Cardiovascular disease and death associated with depression and antidepressants in the Melbourne Longitudinal Studies on Healthy Ageing (MELSHA).

BACKGROUND: Cardiovascular disease (CVD) and death may be associated with depression and antidepressants, but published findings remain equivocal. The authors aimed to determine the risk of CVD incidence and death associated with several classifications of depression.
METHODS: A prospective cohort study was conducted (1994-2006) in a regionally representative sample of 1000 non-institutionalised older Australians age 65+ years (47% men). Endpoints were non-fatal CVD incidence and death over 10 and 12-years, respectively. Depression incidence was assessed at 2-years. Depression related predictors were defined by symptoms (Psychogeriatric Assessment Scales, depression scale) and/or antidepressants to determine independent and/or joint effects on endpoints. Cox regressions determined unadjusted and multiple-adjusted (for significant covariates) hazard ratios (HR).
RESULTS: Baseline response rate was 70.3%. Aggregate dropout rate was approximately 24% for survivors at biennial follow-ups, but death status was ascertained for all participants. Several classifications of depression predicted death in unadjusted analyses (39-60% >1), but effects disappeared in multiple-adjusted analyses (in which all HRs became <1 and non-significant). Depression related predictors were thus not associated with CVD incidence; or death after accounting for confounding mostly by CVD, diabetes and poor functional health covariates. Prevalent arthritis, respiratory disease and daily pain were predictors (P < 0.05) of depression incidence.
CONCLUSIONS: Depression related predictors were not independently associated with CVD incidence or death in older people. Antidepressants were not associated with CVD or premature death, accounting for whether participants' remained symptomatic or not. Depression co-occurs with and might be partly caused by chronic disease and poor functional health.