Objective: Drug abuse is associated with substantial impairments in decision making. However, little is known about the time course of changes in decision-making ability after abstinence or about the effects of stress on decision making in individuals recovering from heroin dependence after different durations of abstinence.
Method: First, the authors assessed decision-making performance with the original card version of the Iowa Gambling Task in formerly heroin-dependent patients who had been abstinent for 3, 7, 15, or 30 days or 3, 6, 12, or 24 months. Second, patients who had been abstinent from heroin for 15 or 30 days or 3, 12, or 24 months were challenged with acute stress induced by the Trier Social Stress Test. Third, the β-adrenoceptor antagonist propranolol (40 mg) was administered 1 hour before stress to those who had been abstinent for 30 days or 12 or 24 months.
Results: The short-term abstinence groups (3-30 days) performed worse on the Iowa Gambling Task compared with the long-term abstinence groups (3-24 months). Psychosocial stress unmasked a latent impairment in decision making in the 24-month abstinence group, which seemed to perform identically to healthy comparison subjects in the absence of stress. Propranolol blocked the stress-induced impairment of decision making, which was seen only in the formerly heroin-dependent patients.
Conclusions: Stress can exacerbate an already existing impairment of decision making or unmask a latent one in individuals recovering from heroin dependence. The β-adrenergic blockade reduces this effect and might hold promise for treatment of substance use disorders.