Risk of dementia and death in community-dwelling older men with bipolar disorder

Résumé

BACKGROUND: Bipolar disorder has been associated with cognitive decline, but confirmatory evidence from a community-derived sample of older people is lacking. AIMS: To investigate the 13-year risk of dementia and death in older adults with bipolar disorder. METHOD: Cohort study of 37 768 men aged 65-85 years. Dementia (primary) and death (secondary), as recorded by electronic record linkage, were the outcomes of interest. RESULTS: Bipolar disorder was associated with increased adjusted hazard ratio (HR) of dementia (HR = 2.30, 95% CI 1.80-2.94). The risk of dementia was greatest among those with textless5 years of history of bipolar disorder or who had had illness onset after 70 years of age. Bipolar disorder was also associated with increased mortality (HR = 1.51, 95% CI 1.28-1.77). Competing risk regression showed that bipolar disorder was associated with increased hazard of death by suicide, accidents, pneumonia or influenza, and diseases of the liver and digestive system. CONCLUSIONS: Bipolar disorder in later life is associated with increased risk of dementia and premature death.