Effect of hormone replacement therapy on lipids in perimenopausal and early postmenopausal women

Maturitas 39 (2001) 209– 216 www.elsevier.com/locate/maturitas

Effect of hormone replacement therapy on lipids in perimenopausal and early postmenopausal women Marlies E. Ossewaarde a, Michiel L. Bots a,b,*, Annette A.A. Bak a, Yvonne T. Van Der Schouw a, Jacqueline C.M. Witteman b, Juan Planellas c, Herjan J.T. Coelingh Bennink c, Diederick E. Grobbee a,b a

Julius Center for Patient Oriented Research, Uni6ersity Medical Center Utrecht, Heidelberglaan 100, 3584 CX Utrecht, The Netherlands b Department of Epidemiology and Biostatistics, Erasmus Uni6ersity Medical School, Rotterdam, The Netherlands c Research and De6elopment, NV Organon, Oss, The Netherlands Received 10 October 2000; received in revised form 2 April 2001; accepted 12 April 2001

Abstract Objecti6e: To determine the effects of oral sequential hormone replacement therapy (HRT) on lipid-profile in perimenopausal and early postmenopausal women. Methods: We performed a single-center, randomized, placebo-controlled trial. The trial was double blind with respect to 17b-estradiol/desogestrel (17b-E-D) and placebo and open with respect to conjugated estrogens/norgestrel (CEE-N). A total of 125 healthy perimenopausal and early postmenopausal women, aged 43–58 years, were recruited from the general population in Zoetermeer, the Netherlands. The intervention consisted of 6 months treatment with 1.5 mg 17b-estradiol/0.15 mg desogestrel (n = 53), 0.625 mg conjugated estrogens/0.15 mg norgestrel (n=36) or placebo (n=36). At baseline, cycle 1, 3 and 6, overnight fasting blood samples were obtained in which lipids were determined. We used linear regression analysis to calculate differences in mean change from baseline in lipids in the active treatment groups compared to placebo. Results: In both treatment groups significant (P B 0.05) falls in low-density-lipoprotein (LDL)-cholesterol (17b-E-D: − 7.8% and CEE-N: −8.4%) and lipoprotein(a) (17b-E-D: − 11.7% and CEE-N: −28.3%) were found compared to placebo. Apolipoprotein A1 (17b-E-D: 6.8% and CEE-N: 7.3%) and HDL-cholesterol (17b-E-D: 6.4% and CEE-N: 8.0%) significantly increased compared to placebo. No significant changes were found in the other lipids. Mean changes from baseline in total cholesterol, LDL-cholesterol and apolipoprotein B were significantly more pronounced in postmenopausal women compared to perimenopausal women, adjustment for age-differences did not change the results. Conclusion: Treatment of perimenopausal and early postmenopausal women with 17b-E-D or CEE-N changes their lipid-profile in a potentially anti-atherogenic direction. Changes appear to be more pronounced in postmenopausal women compared to perimenopausal women. © 2001 Elsevier Science Ireland Ltd. All rights reserved. Keywords: Hormone replacement therapy; Lipids; Menopause; Randomized controlled trial

* Corresponding author. Tel.: + 31-30-2509352; fax: + 31-30-2505485. E-mail address: [email protected] (M.L. Bots). 0378-5122/01/$ - see front matter © 2001 Elsevier Science Ireland Ltd. All rights reserved. PII: S 0 3 7 8 - 5 1 2 2 ( 0 1 ) 0 0 2 2 4 - 9

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1. Introduction As compared to men, women are better protected against cardiovascular diseases before the onset of menopause. Estrogens are believed to have protective properties against cardiovascular diseases, but the mechanism of their action is not entirely clear yet. Effects on lipid-profile [1 – 6] as well as direct effects on vascular reactivity [7,8] have been described. Falls in endogenous estrogen levels during menopause coincide with higher levels of total cholesterol, low-density-lipoprotein (LDL-cholesterol) and triglycerides and equal or lower high-density-lipoprotein (HDL-cholesterol) levels in postmenopausal women [5,9]. Hormone replacement therapy (HRT) may favorably affect lipid-profile, especially when only estrogens are used [3,4,10,11]. However, prolonged use of unopposed estrogens increases the risk of endometrial hyperplasia and cancer [12,13]. To prevent this, addition of progestogens is necessary in women with an intact uterus. Unfortunately, beneficial effects of estrogens on cardiovascular risk factors might be attenuated by the addition of progestogens [1,3,4,10,11]. Yet, the overall effect of both unopposed and opposed estrogens supports cardiovascular protection, in spite of some differences between specific drugs [1– 4]. At present, the main reason why women seek HRT is the alleviation of climacteric symptoms [11]. Consequently, many women that receive HRT in practice are perimenopausal or early postmenopausal. Hence, assessment of the effects of HRT on cardiovascular risk factors in this group seems relevant. However, data from randomized controlled trials on HRT and lipids in this specific group of women are rather limited. The purpose of this randomized placebo-controlled trial was to examine the effects of two different combinations of oral sequential HRT on lipid-profile in a group of perimenopausal and early postmenopausal women. 2. Material and methods

2.1. Design We performed a single-center, randomized

placebo-controlled trial. The trial was double blind with respect to a 28-day active treatment with 17b-estradiol/desogestrel (17b-E-D, Liseta®) and placebo and open with respect to a 28-day active treatment with conjugated estrogen/norgestrel (CEE-N, Prempak®). Screening and follow-up took place between January 1996 until February 1997. We randomized 125 perimenopausal and early postmenopausal women. Those women eligible, based on the inclusion criteria, entered the study and received study medication. We randomized to treatment with 17b-E-D (n= 53), CEE-N (n=36), or placebo (n= 36) which is a ratio of 3:2:2. Women visited our clinic at cycle 1, 3 and 6 during intervention (day 259 3). Each strip of 17b-E-D contained 16 tablets with 1.5 mg 17b-estradiol (micronized) and 12 tablets with 1.5 mg 17b-estradiol (micronized)+0.15 mg desogestrel. Placebostrips were matched to 17b-ED strips. Each strip of CEE-N contained 28 tablets with 0.625 mg conjugated estrogens and 12 tablets with 0.15 mg norgestrel. Women in the 17b-E-D or placebo group took one tablet per day, on a continuous basis. Women who received CEE-N took one tablet per day from day 1 to 16 and two tablets per day from day 17 to 28, for each cycle. Tablets were taken after breakfast. The study period comprised six consecutive cycles of 28 days. The institutional review committee approved the study and all women signed informed consent. All procedures followed were in accordance with institutional guidelines.

2.2. Population We recruited women from the general population in Zoetermeer, the Netherlands, by sending a questionnaire on menopause and gynecological issues to all women between 40 and 60 years of age. Women were invited for the screening procedure, when eligible based on the questionnaire and interested to participate in a HRT study. Inclusion criteria were: age between 40 and 60 years, non-hysterectomized, body mass index (BMI) below 29 kg/m2 and written informed consent. Main exclusion criteria were: absence of spontaneous vaginal bleeding for more than 5 years, use of sex-steroids within the last 2 months or hormone implants at

M.E. Ossewaarde et al. / Maturitas 39 (2001) 209–216

any time previously, history or presence of any malignant disorder (excluding history of basal cell carcinoma of the skin), history or presence of cardiovascular or cerebrovascular disease or thrombo-embolism/thrombosis, history or presence of hepatic or renal disease, hypertension (systolic blood pressure\160 mmHg and/or diastolic blood pressure\95 mmHg), significant hyperlipidemia (fasting total cholesterol \8.5 mmol/l and/or fasting triglycerides\ 2.5 mmol/l) and smoking more than 10 cigarettes/day. Drugs influencing hemostasis or carbohydrate metabolism, lipid lowering agents and sex-steroids other than the study medication were not allowed.

2.3. Measurements At baseline and after 1, 3 and 6 cycles, we collected data on age, body weight and body height and calculated BMI. Overnight fasting blood samples were obtained between 08:00 and 10:00 h. Blood was collected with minimal stasis and kept on crushed ice until centrifuged in the laboratory. Plasma was separated by centrifugation at 2100×g for 20 min at 4°C. To obtain ‘platelet-free plasma’ blood was anticoagulated with citrate and centrifuged at 7500× g for 15 min at 4°C. Plasma aliquots were quickly frozen and stored at −80°C for subsequent analysis. Total cholesterol was determined using an enzymatic colorimetric test (CHOD-PAP on Hitachi 747, Boehringer Mannheim). For the measurement of HDL-cholesterol the precipitation method was used, after which dosing took place using the CHOD-PAP method on Hitachi 747 (Boehringer-Mannheim). Triglycerides were measured using an enzymatic colorimetric test (GPOPAP method on Hitachi 747, Boehringer Mannheim). LDL-cholesterol was calculated using the Friedewald-formula [14]. Apolipoprotein A1 and apolipoprotein B were determined using the nefelometric method on BNA Behring. Lipoprotein(a) (Lp(a)) was measured using the ELISA-method (TintElize®). Samples were analyzed in random fashion and biochemical analysts were blinded for the intervention group.

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2.4. Data analysis Data were analyzed according to the intentionto-treat principle. The number of evaluable women at cycle 1, 3 and 6 were 52, 48 and 48 for the 17b-E-D group, 34, 31 and 30 for the CEE-N group and 35, 34 and 34 for the placebo group. To obtain a reliable estimate of the treatment effect, mean lipid levels were calculated using the following formula: ((cycle 1+cycle 3+ cycle 6)/ number of attended cycles). Linear regression was used to compare differences in mean change from baseline in lipids of the 17b-E-D group and CEE-N group with placebo. Differences in mean change from baseline in lipids were also calculated for ‘use of HRT’ (17b-E-D and CEE-N combined) compared to ‘non-use of HRT’ (placebo). Because of the skewed distribution of Lp(a) this parameter was log-transformed. The relative change from baseline (%) was defined as 100*((mean postbaseline value−baseline value)/baseline value). In addition, a stratified analysis was performed for perimenopausal and postmenopausal women. In a multivariate analysis with perimenopausal versus postmenopausal women, adjustments were made for age. A t-test was used to test whether differences between perimenopausal and postmenopausal women were statistically significant. Statistical significance was defined by a two-sided P-level of 0.05. Results are presented as regression coefficients with corresponding 95% confidence intervals. Data were analyzed using SPSS, version 9.0 for Windows.

3. Results From the 125 women randomized, one woman on 17b-E-D, two women on CEE-N and one on placebo had no post-baseline measurements of lipids. Therefore, results are based on 121 women, who had at least one post-baseline lipid assessment. Participants were between 43 and 58 years of age, mean age of 48.5 years, with a standard deviation (S.D.) of 2.7. Table 1 shows the general characteristics of the three groups at baseline. A

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Table 1 Baseline characteristics of the study population

Age (years) Weight (kg) BMI (kg/m2) Total cholesterol (mmol/l) LDL-cholesterol (mmol/l) HDL-cholesterol (mmol/l) Triglycerides (g/l) Apolipoprotein B (g/l) Lp(a) (g/l)a a

17b-E-D (n= 52)

CEE-N (n = 34)

Placebo (n = 35)

48.4 (3.0) 67.4 (9.1) 24.1 (3.0) 5.71 (0.98) 3.60 (0.90) 1.58 (0.36) 1.66 (0.25) 1.01 (0.23) 0.08 (0.05–0.38)

48.7 (2.5) 66.6 (9.7) 24.0 (3.2) 5.44 (1.02) 3.29 (0.91) 1.58 (0.37) 1.66 (0.25) 0.93 (0.27) 0.15 (0.07–0.46)

48.7 (2.5) 66.7 (7.) 24.0 (2.3) 6.00 (0.84) 3.70 (0.69) 1.80 (0.41) 1.81 (0.30) 1.04 (0.23) 0.031 (0.05–0.50)

Because of a skewed distribution the median (interquartile range) is presented. Values are means (S.D.).

total of 76 women (63%) were perimenopausal. Fourteen women (11%) prematurely dropped out of the study: five (9%) in the 17b-E-D group, six (17%) in the CEE-N group and three (8%) in the placebo group, mainly because of unacceptable adverse events (see below). Other reasons for discontinuation were insufficient compliance with the treatment (one woman in the placebo-group) and inability to further participation in the study (one

woman in the 17b-E-D group and one in the CEE-N group). Compliance, as assessed by tablet count and diary-checks, was satisfactory in all three groups with a mean compliance rate of over 90%. Table 2 shows differences in mean change from baseline in both active treatment groups separately and in those groups combined, compared to placebo. Proportional changes from baseline are

Table 2 Differences in mean change from baseline in the 17b-E-D-group, CEE-N group and HRT-group compared to placebo

Total cholesterol (mmol/l) LDL-cholesterol (mmol/l) HDL-cholesterol (mmol/l) Triglycerides (mmol/l) Apolipoprotein A1 (g/l) Apolipoprotein B (g/l) Lp(a) (g/l)

17b-E-D vs. placebo

95% CI‡

CEE-N vs. placebo

95% CI‡

HRT§ vs. placebo

95% CI‡

−0.16

−0.37; 0.06

−0.18

−0.42;0.05

−0.17

−0.37;0.03

−0.28

−0.46; −0.09

−0.30

−0.50; −0.09

−0.29

−0.46;−0.12

0.11

0.01; 0.20

0.13

0.03; 0.23

0.12

0.03;0.20

0.03

−0.12; 0.18

−0.05

−0.21; 0.12

0.00

−0.14;−0.14

0.12

0.04; 0.19

0.12

0.04; 0.21

0.12

0.05;0.19

−0.03

−0.09; 0.04

−0.03

−0.09; 0.04

−0.03

−0.08;0.03

−0.08†

B0.001*

−0.05†

B0.001*

−0.03†

0.02*

* P-value (analysis in which Lp(a) was converted by taking the logarithm of Lp(a) for each individual). Analysis without logarithmic transformation. ‡ Confidence interval. § 17b-E-D and CEE-N combined. †

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Fig. 1. Proportional changes (%) from baseline in lipids.

visualized in Fig. 1. In both active treatment groups, LDL-cholesterol significantly decreased compared to placebo. Also, Lp(a) significantly dropped in both active treatment groups compared to placebo. Largest reductions of Lp(a) levels were observed in those women who had elevated Lp(a) levels at baseline. Apolipoprotein A1 and HDL-cholesterol significantly increased in both active treatment groups compared to the placebo group. When we compared all women on HRT (17bE-D-group combined with CEE-N group) to

those who did not use HRT (placebo-group), observations were similar. Although most effects observed are somewhat stronger for CEE-N than for 17b-E-D, no significant differences between the two active regimens (CEE-N and 17b-E-D) were found. At baseline age, total cholesterol, LDL-cholesterol and apolipoprotein B were significantly different between perimenopausal and postmenopausal women (Table 3). Other lipids and BMI did not significantly differ between the two groups. The proportion of women on HRT

Table 3 Baseline characteristics of perimenopausal versus postmenopausal women

17b-E-D (n = . . .) CEE-N (n =. . .) HRT (n =. . .) Placebo (n =. . .) Age (years) Weight (kg) BMI (kg/m2) Total cholesterol (mmol/l) LDL-cholesterol (mmol/l) HDL-cholesterol (mmol/l) Triglycerides (g/l) Apolipoprotein A1 (g/l) Apolipoprotein B (g/l) Lp(a) (g/l)a

a

Perimenopausal (n =76)

Postmenopausal (n = 45)

T-test (P-value)

36 (47%) 19 (25%) 55 (72%) 21 (28%) 48.3 (2.2) 67.4 (8.3) 24.0 (2.6) 5.49 (0.89) 3.36 (0.76) 1.62 (0.39) 1.10 (0.47) 1.68 (0.28) 0.96 (0.22) 0.25 (0.32) 0.14 (0.05–0.40)

16 (36%) 15 (33%) 31 (69%) 14 (31%) 51.4 (2.6) 66.0 (10.2) 24.0 (3.2) 6.12 (0.99) 3.87 (0.92) 1.68 (0.38) 1.22 (0.67) 1.74 (0.25) 1.07 (0.26) 0.33 (0.35) 0.15 (0.05–0.55)

0.20 0.33 0.69 0.69 B0.001 0.60 0.98 B0.001 0.001 0.39 0.25 0.20 0.009 0.23

Because of a skewed distribution the median (interquartile range) is presented as well. Values are means (S.D.).

M.E. Ossewaarde et al. / Maturitas 39 (2001) 209–216

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(17b-E-D and CEE-N combined) was comparable between perimenopausal and postmenopausal women. The reverse was also true: the proportion of perimenopausal women was comparable between women on HRT and those not using HRT. Table 4 shows that most effects are more pronounced in postmenopausal women, although also present in perimenopausal women. Mean changes from baseline in total cholesterol, LDLcholesterol and apolipoprotein B were significantly different between perimenopausal and postmenopausal women. The rise in apolipoprotein A1 was more pronounced in perimenopausal women. Adjustment for age did not alter the findings.

ment cycles: 45 women in the 17b-E-D group (85%), 30 in the CEE-N group (83%) and 29 in the placebo group (81%). Adverse events in the 17b-E-D group and the CEE-N group were more often classified as drug related than in the placebo group (62, 64 and 53%, respectively). The type and severity of the adverse experiences were consistent with those previously reported with this type of therapy, such as headache, edema, depressive feelings, abdominal pain and nausea. Two of the adverse experiences (one in the 17b-E-D group and one in the CEE-N group) were classified as serious but probably not drug-related.

4. Discussion

3.1. Ad6erse e6ents The two active treatments, respectively 17b-E-D and CEE-N, were tolerated in a similar way. A total of 104 women of the 121 treated reported at least one adverse experience during the six treat-

Treatment with 17b-E-D or CEE-N significantly reduces LDL-cholesterol and Lp(a) in perimenopausal and early postmenopausal women. Furthermore, both treatments significantly increase apolipoprotein A1 and HDL-cholesterol.

Table 4 Differences in mean change from baseline: HRT-group compared to placebo: perimenopausal vs. postmenopausal women Perimenopausal women (n= 76)

HRT§ vs. placebo Total −0.03 cholesterol (mmol/l) LDL-cholesterol −0.16 (mmol/l) HDL-cholesterol 0.11 (mmol/l) Triglycerides 0.05 (mmol/l) Apolipoprotein 0.14 A1 (g/l) Apolipoprotein 0.01 B (g/l) Lp(a) (g/l) −0.03†

95% CI‡

Postmenopausal women (n = 45)

% change HRT§ vs. placebo

95% CI‡

T-test (P-value)¶ % change

−0.24; 019

−0.5

−0.42

−0.78; −0.06

−7.3

0.02

−0.35; 0.04

−4.5

−0.51

−0.81; −0.20

−14.3

0.02

0.00; 0.22

6.7

0.13

−0.02; 0.27

7.6

0.88

−0.10; 0.20

4.2

−0.08

−0.37; 0.20

−7.1

0.37

0.06; 0.22

8.3

0.08

−0.05; 0.21

4.7

0.24

−0.06; 0.08

1.0

−0.09

−8.7

0.02

−31.5†

0.67

0.06*

−10.0†

−0.09†

−0.17; −0.00 0.001*

* P-value (analysis in which Lp(a) was converted by taking the logarithm of Lp(a) for each individual). † Analysis without logarithmic transformation. ‡ Confidence interval. § 17b-E-D and CEE-N combined. ¶ Test to determine whether the observed ß-coefficient is statistically different between perimenopausal and postmenopausal women.

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Most data from randomized controlled trials on the effects of HRT on serum lipids are from studies performed in postmenopausal women. Since HRT is frequently prescribed in perimenopausal and early postmenopausal women, usually to alleviate climacteric symptoms, assessment of the effects on cardiovascular risk factors of HRT in this group is relevant. In general, studies on HRT in postmenopausal women show a decrease in total cholesterol, LDL-cholesterol and Lp(a), an increase in HDL-cholesterol and an increase in apolipoprotein A1 [1– 4,6,9,11,15 – 24], compatible with an anti-atherogenic effect. Our findings agree with these previous reports, though the magnitude of the effects tends to be somewhat smaller. In the present study, changes in lipids were more pronounced among postmenopausal women compared to perimenopausal women. Mean changes from baseline in total cholesterol, LDL-cholesterol and apolipoprotein B were even significantly more pronounced in postmenopausal women compared to perimenopausal women. This may be explained by higher levels of endogenous hormones in perimenopausal women, which may reduce the lipid lowering effect of exogenous sex hormones. Elevated levels of Lp(a) are associated with an increased risk of atherosclerosis [25– 29] and may be considered as an independent risk factor for coronary heart disease (CHD) events in postmenopausal women with known coronary artery disease [30]. The currently used lipid lowering drugs do not appear to reduce Lp(a) levels [31]. In our study, largest reductions of Lp(a) levels were observed in those women who had elevated Lp(a) levels at baseline. This corresponds with other findings in literature [1,19]. Therefore, HRT to reduce cardiovascular risk may be particularly useful in women with high Lp(a) levels. This hypothesis appears to be confirmed by data from the HERS-trial [30]: among women with elevated baseline Lp(a) levels CHD risk appears to decrease after several years of follow-up. Furthermore, the authors suggested that baseline Lp(a) levels might modify the effect of intervention with HRT on CHD events. We found no significant differences between the two active regimens (CEE-N and 17b-E-D). Yet,

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the trial was not designed for comparison of CEE-N with 17b-E-D and therefore underpowered to study this comparison. In conclusion, our findings suggest that treatment of perimenopausal and early postmenopausal women during six months with a combination of 17b-estradiol and desogestrel or conjugated estrogens and norgestrel changes their lipid-profile in a potentially anti-atherogenic direction. These changes appear to be more pronounced in postmenopausal women than in perimenopausal women.

Acknowledgements We are grateful to the participants for their essential contributions in this study. We thank J.J.C. Jonker, MD, J. Huizer, MD, E.T.L. Du¨ rlinger, MD, J.R. Jansen and C.E.H. Stehmann for their help. This study was sponsored by a grant from NV Organon.

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