Introduction

Lower grip strength and measures of physical functioning are associated with all-cause mortality. Relationships among long-term weight loss, physical functioning, and mortality in older women are understudied.

Methods

Participants were 5039 women who were part of the Long Life Study (LLS) ancillary study to the Woman's Health Initiative (WHI). Average age was 78.76 ± 6.92. We defined long-term weight loss or gain as a decrease or increase of 5% or more of baseline body weight. Our primary outcome was all-cause mortality and our secondary outcomes were vascular death, and coronary heart disease (CHD). The mean follow-up time was 5.4 years. Cox regression modeling was performed for each outcome of interest. Variables of interest were weight change, grip strength, and functional status as measured by the Short Physical Performance Battery (SPPB) controlling for multiple potential confounders.

Results

Weight loss of 5% or more percent body weight was associated with a hazard ratio of 1.66 (1.37-2.01) for all-cause mortality. Weight gain was not related to mortality or cardiovascular outcomes. Those in the highest grip strength quartile had a hazard ratio of 0.51 (0.39-0.66) for all-cause mortality. For the SPPB the hazard ratio was 0.29 (0.21-0.40), adjusting for changes in weight, race, smoking, history CHD, smoking, and diabetes. Higher grip strength and SPPB were associated with lower risks for vascular death, and CHD, independently of weight change.

Conclusions

Weight loss was associated with increased mortality. Stronger grip strength and higher SPPB scores were associated with lower mortality risk independent of weight change.

Background

Prolonged sitting and physical inactivity are associated with higher circulating levels of estrogens. It is unknown whether these risk factors are associated with circulating androgens/androgen metabolites, another set of hormones implicated in the etiology of cancers in postmenopausal women.

Methods

We conducted a cross-sectional analysis of 1,782 postmenopausal women in the Women's Health Initiative Observational Study. Serum concentrations of 12 androgens/androgen metabolites were quantified using liquid chromatography-tandem mass spectrometry. Physical activity and sitting time were self-reported at baseline. We performed linear regression to estimate geometric means (GM) of androgen/androgen metabolite concentrations (pmol/L) according to physical activity and sitting time, adjusting for potential confounders and stratified by menopausal hormone therapy (MHT) use.

Results

Physical activity (≥15 vs. 0 MET-h/wk) was inversely associated with estrogen-to-androgen ratios among never/former MHT users (adj-GM = 37.5 vs. 49.6 unconjugated estrone:androstenedione; 20.2 vs. 30.3 unconjugated estradiol:testosterone; all P _trend ≤ 0.03) but was not associated among current MHT users. Prolonged sitting (≥10 vs. ≤5 h/d) was positively associated with these ratios among both never/former (adj-GM = 44.2 vs. 38.3, P _trend = 0.10; adj-GM = 23.4 vs. 20.2, P _trend = 0.17; respectively) and current MHT users (adj-GM = 197 vs. 147; 105 vs. 75.5; respectively; all P _trend ≤0.02), but the associations were statistically significant among current MHT users only. The associations persisted after adjustment for BMI. After adjustment for adrenal androgens, physical activity and sitting were not associated with androgen metabolites.

Conclusions

Physical activity and sitting were associated with serum estrogen-to-androgen ratios but not androgen metabolites.

Impact

This study contributes to our understanding of the link between physical activity, sitting, and cancer risk in postmenopausal women.