Early risk of cardiovascular events after commencing hormone replacement therapy

Hormone therapy use in the Canadian Longitudinal Study on Aging: a cross-sectional analysis

OBJECTIVE

The aim of the study was to assess the prevalence and factors associated with hormone therapy (HT) use among Canadian women.

METHODS

Baseline data from the Tracking cohort of the Canadian Longitudinal Study on Aging (CLSA) was used for this analysis. The main outcome was HT use among women aged 45-85 years, defined as current, past, and never users. Multinomial logistic regression models were used to examine the differences between current, past, and never HT users in terms of sociodemographic, health behavior, and health-related variables.

RESULTS

Overall, 9.5% of the sample reported current use of HT, whereas 21.9% reported past use. The main factors associated with a lower likelihood of current HT use were older age (>80 y), nonwhite ethnic background, current employment, regular smoking, obesity, and breast cancer. By contrast, alcohol consumption, and the presence of allergies or mood disorders were positively associated with current HT use.

CONCLUSIONS

These findings provide a recent national picture of HT use in Canada that may be used to inform opportunities for improved physician-patient communication regarding menopause management.

Extracellular matrix integrity: a possible mechanism for differential clinical effects among selective estrogen receptor modulators and estrogens?

Recent gene microarray studies have illustrated heterogeneity in gene expression changes not only between estrogens and selective estrogen receptor modulators (SERMs), but also across different SERM molecules. In ovariectomized rats, this phenomenon was observed with respect to a number of genes involved in collagen turnover and extracellular matrix (ECM) integrity in the uterus and vaginal tissues. Preliminary mechanistic data suggest that these effects on ECM integrity may have relevance in the context of the effect of estrogens and some SERMs to increase the risk of pelvic organ prolapse and the incidence of urinary incontinence in postmenopausal women. Given the pivotal role of ECM integrity and collagen turnover in other tissues and disease states, these processes may provide a fruitful target for future research into the mechanisms for the heterogeneous pharmacology of estrogens and SERMs across different cell types and target tissues.

The effect of hormone therapy and raloxifene on serum matrix metalloproteinase-2 and -9 in postmenopausal women

OBJECTIVE

The aim of the study was to investigate the effect of continuous-combined hormone therapy and raloxifene on the total and active forms of serum matrix metalloproteinase (MMP) -2 and -9.

DESIGN

The study was double-blinded, with a placebo run-in period of 28 to 50 days. Twenty-eight women received either 17beta-estradiol 2 mg + norethisterone acetate 1 mg (E2/NETA) or raloxifene HCL 60 mg for a period of 6 months. Total and active forms of MMP-2 and -9 were estimated at baseline and at month 6.

RESULTS

Total MMP-2 increased significantly in both E2/NETA and raloxifene groups (raloxifene baseline: 278.1 +/- 18.1 ng/mL; 6 months: 303.1 +/- 29.9 ng/mL, P = 0.008) (E2/NETA baseline: 281.9 +/- 27.5 ng/mL; 6 months: 298.8 +/- 12.7 ng/mL, P = 0.025). Similarly, both treatments increased the active MMP-2 fraction, although only the raloxifene-associated increase acquired significance (raloxifene baseline: 24.9 +/- 8.6 ng/mL; 6 months: 31.6 +/- 15.3 ng/mL, P = 0.045) (E2/NETA baseline: 21.7 +/- 5.7 ng/mL; 6 months: 27.4 +/- 5.8 ng/mL, P = 0.128). Total as well as active fractions of MMP-9 were not significantly affected by either treatment.

CONCLUSIONS

Both E2/NETA and raloxifene increased the total and active MMP-2 serum levels. MMP-9 was not significantly affected by either regimen. Larger, long-term clinical trials are needed to elucidate the effect of HT and raloxifene on MMPs and the possible clinical implications for cardiovascular health.

Estrogen Plus Progestin Therapy

The surprising results of the Women's Health Initiative (WHI) reported in 2002 had a profound effect on women as well as health care practitioners. The WHI was the largest, randomized clinical trial designed to determine if postmenopausal hormone use prevented cardiovascular disease as well as other age-related disorders in women. While observational studies suggested that postmenopausal use of estrogen could decrease cardiovascular risk by 40% to 50%, the WHI demonstrated that use of continuous-combined estrogen plus progestin was not cardioprotective and was even associated with increased health risks. The estrogen alone trial of the WHI is still in progress, leaving practitioners and some women still in a dilemma. This article addresses the WHI in the context of other studies and discusses possible reasons for the unexpected results.

Fatty acid composition of serum phospholipid of premenopausal women and postmenopausal women receiving and not receiving hormone replacement therapy

OBJECTIVE

To compare the fatty acid composition of serum phospholipid of premenopausal women with that of postmenopausal women receiving and not receiving hormone replacement therapy (HRT).

DESIGN

Women between the ages of 43 and 70 were recruited for two separate case-comparison studies. Participants were grouped as either premenopausal, postmenopausal receiving HRT, or postmenopausal not receiving HRT. All participants were required to complete a 3-day dietary record before providing a 12-h fasting blood sample. Fatty acid composition of phospholipids and lipid concentrations was determined from serum samples.

RESULTS

The postmenopausal women receiving HRT had significantly higher concentrations of palmitic acid (16:0), palmitoleic acid (16:1), and di-homo-gamma-linolenic (20:3n-6) and significantly lower levels of docosapentaenoic acid (22:5n-3) than the other groups in both studies. In addition, the postmenopausal women receiving HRT had lower levels of behenic (22:0), lignoceric (24:0), and nervonic acid (24:1) in comparison with the postmenopausal women not receiving HRT.

CONCLUSION

The results of this study indicate that the fatty acid composition of serum phospholipids in women is influenced by menopausal status and hormone use. These results are of interest because high levels of 20:3n-6 and low levels of docosapentaenoic acid have been associated with increased myocardial infarction plus stroke mortality from cardiovascular disease.

The demise of HRT? The long-term safety of hormone replacement therapy

The role of hormone replacement therapy (HRT) in the health of middle-aged women has come a full circle. HRT has been widely accepted as the treatment of choice for the management of menopausal symptoms. However, the Women's Health Initiative (WHI) and other recent randomised controlled trials have failed to confirm beliefs of other potential benefits in reducing the risk of coronary artery disease (CAD) and stroke. Indeed, early increases in cardiac event and stroke rate have been seen in women taking combination HRT. An increased risk of breast cancer diagnosis has also been confirmed in HRT users. The use of HRT now needs to be regarded as a short-term therapy for menopausal symptom management with treatment individualised for each woman.

Estabilización de la placa de ateroma: un nuevo concepto basado en la biología dinámica de la aterosclerosis

As it is well-known, a thrombus evolving into a disrupted/eroded atherosclerotic plaque causes most acute coronary syndromes. Plaque stabilization via reduction of the lipid core and/or thickening of the fibrous cap is one of the possible mechanisms accounted for the clinical benefits displayed by different anti-atherosclerotic strategies. The concept of plaque stabilization was developed to explain how lipid-lowering agents could decrease adverse coronary events without substantial modifications of the atherosclerotic lesion. A number of imaging modalities (vascular ultrasound, MRI, and coronary computed tomography) are used for non-invasive assessment of atherosclerosis; most of them can identify luminal stenosis, wall thickness and plaque volume and composition, and can even characterize the rupture-prone vulnerable plaques. Several classes of drugs, including statins, ACE inhibitors, -blockers, and antithrombotics, are able to reduce the plaque burden and the incidence of cardiovascular events; this may be attibutable, at least in part, to plaque-stabilizing effects and the improvement of endothelial dysfunction.

Issues of hormone replacement therapy and cardiovascular disease for elderly women

Based on epidemiologic studies demonstrating mainly positive biologic effects of estrogen on cardiovascular risk factors and outcomes, earlier recommendations decreed that most, if not all women should be treated with long-term postmenopausal hormone replacement. A review of recent controlled clinical trials demonstrates that previously held dictums might not prove accurate. For elderly women, the decision to begin hormone replacement therapy should not be based on an assumption of protection from cardiovascular diseases. A careful assessment of the risks and benefits, as well as acknowledgement of the outcomes for which hormone replacement therapy has unknown impact, is needed for any decision to begin, continue, or stop hormone replacement therapy.