Is impulsivity in remitted bipolar disorder a stable trait? A meta-analytic review

Objective: To review scores on measures of impulsivity in remitted bipolar disorder.

Data source: We used keywords "impulsivity and bipolar" and "impulsivity and mania" to narrow down our search on Medline, EMBASE and Psychinfo to include those studies that had reported impulsivity scores using validated and reliable assessment measures in remitted bipolar disorder (both I and II). We searched all English language studies from 1990 to October 2012.

Study selection: Nineteen reports met the inclusion criteria and were reviewed by two abstractors independently.

Data abstraction: We generated weighted mean differences (WMDs) from pooled data using RevManager 5.0 from Cochrane analysis.

Results: The Barratt Impulsivity Scale (BIS) 11 was the instrument most commonly used. Nineteen studies met the inclusion criteria, of which 2 were excluded due to incomplete data. A WMD of 12.8 was observed for BIS 11 total scores, 4.3 on the motor component, 4.1 on the cognitive and 7.6 on the non-planning components of the BIS 11 respectively.

Conclusion: Impulsivity is significantly higher in remitted bipolar patients than normal controls. Non-planning impulsivity is a key domain affected in bipolar disorder, which may represent a stable trait.