Cortisol secretion and functional disabilities in old age: importance of using adaptive control strategies.

OBJECTIVES To examine whether the use of health-related control strategies moderates the association between elevated diurnal cortisol secretion and increases in older adults' functional disabilities. METHODS Functional disabilities of 164 older adults were assessed over 4 years by measuring participants' problems with performing activities of daily living. The main predictors included baseline levels of diurnal cortisol secretion and control strategies used to manage physical health threats. RESULTS A large increase in functional disabilities was observed among participants who secreted elevated baseline levels of cortisol and did not use health-related control strategies. By contrast, high cortisol level was not associated with increases in functional disabilities among participants who reported using these control strategies. Among participants with low cortisol level, there was a relatively smaller increase in functional disabilities over time, and the use of control strategies was not significantly associated with changes in functional disabilities. CONCLUSIONS The findings suggest that high cortisol level is associated with an increase in older adults' functional disabilities, but only if older adults do not engage in adaptive control strategies.