Bipolar disorder in older adults: a critical review

Objectives: The goal of this article is to provide a comprehensive critical review of studies reporting the prevalence, features, age of onset, course, comorbidity, and neuropsychology of, as well as service utilization, in bipolar disorder in older age. Methods: We searched the Medline, Pubmed, and PsycINFO databases using combinations of the keywords 'Bipolar', 'Manic/a', 'Manic Depression', 'Elderly', and 'Older'. We included English-language reports presenting quantitative data on the prevalence and/or any descriptive information about adults with bipolar disorder over age 50. Findings from similar studies were pooled when possible. A total of 61 studies met our broad criteria. Results: Common methodological problems in the published studies included small sample sizes, retrospective chart review, lack of standardized measures, overemphasis on inpatients, and dearth of longitudinal data. Strong evidence indicates that bipolar disorder becomes less common with age, accounts for 8-10% of late life psychiatric admissions, is associated with neurologic factors in late-onset groups, and is a heterogeneous life-long illness. Weak or inconsistent evidence was found for a higher prevalence of mixed episodes in older adults, a lower treatment response, and the association with lower family history in late-onset groups. Minimal information is available on bipolar depression in late life. Conclusions: Bipolar disorder in old age is a growing public health problem. Greater research on bipolar disorder in older people will assist in enhancing services to this group as well as inform research on bipolar disorder across the life span.