Association of cardiovascular risk factors and disease with depression in later life

The objective of this study is to determine the association between established cardiovascular risk factors and depression among older men.

The authors conducted a cross-sectional study of a community-representative sample of 5,439 men aged 71-89 years. Cardiovascular disease and risk factors assessed included history of diabetes, hypertension, angina, myocardial infarction, and stroke; current smoking; total cholesterol and fractions; triglycerides; total plasma homocysteine; and MTHFR677 genotype. Depression was defined by a Geriatric Depression Scale 15 items score of 7 or greater.

A complete data set was available for 4,204 men, of whom 212 were depressed (5%). Men who were depressed reported higher frequency of diabetes (23.1% versus 13.2%), angina (30.2% versus 20.4%), myocardial infarction (26.2% versus 16.0%), and stroke (23.6% versus 9.1%) than nondepressed men. Participants with depression were also more likely to have plasma homocysteine above 15 mumol/L (39.1% versus 25.5%) and high triglycerides (32.1% versus 20.9%) than nondepressed subjects. Depressed older men were also more likely to be active smokers (9.9% versus 4.8%). The other factors measured in the study were not significantly associated with depression. Estimation of the population-attributable fraction (PAF) after logistic regression showed that high plasma homocysteine had the highest PAF for depression (PAF:15%, 95% confidence interval [95% CI]: 5%-23%) followed by high triglycerides (PAF: 11%, 95% CI: 2%-18%), angina (PAF: 9%, 95% CI: 2%-15%), stroke (PAF: 8%, 95% CI: 3%-13%), diabetes (PAF: 7%, 95% CI: 1%-13%), myocardial infarction (PAF: 5%, 95% CI: 0%-11%), and smoking (PAF: 5%, 95% CI: 1%-9%).

High plasma homocysteine and triglycerides appear to account for a considerable proportion of cases of depression in older men. The successful management of these risk factors may contribute to decrease the prevalence of depression in later life.