Hormonal determinants of depression and cognitive function in independently-living elders.

OBJECTIVE To study the potential associations among circulating insulinlike growth factor 1 (IGF-1) and adrenal and gonadal steroids with cognitive status and depression in a group of independently-living elders. DESIGN Population-based cross sectional study. METHODS A total of 313 individuals (160 women and 153 men, with a mean age of 76.7±7 years) participated in this study. A physical examination, assessment of functional capacity, cognitive function, depression, educational level and measurement of plasma cortisol, dehydroepiandrosterone (DHEA) and its sulphate (DHEAs), testosterone, estradiol, and IGF-1 were performed. RESULTS In women, adrenal steroids showed a negative correlation with global cognition (β=-0.79; p=0.03 for DHEA and β=-0.27; p=0.002 for cortisol). A positive correlation with IGF-1 (β=0.026; p=0.04) was found for cognition in women after adjustment for depression. For memory function, DHEA correlated negatively but no relationship with IGF-1 and cortisol was observed. No relationships with cognition were observed in men for any of the steroids or other hormones studied. Educational level showed the highest protective effect (odds ratio [OR] = 6.25) for preserved cognition for both sexes; in women, OR for deteriorated cognition with age, DHEA and cortisol were 1.14, 1.57 and 1.09, respectively. No associations between depression and hormonal profile were found in either sex. CONCLUSIONS Educational level was positively associated with cognitive function in independently-living elderly men and women, while adrenal steroids were associated with impaired cognition in elderly women but not in men. The hormonal milieu seemed to have little or no influence on depression in the men and women studied.