Correlates of hypersecretion of cortisol in the normal elderly population : investigating subjective complaints of memory and depressive symptomatology

Knowing the detrimental effects that chronic hypersecretion of cortisol can have on hippocampal-dependent memory and the anatomical integrity of the hippocampus in normal elderly humans and animals, the goal of this project was to describe correlates of cortisol hypersecretion in normal elderly humans. Subjective complaints of memory and depressive symptomatology were chosen as possible correlates because they have previously been linked to cortisol hypersecretion. Normal elderly volunteers were recruited based on their subjective complaints of memory and/or depression and grouped as a LOW, MODERATE or HIGH cortisol secretor, based on salivary cortisol levels measured over the course of one year. Subjects were administered neuropsychological tests and psychosocial and environmental questionnaires that have been known to differ with different stress profiles. Results revealed that subjective complaints of memory and depressive symptomatology were not significantly related to hypersecretion of cortisol. Diurnal and seasonal cortisol secretory patterns did, however, differentiate HIGH secretors from MODERATE and LOW secretors such that there was a loss of diurnal and seasonal rhythmicity in the HIGH secretor group. Additionally, psychosocial questionnaires focusing on locus of control revealed that LOW secretors externalized control mechanisms more than MODERATE secretors. The possibility of lack of cortisol rhythmicity as a correlate of chronic hypersecretion of cortisol in young-elderly individuals as well as changes in locus of control mechanisms during aging are discussed