The Brief Assessment of Cognition In Affective Disorders (BAC-A):performance of patients with bipolar depression and healthy controls.

BACKGROUND: Cognitive deficits in bipolar disorder are significant enough to impact everyday functioning. A key question for treatments aimed at cognition is which cognitive domains are most affected by bipolar disorder and which cognitive tests have the best psychometric characteristics for this population.
METHOD: 432 patients assessed at study entry in a treatment study of bipolar depression were assessed with a version of a new cognitive measure - the Brief Assessment of Cognition in Affective Disorder (BAC-A), which assesses traditional cognitive constructs with six subtests measuring memory, processing speed, working memory, and reasoning and problem solving, and a new measure of affective processing. From the cohort of 432 patients, 309 were selected based upon their demographic similarities to a previously collected healthy control sample of 309 subjects. Patients and controls completed the traditional cognitive tests and the Affective Processing Test. Results. Patients with bipolar depression and healthy controls differed significantly on all cognitive measures (P<0.001). The two alternate forms of the Affective Processing Test were very similar in both groups. The most robust discriminator of the groups was a composite score that combined the six core cognitive subtests of the Brief Assessment of Cognition (BAC) with two of the measures from the Affective Processing Test. LIMITATIONS: Test-retest reliabilities of the individual Affective Processing Test measures were low.
CONCLUSION: The BAC-A is sensitive to the cognitive impairments in bipolar disorder patients in traditional neuropsychological domains and in cognitive processes believed to be specifically impaired in affective disorders.