Cognitive impairment in bipolar disorder in old age: literature review and findings in manic patients.

Background: Descriptions of aged patients with bipolar (BP) disorder have commented on cognitive impairments. However, the literature regarding cognitive test performance in this population has apparently been scant.

Method: 1. We reviewed studies reporting cognitive performance in aged BP patients. 2. We compared the performance of elderly BP manic patients and aged community comparison subjects on the Mini-Mental State Examination (MMSE) and the Mattis Dementia Rating Scale (DRS).

Results: 1. Seven published studies of cognitive measures in aged BP patients were identified. They utilized different assessment methods and addressed different illness states, but they indicate impairments in these patients. 2. In our sample, the manic patients (n=70) had lower MMSE scores and DRS scores than did the comparison subjects (n=37). In these patients, cognitive scores were not significantly associated with Mania Rating Scale scores.

Limitations: The patients in our study were assessed cross-sectionally, and they were treated naturalistically.

Conclusions: Manic or depressed BP elders have impaired cognitive function; in some patients these impairments may persist. Research characterizing these impairments and their clinical implications is warranted.