Generalized atherosclerosis, cognitive decline, and depressive symptoms in old age

Background: Atherosclerosis may be linked to cognitive decline and depression in old age. Methods: The Leiden 85-Plus Study is a prospective population-based study of 599 subjects from age 85 onward. The generalized atherosclerotic burden was rated by the number of cardiovascular pathologies at baseline, as assessed by history taking from treating physicians and EKG. Cardiovascular pathologies included myocardial infarction, angina pectoris or myocardial ischemia, claudicatio intermittens, and arterial surgery. Global cognitive function (Mini-Mental State Examination), attention (Stroop Test), processing speed (Letter Digit Coding Test), immediate recall memory (Word Learning Test Immediate Recall), delayed recall memory ( Word Learning Test-Delayed Recall), and depressive symptoms (15-item Geriatric Depression Scale) were assessed each year from ages 85 through 90. The prospective associations between both the generalized atherosclerosis rating and stroke with cognitive function and depressive symptoms were analyzed by linear mixed models adjusted for sex and level of education. Results: During follow-up, there was a significant cognitive decline and a significant increase of depressive symptoms. At baseline, a history of stroke was correlated with lower global cognitive function, slower processing speed, impaired immediate and delayed recall memory, and more depressive symptoms. In addition, a higher generalized atherosclerosis rating was correlated with impaired global cognitive function, lower attention, and a slower processing speed at baseline. During follow-up, a higher generalized atherosclerosis rating was associated with an accelerated decline of immediate recall memory and delayed recall memory. In contrast, there was no relation between the generalized atherosclerosis rating and depressive symptoms, either in the cross-sectional analysis or in the prospective analysis. Conclusion: In the population at large, generalized atherosclerosis contributes to cognitive decline in old age but not to depression.