Impulsivity: differential relationship to depression and mania in bipolar disorder.
BACKGROUND
Impulsivity, a component of the initiation of action, may have a central role in the clinical biology of affective disorders. Impulsivity appears clearly to be related to mania. Despite its relationship to suicidal behavior, relationships between impulsivity and depression have been studied less than those with mania. Impulsivity is a complex construct, and it may be related differently to depression and to mania.


METHODS
In subjects with bipolar disorder, we investigated impulsivity in relationship to affective symptoms. Trait-like impulsivity was assessed with the Barratt Impulsiveness Scale (BIS-11). Affective symptoms were measured using the Change version of the Schedule for Affective Disorders and Schizophrenia (SADS-C). Measures were compared using analysis of variance, multiple regression and factor analysis.


RESULTS
Impulsivity, as measured by the BIS, was related differentially to measures of depression and mania. Total and attentional impulsivity correlated independently with depression and mania scores. Motor impulsivity correlated with mania scores, while nonplanning impulsivity correlated with depression scores. These relationships were strongest in subjects who had never met criteria for a substance use disorder. Among manic symptoms, visible hyperactivity correlated most strongly with BIS scores, regardless of clinical state. Among depressive symptoms, hopelessness, anhedonia, and suicidality correlated most strongly with BIS scores.


CONCLUSIONS
Depression and mania are differentially related to impulsivity. Impulsivity is related more strongly to measures of activity or motivation than to depressive or manic affect. The relationship between impulsivity and hopelessness may be an important factor in risk for suicide.
Swann
Alan C
AC
Department of Psychiatry and Behavioral Sciences University of Texas Health Science Center Houston, Texas 77030, USA. Alan.C.Swann@uth.tmc.edu
Steinberg
Joel L
JL
Lijffijt
Marijn
M
Moeller
F Gerard
FG
D000342:Affective Symptoms / Q000175:diagnosis / Q000453:epidemiology / Q000523:psychology; D001288:Attention / Q000502:physiology; D001714:Bipolar Disorder / Q000175:diagnosis* / Q000453:epidemiology / Q000523:psychology; D003071:Cognition / Q000502:physiology; D015897:Comorbidity; D003430:Cross-Sectional Studies; D003866:Depressive Disorder / Q000175:diagnosis* / Q000453:epidemiology / Q000523:psychology; D017831:Diagnosis, Dual (Psychiatry); D039721:Diagnostic and Statistical Manual of Mental Disorders; D006801:Humans; D007175:Impulsive Behavior / Q000175:diagnosis* / Q000453:epidemiology / Q000523:psychology; D008960:Models, Psychological; D009042:Motivation; D009043:Motor Activity / Q000502:physiology; D011569:Psychiatric Status Rating Scales / Q000706:statistics & numerical data; D012044:Regression Analysis; D012307:Risk Factors; D019966:Substance-Related Disorders / Q000175:diagnosis / Q000453:epidemiology / Q000523:psychology; D013405:Suicide / Q000523:psychology