Cerebrovascular risk factors, executive dysfunction, and depression in older primary care patients

Objective: "Executive" cognitive functions may be of particular clinical importance in geriatric depression and may reflect underlying cerebrovascular disease. This study examined the associations of selected components of executive function with cerebrovascular risk factors, depression, and overall functional status. Method: Study measures were completed on 448 primary care patients aged >= 65 years based on patient interviews and medical chart review. Multiple regression techniques determined the presence of specified independent associations. Results: Some but not all study hypotheses were confirmed. Cerebrovascular risk factors were associated with major depression and with some cognitive measures, but their associations with depression and with the most specific measures of executive function were limited and not independent of overall medical burden. Measures of initiation-perseveration and mental set shifting were associated with overall functional disability; these cognitive measures were not associated with depression diagnosis, or with depressive symptoms when also covarying medical burden or excluding patients with dementia. Conclusions: Clinicians should be aware of the potential functional significance of these components of cognition. Longitudinal risk factor studies and complementary techniques such as neuroimaging may help identify pathogenetically distinct subgroups of later-life depression that might respond preferentially to specific interventions.