Blood pressure risk factors in healthy postmenopausal women: Physical activity and hormone replacement

The prevalence of cardiovascular disease (CVD) increases with advancing age in women, particularly after menopause. CVD risk is lower in physically active women relative to their sedentary peers, but the responsible mechanisms are not well understood. The aims of this study were to test the hypotheses that 1) physically active postmenopausal women demonstrate more favorable blood pressure (BP)-related risk factors for CVD than do sedentary healthy women and 2) women on hormone replacement therapy (HRT) also have more favorable levels of these CVD risk factors. BP-related CVD risk factors were measured in physically active women (n = 18; age 55 +/- 1 yr; n = 8 on HRT) and in healthy less-active controls (n = 34; age 59 +/- 1 yr; n = 17 on HRT). Maximal oxygen consumption was higher in the active group: whereas waist-to-hip ratio and waist circumference were lower (all P < 0.005). The active women demonstrated marginally lower (5-8 mmHg; P less than or equal to 0.10) levels of casual, 24-h, and daytime systolic BP (SEP). They also tended to have lower (P = 0.11) daytime SEP loads (percentage of BP recordings > 140/90 mmHg) and lower daytime and nighttime BP variabilities (P = 0.04) and a reduced (P < 0.007) SEP response to submaximal exercise. Women on HRT tended to have lower (3-4 mmHg; P = 0.07) levels of 24-h and nighttime diastolic BP (DBP) relative to the nonusers and smaller (P < 0.04) daytime and 24-h DBP loads. Stepwise multiple regression indicated that waist circumference was the primary predictor of most of the SEP-related CVD risk factors while HRT use was the best predictor for DBP loads. These findings indicate that, in general, physically active postmenopausal women demonstrate more favorable SBP-related CVD risk factors relative to their less-active healthy peers, which may be mediated, in part, by their lower levels of abdominal adiposity. In addition, HRT use tends to be associated with lower levels of DBP-related CVD risk factors.