The goal of this study was to assess psychosocial functioning in older patients with bipolar I disorder compared with healthy subjects and to identify the psychopathological factors associated with poor functioning in patients.

We recruited 68 euthymic patients with bipolar I disorder from the outpatient unit and 89 healthy controls who were older than 50 years of age. In addition to clinical variables, we used other standardized measures, including the Young Mania Rating Scale, the Hamilton Depression Rating Scale, the Hamilton Anxiety Rating Scale, the Functional Assessment Short Test, and the Montreal Cognitive Assessment.

Older patients with bipolar I disorder had poorer psychosocial functioning in general and in the domains of occupation, autonomy, and cognition than the healthy controls on the basis of previously defined Functional Assessment Short Test cutoff scores. We found that 35.3% (95% CI: 23%-47%) of the patients did not have clinically significant functional impairment, 38.2% (95% CI: 26%-50%) had mild impairment, and 26.5% (95% CI: 16%-37%) had moderate impairment. Depressive symptoms and impaired cognition were associated with poor overall functioning.

The level of psychosocial functioning was heterogeneous among the patients. Subsyndromal depressive symptoms, even at low levels, and impaired cognition predicted poor functioning in euthymic middle-aged and older patients with bipolar I disorder.