NYHA Class III and IV). 5. Did not have a recent history of myocardial infarction, bypass surgery, angioplasty or unstable angina within the past year. Women with remote histories of any of these cardiac conditions were admitted to the study only after approval from their family physician. 6. Did not use any mode or dose of hormone replacement therapy within the last 2 years. 7. Fluent in English and could read normal print and hear normal speech. 2.2. Procedures and measures A telephone screen was conducted initially to assess for eligibility criteria (i.e., criteria no. 6 and 7). Thereafter, the eligible women were asked to come to Sunnybrook Health Sciences Centre and provide written consent to participate in the study. Next, women were seen by the study physician for a comprehensive diagnostic workup for dementia (to operationalize criteria no. 1). Women without dementia underwent a mammogram and pelvic ultrasound to assess for criteria no. 3. An additional medical assessment by the study physician ensured that they met all medical related inclusion criteria (i.e., criteria no. 2, 3, 4, and 5). Finally, the eligible women were then administered a series of measures.
The measures relevant to this study are described in the section below. 2.2.1. Construct validity of three MENQOL domains in older women The 29-item MENQOL is divided into four domains: psychosocial (7 items), physical (16 items), sexual (3 items) and vasomotor (3 items). Each item is presented in a similar format where the women are asked to indicate whether they experienced the item within the past month. If they did not experience an item, they are given a score of one. If they experienced the item, they then indicated how bothered they were by the occurrence of the item on a 7-point Likert scale from 2 to 8, ‘not at all bothered’ to ‘extremely bothered’. Thus, higher scores represent poorer QoL. A domain score was calculated for each woman according to the original scoring method [1]. To validate the physical and psychosocial MENQOL domains we used the SF-36, a generic measure of health status that assesses both physical and mental QoL, which has been validated in combined male and female populations, ranging from 64 to 82 years old [15–17]. Note that unlike the MENQOL domains, higher SF-36 component scores represent better QoL. Linear regression was used to validate the MENQOL physical and psychosocial domains with the SF-36 physical and mental component summary scores. Age was included as a covariate (independent variable) in the regression analyses to control for potential cohort effects. Education was included as a covariate to control for its potential effects on quality of life [18]. We also controlled for whether or not a woman had a surgically induced menopause because the early sudden drop in gonadal hormones after surgical menopause may influence QoL in later years [19]. These measures were included as covariates in all linear and logistic regression analysis used in this study. We assessed the validity of the MENQOL’s sexual domain indirectly with marital status. The rationale behind this indirect validation comes from evidence showing that older unmarried women feel they are not likely to be sexually active in the future and thus place less importance on sexuality [20]. Thus, we expected that married women in this sample, who were more likely to have a stable sexual partner compared to unmarried women, would be bothered more (poorer QoL) by the items on the sexual domain (i.e., decrease in sexual desire, vaginal dryness and avoiding intimacy). Linear regression was used to validate the sexual domain with marital status. 2.2.2. MENQOL, depression and cognitive complaints Logistic regression analysis determined the degree to which depression was related to QoL on the MENQOL psychosocial domain. The geriatric depression scale (GDS) has been validated in a population of both men and women older than 55 years of age, and consists of 30 questions with a yes/no response [21]. We used the validated cut-off score of greater than 10 on the GDS to define depression [21]. Linear regression analysis determined the degree to which cognitive complaints were related to QoL on the MENQOL psychosocial domain. To measure participants’ subjective cognitive complaints, we used the 19-item scale from Section H of the Cambridge Examination of Mental Disorders for the Elderly (CAMDEX-H), which has been found to be valid and reliable in a predominantly female population over the age of 65 [22]. This scale asks participants to indicate whether they had difficulty in areas such as remembering short lists of items, remembering recent events, or finding the right word when speaking. Higher scores on the MENQOL indicate a poorer QoL. Likewise, higher scores on the GDS indicate greater depression, and higher scores on the CAMDEX-H represent greater cognitive decline. Statistical significance was defined at the level of p < 0.05. All tests
S. Kulasingam et al. / Maturitas 60 (2008) 239–243 Table 1 Baseline characteristics of study participants (n = 148) Variable
Mean (S.D.)
Age (years) Age at menopause (years)a Education (years) Depression (on GDS)b Cognitive complaints (on CAMDEX-H)c
74.8 (6.9) 48.1 (5.8) 13.1 (3.2) 5.8 (4.7) 3.5 (2.3)
GDS: geriatric depression scale. A higher score on the GDS indicates more depressive affect, with a score >10 indicating depression; CAMDEX-H: The Cambridge Examination of Mental Disorders for the Elderly, Section H. A higher score reflects more complaints. a Age at menopause was determined for 136 subjects. b 147 subjects completed GDS. c 145 subjects completed the CAMDEX-H.
were two-sided. Statistical package SAS version 9.1 (SAS Institute Inc., Cary, NC, USA) was used for the analysis. 3. Results 3.1. Baseline characteristics of study participants Table 1 displays the characteristics of participants who completed the MENQOL. The age at menopause could not be determined for 12 women as each had a pre-menopausal hysterectomy with preserved ovarian function. Of the 136 women for whom the age at menopause could be determined, 108 women had a natural menopause and 28 had a surgically induced menopause (a bilateral oophorectomy). As can be seen in Table 1, the mean score on the CAMDEX-H was 3.5. While there are no published norms for the cognitive subscale of the CAMDEX-H, in a prior study [23] that included a sample of women (n = 18) without neuropsychological impairment who were similar to the women in the present study in age, education and medical status, the mean score on the cognitive subscale was 2.1 (±1.8). Thus, women in the present study had, on average, 1.4 more complaints than our normative sample, which is in keeping with the fact that subjects were recruited into a trial for women with concerns about their memory. 3.2. Construct validity Table 2 displays the results of the linear regression analysis of the validation instruments (and covariates) on three MENQOL domains.
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Our results indicated that better QoL on the SF-36 physical and mental component scores was significantly related to better QoL on the physical and psychosocial domains of the MENQOL. When the SF-36 physical component score increased by one unit, the MENQOL physical domain score decreased by 0.07 units. Performance on the SF-36 physical component accounted for 44% of the variance in the MENQOL physical domain scores. When the SF-36 mental component score increased by one unit, the MENQOL psychosocial domain score decreased by 0.1 units. Performance on the SF-36 mental component accounted for 43.5% of the variance in the MENQOL psychosocial domain scores. When age increased by 1 year, the score for MENQOL physical domain (p = 0.0520), psychosocial domain (p = 0.036), and sexual domain (p = 0.504) decreased by 0.020, 0.025, and 0.007 units, respectively. Thus, SF-36 was strongly correlated with MENQOL even after adjusting for age, education, and menopause type. The linear regression results also indicated that being married was associated with worse QoL on the MENQOL sexual domain; the mean sexual domain scores of married women were on average 0.56 units higher compared to those who were not married. Marital status accounted for 18% of variance in the MENQOL sexual domain scores. Menopause type was a significant covariate in this relationship in that women who had surgical menopause were more likely to have greater QoL complaints on the sexual domain. 3.3. MENQOL, depression and cognitive complaints Table 3 shows the results of the logistic regression analysis examining the relationship between depression and each of the four MENQOL domains. The odds that a woman was depressed on the GDS scale increased 2.23 times when the MENQOL score on the physical domain increased by one unit (95% CI: 1.42–3.51), and the odds ratio increased 2.86 times when the MENQOL score on the psychosocial domain increased by one unit (95% CI: 1.84–4.45). The psychosocial domain scores explained 38% of the variation in whether or not a woman was depressed. The physical domain scores explained 23% of the variation whereas the nonsignificant vasomotor and sexual domains explained only near 10% of the variance. The results of the linear regression analysis examining the relationship between cognitive complaints and QoL as determined by each of the four MENQOL domains can be found in Table 4. The psychosocial domain accounted for the greatest proportion of variance in cognitive complaint scores (R2 = 26.1%) followed by the physical domain (R2 = 18.6%), the vasomotor domain (R2 = 9.1%), and the
Table 2 Results of three linear regression analyses with the MENQOL physical, psychosocial, and sexual domain scores as the dependent variables and the SF-36 physical and psychosocial component scores, marital status, age, education, and menopause type as independent variables (n = 148) Dependent
Independent
Parameter estimate
P
95% CI
R2
MENQOL physical domain
SF-36 physical component scorea Age Education Menopause typeb
−0.070 −0.020 0.004 0.396
<0.0001 0.0520 0.8581 0.0309
−0.082 to −0.058 −0.037 to −0.003 −0.033 to 0.041 0.098 to 0.694
0.440
MENQOL psychosocial domain
SF-36 mental component scorea Age Education Menopause typeb
−0.097 −0.025 0.025 0.290
<0.0001 0.036 0.350 0.165
−0.113 to −0.081 −0.044 to −0.006 −0.018 to 0.068 −0.051 to 0.631
0.435
MENQOL sexual domain
Marital statusc Age Education Menopause typeb
0.561 −0.007 −0.022 0.620
0.0001 0.504 0.305 0.001
0.328 to 0.794 −0.024 to 0.024 −0.058 to 0.014 0.331 to 0.909
0.180
a b c
SF-36 and MENQOL are scored in opposite directions. Menopause type refers to natural or surgical menopause (surgical = 1; natural = 0). Married = 1; not presently married, i.e., divorced, single, widowed = 0.
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Table 3 Results of four logistic regression analyses with depression as the dependent variables and the MENQOL domains, age, education, and menopause type as the independent variables Dependent a
Depression
95% CI
R2
Independent
Odds ratio point estimate
MENQOL physical domain Age Education Menopause typeb
2.233 1.019 0.887 1.076
1.420–3.512 0.950–1.093 0.755–1.041 0.327–3.539
0.227
MENQOL psychosocial domain Age Education Menopause typeb
2.862 1.030 0.860 1.394
1.842–4.448 0.952–1.114 0.717–1.032 0.399–4.868
0.375
MENQOL sexual domain Age Education Menopause typeb
1.161 1.005 0.864 1.785
0.726–1.857 0.938–1.077 0.736–1.015 0.586–5.436
0.088
MENQOL vasomotor domain Age Education Menopause typeb
1.287 1.009 0.869 1.683
0.873–1.897 0.941–1.081 0.740–1.020 0.568–4.981
0.101
CI: confidence intervals. a Depression was measured with the GDS: depressed = 1; not depressed = 0; probability modeled was descending. b Menopause type refers to natural or surgical menopause (surgical = 1; natural = 0).
sexual domain (R2 = 5%). A unit increase on the MENQOL’s psychosocial domain score (poorer psychosocial QoL) was related to an increase of one cognitive complaint on the CAMDEX-H. Likewise, a unit increase on the MENQOL’s physical domain score (poorer physical QoL) was related to one cognitive complaint on the CAMDEX-H. The sexual and vasomotor domain accounted for a much smaller, but nevertheless significant percent of the variation in cognitive complaint scores (see Table 4). Poorer QoL on the sexual and vasomotor domain scores predicted greater cognitive complaints. 4. Discussion This was a cross-sectional study of older women, eligible to participate in a clinical trial, who completed the MENQOL, a QoL measure developed for younger post-menopausal women. The results provide support for the validity of the physical, psychosocial, and sexual domains of the MENQOL in elderly women. This study is the first to explore the validity of a menopause-related
QoL measure in a sample of older post-menopausal women. The validity of the MENQOL domains was demonstrated through strong correlations with the equivalent SF-36 component scales. These relationships were shown even when the covariates of age, education and menopause type were included in the regression models. Of note, surgical menopause was another significant covariate that was related to poorer QoL on two MENQOL domains, suggesting that early changes in hormones following surgical menopause may affect QoL in later years. These findings support the need to include the aforementioned covariates in future studies examining QoL in elderly women. The vasomotor domain, which measures the influence of night sweats, hot flashes and sweating, was not validated in this study. It should be noted that among the 149 participants, only 16 women (11%) endorsed hot flashes, 25 women (17%) endorsed night sweats, and 36 women (24%) endorsed sweating on the vasomotor domain. The frequency of women endorsing all three items on the vasomotor domain was 17.3%. Thus, given the relative infrequency in vasomotor menopausal symptoms in this sample and in other stud-
Table 4 Results of four linear regression analyses with cognitive complaints on the CAMDEX-H as the dependent variables and the MENQOL domains, age, education, and menopause type as the independent variables Dependent a
Cognitive complaints
a b
Independent
Parameter estimate
P
95% CI
R2
MENQOL physical domain Age Education Menopause typeb
0.923 0.042 −0.034 −0.723
<0.0001 0.117 0.502 0.135
0.584–1.261 −0.010 to 0.094 −0.152 to 0.074 −1.666 to 0.219
0.186
MENQOL psychosocial domain Age Education Menopause typeb
0.924 0.043 −0.053 −0.410
<0.0001 0.092 0.338 0.358
0.656–1.193 −0.007 to 0.092 −0.160 to 0.055 −1.282 to 0.462
0.261
MENQOL sexual domain Age Education Menopause typeb
0.474 0.035 −0.062 −0.329
0.037 0.220 0.321 0.528
0.326–0.916 −0.021 to 0.092 −0.184 to 0.060 −1.347 to 0.689
0.050
MENQOL vasomotor domain Age Education Menopause typeb
0.640 0.047 −0.047 −0.454
0.001 0.102 0.442 0.370
0.261–1.020 −0.009 to 0.103 −0.167 to 0.073 −1.445 to 0.536
0.091
Cognitive complaints were measured with CAMDEX-H. Menopause type refers to natural or surgical menopause (surgical = 1; natural = 0).
S. Kulasingam et al. / Maturitas 60 (2008) 239–243
ies of menopausal symptoms in older women [24,25], validation of this domain may not be relevant in older women. All four domains on the MENQOL predicted the likelihood of cognitive complaints, and the physical and psychosocial domains of the MENQOL predicted the likelihood of depression. These findings are important because each domain is brief consisting of only a short number of items. This may be useful in a clinical setting as responses to this brief questionnaire may suggest concurrent problems of depression or perceptions of poor memory. This study is limited in its generalization in that the sample was composed of women who had agreed to participate in a randomized trial examining the effects of estrogen on cognition in women who were concerned about their memory and in relatively good health. Thus, the extent to which the findings apply to less healthy women or women without memory concerns remains to be examined but our findings support further studies. A further limitation of this study was that the sexual domain of the MENQOL was indirectly validated using marital status based on the expectation that married women would be more bothered by the menopausal symptoms of this domain. However, further studies using more direct validation of this domain are required. 5. Conclusions We investigated the validity of the physical, psychosocial and sexual domains of the MENQOL and found them to be valid measures to examine QoL in relatively healthy older women. Poor QoL as assessed by the physical, psychosocial, sexual and vasomotor MENQOL domains were significantly related to cognitive complaints and the physical and psychosocial domains were significantly related to depression, suggesting that scores on these domains of the MENQOL may be indictors of these clinical symptoms. Further studies are needed to address the suggestions raised in this paper. Conflict of interest None declared. Acknowledgement This study was supported by grants from the Canadian Institutes of Health Research, and the Institute of Neurosciences, Mental Health and Addiction (CIHR), and Shire Biochem. The study sponsors had no role in the collection, analysis or interpretation of data and in the writing of the manuscript. References [1] Hilditch J, Lewis J, Peter A, et al. A menopause-specific quality of life questionnaire: development and psychometric properties. Maturitas 1996;24:161–75. [2] Lewis JE, Hilditch JR, Wong CJ. Further psychometric property development of the menopause-specific quality of life questionnaire and development of a modified version, MENQOL-intervention questionnaire. Maturitas 2005;50(March (3)):209–21.
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Maturitas journal homepage: www.elsevier.com/locate/maturitas
The validity of the Menopause Specific Quality of Life Questionnaire in older women Sujeetha Kulasingam a , Rahim Moineddin b , Jacqueline E. Lewis c , Mary C. Tierney d,∗ a
Geriatric Research Unit, Neurosciences, Sunnybrook Health Sciences Centre, Canada Department of Family and Community Medicine and Department of Public Health Sciences, University of Toronto, and Institute for Clinical Evaluative Sciences, Canada c Department of Family Medicine, University of Calgary, Canada d Geriatric Research Unit, Neurosciences, Sunnybrook Health Sciences Centre, 2075 Bayview Avenue, Toronto, Ontario, Canada M4N 3M5 and Department of Family and Community Medicine, University of Toronto b
a r t i c l e
i n f o
Article history: Received 8 February 2008 Received in revised form 10 June 2008 Accepted 18 July 2008 Keywords: Menopause Specific Quality of Life Questionnaire Validity Validation Quality of life Menopause Measurement
a b s t r a c t Objectives: To examine the validity of the Menopause Specific Quality of Life Questionnaire (MENQOL) domains when used with elderly women. We also determined whether MENQOL domain scores were related to depression and cognitive complaints. Methods: 148 post-menopausal women (60–88 years old), not on hormone replacement therapy, were screened for a randomized control trial examining the effectiveness of hormone replacement therapy in the delay of cognitive impairment. Validation of the psychosocial, physical and sexual domains of MENQOL involved linear regression analysis with the mental component and the physical component of the SF-36, and with marital status, respectively. We used logistic regression analysis to examine the relationship between the above MENQOL domain scores and depression, and linear regression analysis to examine the relationship between these MENQOL domain scores and cognitive complaints. All regression analyses were adjusted for age, education, and whether or not a woman had surgical menopause. Results: We found 44% of the variation in the MENQOL’s physical and psychosocial domain scores could be explained by their respective validation measures, and that 18% of the variation in the sexual domain scores could be explained by marital status. Poor quality of life (QoL) on the physical and psychosocial domains was significantly associated with depressed affect and more cognitive complaints. Conclusions: The results support the validity of the MENQOL physical, psychosocial and sexual domains as QoL measures in elderly women. QoL impairment on the physical and psychosocial MENQOL domains are also related to depression and cognitive complaints. Crown Copyright © 2008 Published by Elsevier Ireland Ltd. All rights reserved.
1. Introduction The Menopause Specific Quality of Life Questionnaire (MENQOL), which was developed on women 47–62 years of age, is a valid, reliable, and responsive self-administered quality of life questionnaire specific to the early post-menopausal period [1,2]. MENQOL consists of 29 items divided into four validated domains (vasomotor, sexual, physical, and psychosocial). The development and initial overview of the psychometric properties of the MENQOL are described elsewhere [1]. MENQOL has been widely used in clinical trials [3–6] and the role of health related risk factors in predicting QoL has been examined using the MENQOL [7]. This
∗ Corresponding author. Tel.: +1 416 480 4291; fax: +1 416 480 6776. E-mail address: [email protected] (M.C. Tierney).
tool has also been translated into over 15 languages [2]. Likewise, it has been used to examine changes in QoL in various populations, such as Asian [8,9], Latin American [7], Australian [4], and chronically mentally ill women [10]. The widespread use of MENQOL in different populations demonstrates its recognition as a useful QoL measure. Additional advantages of using MENQOL are the ease of administration and brevity of this four-domain scale. Little is known about QoL during later post-menopausal years. Given that women can expect to live longer (i.e., the average life expectancy of women in 2002 was 82.1 years of age in Canada [11] and 81 in United Kingdom [12]) and that the average age of menopause in industrialized countries is approximately 51 [13], women may live, on average, 30 years beyond the menopause. Hence, it is important to be able to assess QoL accurately throughout the post-menopausal spectrum. The oldest age group studied in other menopause-related QoL measurements is 70 years of age
0378-5122/$ – see front matter. Crown Copyright © 2008 Published by Elsevier Ireland Ltd. All rights reserved. doi:10.1016/j.maturitas.2008.07.002
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[14]. We wanted to establish the validity of the MENQOL domains with older women to determine whether these scales could be used to examine QoL in the late as well as the early post-menopausal period. We also wanted to examine whether QoL as measured by the MENQOL domains provided information about two other important clinical aspects of functioning in older women, i.e., depressed mood and cognitive complaints. We had the opportunity to explore both the validity of the MENQOL domains, and their relationships to depression and cognitive complaints in a sample of elderly women who were screened for, but not yet entered into, a randomized control trial examining the effects of estrogen on cognition. The QoL assessment was a baseline measure of the trial. 2. Materials and methods 2.1. Participants The sample consisted of post-menopausal women, 60 years of age and older, who were screened for the estrogen memory study (EMS) at Sunnybrook Health Sciences Center, University of Toronto, Toronto, Canada. Potential participants within the Greater Toronto area were recruited to the study through advertisements, presentations and display booths in hospitals, seniors’ clubs and retirement homes, and through family physician referrals. Recruitment materials stated that the study was recruiting women with memory problems for a 2-year trial examining the effects of estrogen on memory loss. In addition, participants met the following study criteria: 1. Did not meet criteria for a diagnosis of a dementing disorder or have a history of any conditions that might affect cognitive functioning, e.g., chronic alcohol or drug abuse, stroke, hypoxia, intracranial mass lesions, psychoses, brain trauma, or other neurological diseases. 2. Did not have a medical condition with a probable prognosis of death within 2 years. 3. Did not have any conditions that might be exacerbated by estrogen, including history of breast cancer, endometrial cancer, abnormal mammogram, and abnormal pelvic ultrasound. 4. Did not have congestive heart failure (NYHA Class III and IV). 5. Did not have a recent history of myocardial infarction, bypass surgery, angioplasty or unstable angina within the past year. Women with remote histories of any of these cardiac conditions were admitted to the study only after approval from their family physician. 6. Did not use any mode or dose of hormone replacement therapy within the last 2 years. 7. Fluent in English and could read normal print and hear normal speech. 2.2. Procedures and measures A telephone screen was conducted initially to assess for eligibility criteria (i.e., criteria no. 6 and 7). Thereafter, the eligible women were asked to come to Sunnybrook Health Sciences Centre and provide written consent to participate in the study. Next, women were seen by the study physician for a comprehensive diagnostic workup for dementia (to operationalize criteria no. 1). Women without dementia underwent a mammogram and pelvic ultrasound to assess for criteria no. 3. An additional medical assessment by the study physician ensured that they met all medical related inclusion criteria (i.e., criteria no. 2, 3, 4, and 5). Finally, the eligible women were then administered a series of measures.
The measures relevant to this study are described in the section below. 2.2.1. Construct validity of three MENQOL domains in older women The 29-item MENQOL is divided into four domains: psychosocial (7 items), physical (16 items), sexual (3 items) and vasomotor (3 items). Each item is presented in a similar format where the women are asked to indicate whether they experienced the item within the past month. If they did not experience an item, they are given a score of one. If they experienced the item, they then indicated how bothered they were by the occurrence of the item on a 7-point Likert scale from 2 to 8, ‘not at all bothered’ to ‘extremely bothered’. Thus, higher scores represent poorer QoL. A domain score was calculated for each woman according to the original scoring method [1]. To validate the physical and psychosocial MENQOL domains we used the SF-36, a generic measure of health status that assesses both physical and mental QoL, which has been validated in combined male and female populations, ranging from 64 to 82 years old [15–17]. Note that unlike the MENQOL domains, higher SF-36 component scores represent better QoL. Linear regression was used to validate the MENQOL physical and psychosocial domains with the SF-36 physical and mental component summary scores. Age was included as a covariate (independent variable) in the regression analyses to control for potential cohort effects. Education was included as a covariate to control for its potential effects on quality of life [18]. We also controlled for whether or not a woman had a surgically induced menopause because the early sudden drop in gonadal hormones after surgical menopause may influence QoL in later years [19]. These measures were included as covariates in all linear and logistic regression analysis used in this study. We assessed the validity of the MENQOL’s sexual domain indirectly with marital status. The rationale behind this indirect validation comes from evidence showing that older unmarried women feel they are not likely to be sexually active in the future and thus place less importance on sexuality [20]. Thus, we expected that married women in this sample, who were more likely to have a stable sexual partner compared to unmarried women, would be bothered more (poorer QoL) by the items on the sexual domain (i.e., decrease in sexual desire, vaginal dryness and avoiding intimacy). Linear regression was used to validate the sexual domain with marital status. 2.2.2. MENQOL, depression and cognitive complaints Logistic regression analysis determined the degree to which depression was related to QoL on the MENQOL psychosocial domain. The geriatric depression scale (GDS) has been validated in a population of both men and women older than 55 years of age, and consists of 30 questions with a yes/no response [21]. We used the validated cut-off score of greater than 10 on the GDS to define depression [21]. Linear regression analysis determined the degree to which cognitive complaints were related to QoL on the MENQOL psychosocial domain. To measure participants’ subjective cognitive complaints, we used the 19-item scale from Section H of the Cambridge Examination of Mental Disorders for the Elderly (CAMDEX-H), which has been found to be valid and reliable in a predominantly female population over the age of 65 [22]. This scale asks participants to indicate whether they had difficulty in areas such as remembering short lists of items, remembering recent events, or finding the right word when speaking. Higher scores on the MENQOL indicate a poorer QoL. Likewise, higher scores on the GDS indicate greater depression, and higher scores on the CAMDEX-H represent greater cognitive decline. Statistical significance was defined at the level of p < 0.05. All tests
S. Kulasingam et al. / Maturitas 60 (2008) 239–243 Table 1 Baseline characteristics of study participants (n = 148) Variable
Mean (S.D.)
Age (years) Age at menopause (years)a Education (years) Depression (on GDS)b Cognitive complaints (on CAMDEX-H)c
74.8 (6.9) 48.1 (5.8) 13.1 (3.2) 5.8 (4.7) 3.5 (2.3)
GDS: geriatric depression scale. A higher score on the GDS indicates more depressive affect, with a score >10 indicating depression; CAMDEX-H: The Cambridge Examination of Mental Disorders for the Elderly, Section H. A higher score reflects more complaints. a Age at menopause was determined for 136 subjects. b 147 subjects completed GDS. c 145 subjects completed the CAMDEX-H.
were two-sided. Statistical package SAS version 9.1 (SAS Institute Inc., Cary, NC, USA) was used for the analysis. 3. Results 3.1. Baseline characteristics of study participants Table 1 displays the characteristics of participants who completed the MENQOL. The age at menopause could not be determined for 12 women as each had a pre-menopausal hysterectomy with preserved ovarian function. Of the 136 women for whom the age at menopause could be determined, 108 women had a natural menopause and 28 had a surgically induced menopause (a bilateral oophorectomy). As can be seen in Table 1, the mean score on the CAMDEX-H was 3.5. While there are no published norms for the cognitive subscale of the CAMDEX-H, in a prior study [23] that included a sample of women (n = 18) without neuropsychological impairment who were similar to the women in the present study in age, education and medical status, the mean score on the cognitive subscale was 2.1 (±1.8). Thus, women in the present study had, on average, 1.4 more complaints than our normative sample, which is in keeping with the fact that subjects were recruited into a trial for women with concerns about their memory. 3.2. Construct validity Table 2 displays the results of the linear regression analysis of the validation instruments (and covariates) on three MENQOL domains.
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Our results indicated that better QoL on the SF-36 physical and mental component scores was significantly related to better QoL on the physical and psychosocial domains of the MENQOL. When the SF-36 physical component score increased by one unit, the MENQOL physical domain score decreased by 0.07 units. Performance on the SF-36 physical component accounted for 44% of the variance in the MENQOL physical domain scores. When the SF-36 mental component score increased by one unit, the MENQOL psychosocial domain score decreased by 0.1 units. Performance on the SF-36 mental component accounted for 43.5% of the variance in the MENQOL psychosocial domain scores. When age increased by 1 year, the score for MENQOL physical domain (p = 0.0520), psychosocial domain (p = 0.036), and sexual domain (p = 0.504) decreased by 0.020, 0.025, and 0.007 units, respectively. Thus, SF-36 was strongly correlated with MENQOL even after adjusting for age, education, and menopause type. The linear regression results also indicated that being married was associated with worse QoL on the MENQOL sexual domain; the mean sexual domain scores of married women were on average 0.56 units higher compared to those who were not married. Marital status accounted for 18% of variance in the MENQOL sexual domain scores. Menopause type was a significant covariate in this relationship in that women who had surgical menopause were more likely to have greater QoL complaints on the sexual domain. 3.3. MENQOL, depression and cognitive complaints Table 3 shows the results of the logistic regression analysis examining the relationship between depression and each of the four MENQOL domains. The odds that a woman was depressed on the GDS scale increased 2.23 times when the MENQOL score on the physical domain increased by one unit (95% CI: 1.42–3.51), and the odds ratio increased 2.86 times when the MENQOL score on the psychosocial domain increased by one unit (95% CI: 1.84–4.45). The psychosocial domain scores explained 38% of the variation in whether or not a woman was depressed. The physical domain scores explained 23% of the variation whereas the nonsignificant vasomotor and sexual domains explained only near 10% of the variance. The results of the linear regression analysis examining the relationship between cognitive complaints and QoL as determined by each of the four MENQOL domains can be found in Table 4. The psychosocial domain accounted for the greatest proportion of variance in cognitive complaint scores (R2 = 26.1%) followed by the physical domain (R2 = 18.6%), the vasomotor domain (R2 = 9.1%), and the
Table 2 Results of three linear regression analyses with the MENQOL physical, psychosocial, and sexual domain scores as the dependent variables and the SF-36 physical and psychosocial component scores, marital status, age, education, and menopause type as independent variables (n = 148) Dependent
Independent
Parameter estimate
P
95% CI
R2
MENQOL physical domain
SF-36 physical component scorea Age Education Menopause typeb
−0.070 −0.020 0.004 0.396
<0.0001 0.0520 0.8581 0.0309
−0.082 to −0.058 −0.037 to −0.003 −0.033 to 0.041 0.098 to 0.694
0.440
MENQOL psychosocial domain
SF-36 mental component scorea Age Education Menopause typeb
−0.097 −0.025 0.025 0.290
<0.0001 0.036 0.350 0.165
−0.113 to −0.081 −0.044 to −0.006 −0.018 to 0.068 −0.051 to 0.631
0.435
MENQOL sexual domain
Marital statusc Age Education Menopause typeb
0.561 −0.007 −0.022 0.620
0.0001 0.504 0.305 0.001
0.328 to 0.794 −0.024 to 0.024 −0.058 to 0.014 0.331 to 0.909
0.180
a b c
SF-36 and MENQOL are scored in opposite directions. Menopause type refers to natural or surgical menopause (surgical = 1; natural = 0). Married = 1; not presently married, i.e., divorced, single, widowed = 0.
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Table 3 Results of four logistic regression analyses with depression as the dependent variables and the MENQOL domains, age, education, and menopause type as the independent variables Dependent a
Depression
95% CI
R2
Independent
Odds ratio point estimate
MENQOL physical domain Age Education Menopause typeb
2.233 1.019 0.887 1.076
1.420–3.512 0.950–1.093 0.755–1.041 0.327–3.539
0.227
MENQOL psychosocial domain Age Education Menopause typeb
2.862 1.030 0.860 1.394
1.842–4.448 0.952–1.114 0.717–1.032 0.399–4.868
0.375
MENQOL sexual domain Age Education Menopause typeb
1.161 1.005 0.864 1.785
0.726–1.857 0.938–1.077 0.736–1.015 0.586–5.436
0.088
MENQOL vasomotor domain Age Education Menopause typeb
1.287 1.009 0.869 1.683
0.873–1.897 0.941–1.081 0.740–1.020 0.568–4.981
0.101
CI: confidence intervals. a Depression was measured with the GDS: depressed = 1; not depressed = 0; probability modeled was descending. b Menopause type refers to natural or surgical menopause (surgical = 1; natural = 0).
sexual domain (R2 = 5%). A unit increase on the MENQOL’s psychosocial domain score (poorer psychosocial QoL) was related to an increase of one cognitive complaint on the CAMDEX-H. Likewise, a unit increase on the MENQOL’s physical domain score (poorer physical QoL) was related to one cognitive complaint on the CAMDEX-H. The sexual and vasomotor domain accounted for a much smaller, but nevertheless significant percent of the variation in cognitive complaint scores (see Table 4). Poorer QoL on the sexual and vasomotor domain scores predicted greater cognitive complaints. 4. Discussion This was a cross-sectional study of older women, eligible to participate in a clinical trial, who completed the MENQOL, a QoL measure developed for younger post-menopausal women. The results provide support for the validity of the physical, psychosocial, and sexual domains of the MENQOL in elderly women. This study is the first to explore the validity of a menopause-related
QoL measure in a sample of older post-menopausal women. The validity of the MENQOL domains was demonstrated through strong correlations with the equivalent SF-36 component scales. These relationships were shown even when the covariates of age, education and menopause type were included in the regression models. Of note, surgical menopause was another significant covariate that was related to poorer QoL on two MENQOL domains, suggesting that early changes in hormones following surgical menopause may affect QoL in later years. These findings support the need to include the aforementioned covariates in future studies examining QoL in elderly women. The vasomotor domain, which measures the influence of night sweats, hot flashes and sweating, was not validated in this study. It should be noted that among the 149 participants, only 16 women (11%) endorsed hot flashes, 25 women (17%) endorsed night sweats, and 36 women (24%) endorsed sweating on the vasomotor domain. The frequency of women endorsing all three items on the vasomotor domain was 17.3%. Thus, given the relative infrequency in vasomotor menopausal symptoms in this sample and in other stud-
Table 4 Results of four linear regression analyses with cognitive complaints on the CAMDEX-H as the dependent variables and the MENQOL domains, age, education, and menopause type as the independent variables Dependent a
Cognitive complaints
a b
Independent
Parameter estimate
P
95% CI
R2
MENQOL physical domain Age Education Menopause typeb
0.923 0.042 −0.034 −0.723
<0.0001 0.117 0.502 0.135
0.584–1.261 −0.010 to 0.094 −0.152 to 0.074 −1.666 to 0.219
0.186
MENQOL psychosocial domain Age Education Menopause typeb
0.924 0.043 −0.053 −0.410
<0.0001 0.092 0.338 0.358
0.656–1.193 −0.007 to 0.092 −0.160 to 0.055 −1.282 to 0.462
0.261
MENQOL sexual domain Age Education Menopause typeb
0.474 0.035 −0.062 −0.329
0.037 0.220 0.321 0.528
0.326–0.916 −0.021 to 0.092 −0.184 to 0.060 −1.347 to 0.689
0.050
MENQOL vasomotor domain Age Education Menopause typeb
0.640 0.047 −0.047 −0.454
0.001 0.102 0.442 0.370
0.261–1.020 −0.009 to 0.103 −0.167 to 0.073 −1.445 to 0.536
0.091
Cognitive complaints were measured with CAMDEX-H. Menopause type refers to natural or surgical menopause (surgical = 1; natural = 0).
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ies of menopausal symptoms in older women [24,25], validation of this domain may not be relevant in older women. All four domains on the MENQOL predicted the likelihood of cognitive complaints, and the physical and psychosocial domains of the MENQOL predicted the likelihood of depression. These findings are important because each domain is brief consisting of only a short number of items. This may be useful in a clinical setting as responses to this brief questionnaire may suggest concurrent problems of depression or perceptions of poor memory. This study is limited in its generalization in that the sample was composed of women who had agreed to participate in a randomized trial examining the effects of estrogen on cognition in women who were concerned about their memory and in relatively good health. Thus, the extent to which the findings apply to less healthy women or women without memory concerns remains to be examined but our findings support further studies. A further limitation of this study was that the sexual domain of the MENQOL was indirectly validated using marital status based on the expectation that married women would be more bothered by the menopausal symptoms of this domain. However, further studies using more direct validation of this domain are required. 5. Conclusions We investigated the validity of the physical, psychosocial and sexual domains of the MENQOL and found them to be valid measures to examine QoL in relatively healthy older women. Poor QoL as assessed by the physical, psychosocial, sexual and vasomotor MENQOL domains were significantly related to cognitive complaints and the physical and psychosocial domains were significantly related to depression, suggesting that scores on these domains of the MENQOL may be indictors of these clinical symptoms. Further studies are needed to address the suggestions raised in this paper. Conflict of interest None declared. Acknowledgement This study was supported by grants from the Canadian Institutes of Health Research, and the Institute of Neurosciences, Mental Health and Addiction (CIHR), and Shire Biochem. The study sponsors had no role in the collection, analysis or interpretation of data and in the writing of the manuscript. References [1] Hilditch J, Lewis J, Peter A, et al. A menopause-specific quality of life questionnaire: development and psychometric properties. Maturitas 1996;24:161–75. [2] Lewis JE, Hilditch JR, Wong CJ. Further psychometric property development of the menopause-specific quality of life questionnaire and development of a modified version, MENQOL-intervention questionnaire. Maturitas 2005;50(March (3)):209–21.
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