Background: Depression in old age is associated with an increased mortality risk of cardiovascular disease but the mortality risk from non-cardiovascular causes is disputed.
Objective: To investigate the effect of depression on cardiovascular and non-cardiovascular mortality in old age.
Methods: We prospectively followed 500 subjects from age 85 years onwards within the population-based Leiden 85-plus Study. Depressive symptoms were assessed annually with the 15-item Geriatric Depression Scale (GDS-15). Mortality risks were estimated in a Cox proportional-hazards model with the annual assessment of depression (GDS-15> or =4 points) as a time-dependent covariate.
Results: During 1654 person-years of follow-up (mean per person, 3.2 years), depression was associated with a two-fold increase of all cause mortality [Relative Risk (RR), 1.83; 95% Confidence Interval (CI), 1.24-2.69] that was not explained by comorbid conditions. Both cardiovascular mortality and non-cardiovascular mortality contributed equally to the excess mortality (RR 1.95 and 1.75 respectively).
Conclusion: Depression in old age contributes to an increase of both cardiovascular and non-cardiovascular mortality. Motivational depletion may play an important role in the increased mortality in elderly with depression.