Physical activity in the year before the interview was coded as: 1) sedentary, completely inactive or light-intensity activity less than 1 h/wk; 2) light physical activity, light-intensity activity 2–4 h/wk; and 3) moderate to high physical activity, light activity at least 5 h/wk or more or moderate activity at least 1–2 h/wk.
Most of those studies specifically targeted estrogens (5–10).
We recently showed that higher E2 levels are associated with higher risk of all-cause mortality in late postmenopausal women independent of testosterone, supporting the timing hypothesis of hormone replacement therapy (HRT) in women (11, 12).
Blood samples were obtained from participants after a 12-h fast and after a 15-min rest.
Aliquots of serum were stored at −80 C and were not thawed until analyzed.
Dehydroepiandrosterone sulfate (DHEAS) was assayed using RIA commercial kits (Diagnostic Systems Laboratories).
For DHEAS, the minimum detection limit was 1.7 μg/dl; intraassay CVs for three different concentrations (low, medium, high) ranged between 4.1 and 5.3%, and interassay CVs ranged between 4.6 and 7.0%.
Women selected for this study had complete data on SHBG, total testosterone, total E2, IL-6, soluble IL-6 receptor (s IL-6r), TNF-α, and C-reactive protein (CRP).
After exclusion of 43 women who were using oral HRT (n = 33) or had been recently hospitalized (n = 10), 513 women from the original subset of 556 participants 65 yr and older were used in this analysis.
For TNF-α, intraassay CVs ranged from 1.4 to 7.9%, whereas the interassay CV was less than 21%; for s IL-6r, intraassay and interassay CVs were less than 6.0% and less than 10.0%, respectively.