BACKGROUND: Loneliness is highly prevalent among older people, has serious health consequences and is an important predictor of mortality. Loneliness and depression may unfavourably interact with each other over time but data on this topic are scarce.
AIMS: To determine whether loneliness is associated with excess mortality after 19 years of follow-up and whether the joint effect with depression confers further excess mortality.
METHOD: Different aspects of loneliness were measured with the De Jong Gierveld scale and depression with the Centre for Epidemiologic Studies Depression Scale in a cohort of 2878 people aged 55-85 with 19 years of follow-up. Excess mortality hypotheses were tested with Kaplan-Meier and Cox proportional hazard analyses controlling for potential confounders.
RESULTS: At follow-up loneliness and depression were associated with excess mortality in older men and women in bivariate analysis but not in multivariate analysis. In multivariate analysis, severe depression was associated with excess mortality in men who were lonely but not in women.
CONCLUSIONS: Loneliness and depression are important predictors of early death in older adults. Severe depression has a strong association with excess mortality in older men who were lonely, indicating a lethal combination in this group.