Attention impairment in bipolar disorder: a systematic review

Abstract

Objective: Bipolar disorder (BD) has been associated with marked cognitive impairment, including euthymic periods. Attention is among the most compromised functions in BD. Changes related to learning, memory, and visuospatial abilities can be derived from these attention impairments. The objective of this article is to review the scientific literature on the performance of BD patients in attention tests. A systematic review was performed of controlled studies that assessed attention in patients diagnosed with BD aged between 18 and 65 years. The databases included Medline, LILACS, Cochrane Library, Institute for Scientific Information Web of Knowledge, and Scientific Electronic Library Online (SciELO), and the search encompassed the period from 2008 to 2013. Only studies that had a minimum sample of 10 patients were included. A total of 110 articles fulfilled the inclusion criteria. Compared with healthy control subjects, bipolar patients showed poorer attention performance. Compared with other mental disorders, BD was associated with poorer performance than unipolar depression but better performance than schizophrenia. When bipolar patients in different phases of the disease were compared with one another, the performance of euthymic patients was similar to or better than patients in a depressive state; moreover, manic patients performed worse than depressive patients. Attention is significantly impaired in BD. Attention impairment in BD is milder than in schizophrenia but greater than in unipolar depression. Attention impairment is possibly more severe in manic and depressed episodes than in euthymic periods.