Abstract
BACKGROUND: Cardiovascular diseases have been associated with depression in later life, and a potential mechanism is inhibition of angiogenesis. We designed this study to determine if depression is associated with higher serum concentration of endostatin, an endogenous angiogenesis inhibitor. METHODS: We performed a cross-sectional examination of a random sample of men aged 69-86 years. Those who scored 7 or higher on the 15-item Geriatric Depression Scale were deemed depressed. We determined the concentration of serum endostatin using a reproducible assay. Other measures included age, education, body mass index, smoking, history of depression, use of antidepressants, hypertension, diabetes, coronary heart disease and stroke, high sensitivity C-reactive protein, plasma homocysteine, triglycerides and cholesterol. We used logistic regression to investigate the association between endostatin and depression, and adjusted the analyses for confounding factors. RESULTS: Our sample included 1109 men. Sixty-three (5.7%) men were depressed. Their serum endostatin was higher than that of nondepressed participants (p = 0.021). Men in the highest decile of endostatin had greater adjusted odds of depression (odds ratio [OR] 1.78, 95% confidence interval [CI] 1.03-3.06). A doubling of endostatin doubled the odds of depression (OR 1.93, 95% CI 1.31-2.84). The probability of depression increased with the concentration of endostatin in a log-linear fashion up to a maximum of about 20%-25%. LIMITATIONS: The cross-sectional design limits the study's ability to ascribe causality to the association between high endostatin and depression. CONCLUSION: Serum endostatin is associated with depression in older men. It remains to be established whether correction of this imbalance is feasible and could decrease the prevalence of depression in later life.