Predictors of worsening insulin sensitivity in postmenopausal women

Objective The purpose of this study was to determine predictors of worsening insulin sensitivity in postmenopausal women. Study design Seventy-one nonobese postmenopausal women were assigned randomly to receive hormone replacement therapy (conjugated estrogens, 0.625 mg, plus medroxyprogesterone acetate, 2.5 mg) or placebo daily for 1 year (34 women received hormone replacement therapy, and 37 women received placebo). At baseline and 12 months, the women received a computed tomography scan at the L4-L5 vertebral disk space, a dual x-ray absorptiometry scan, a euglycemic hyperinsulinemic clamp to measure insulin sensitivity, and a lipid profile. Declining insulin sensitivity was defined as the largest quartile change in insulin sensitivity in the women who received the placebo (–1.42 mg/min/kg lean body mass). Results By univariate analysis, we found that significant predictors of worsening insulin sensitivity were the use of hormone replacement therapy, baseline insulin sensitivity, a younger age, and <10 years since menopause. By logistic regression, we determined that hormone replacement therapy use and higher baseline insulin sensitivity were independent predictors of worsening insulin sensitivity. Conclusion The use of hormone replacement therapy and baseline insulin sensitivity are significant independent predictors of the development of worsening insulin sensitivity in postmenopausal women.