Psychiatric diagnoses and personality traits associated with disadvantageous decision-making

Decision-making impairment is an important feature of psychiatric disorders. In a large comorbid psychiatric population, we explored the link between decision-making deficit and clinical variables.

We used the Iowa Gambling Task to measure decision-making in 317 patients. Psychiatric diagnoses were made according to the DSM-IV criteria. Self-questionnaires were used to assess several personality traits. The last and most severe suicidal acts were characterized.

(1) After controlling for age and medication intake, a past history of suicide attempt (OR=2.0 [1.1-3.8]) and normothymic bipolar disorders (OR=3.4 [1.1-10.5]) were significantly and independently associated with impaired decision-making. (2) Decision-making performance was significantly correlated with affective lability. (3) No association was found between decision-making skills and suicidal characteristics.

A lack of statistical power may have masked associations with obsessive-compulsive disorder and anorexia nervosa. We did not control for other cognitive functions except attention.

This study supports the independent association of decision-making impairment with vulnerability to suicidal behaviour but not with substance abuse. Normothymic bipolar disorders, but not unipolar disorders, were also linked to low performance. At the dimensional level, impulsivity and decision-making abilities may be distinct processes. Affective regulation skills appear to be a major influence on decision-making performance and following a relevant therapeutic target.