Comparative Study of Delay Discounting Rates in Alcohol and Opioid Dependence in Northern India

The study of delay discounting (DD) in addictive disorders helps in understanding why an individual chooses addictive substances immediately over possible long-term gains. Individuals with addictive disorders are seen to consistently have steeper DD compared to healthy controls. The aim of this study was to compare the delay discounting rate (DDR) between individuals seeking treatment for alcohol dependence syndrome (ADS) and opioid dependence syndrome (ODS).

A total of 125 individuals (ADS: 61, ODS: 64) seeking treatment in an addiction treatment facility in North India were assessed. DDR was measured by a 27-item Monetary Choice Questionnaire (MCQ). Other assessment tools included were Addiction Severity Index-Lite (ASI), Clinical Institute Withdrawal Assessment of Alcohol Scale-Revised (CIWA-Ar), Clinical Opiate Withdrawal Scale (COWS), Mini International Neuropsychiatric Interview (MINI)-Screen, Barratt Impulsiveness Scale-11 (BIS-11), Verbal Adult Intelligence Scale (VAIS), and Likert Scale for craving. A nonparametric Mann-Whitney U test was applied as a test of significance for the quantitative characteristics, χ² for the categorical variables, and Karl Pearson's correlation coefficient for the relationship between the scores of DDR and clinical variables. The estimate of the DDR was compared with the scores obtained on the assessment tools.

The sociodemographic (except marital status) and most of the clinical characteristics (barring duration, BIS-nonplanning impulsivity (NPI), ASI scores for domains of alcohol, drug, and legal) were comparable across the ADS and ODS groups. The MCQ-based estimated score for DDR was significantly higher for the ODS group across all the DD categories (overall, small, medium, and large). A consistent significant positive correlation was noted in both groups with DD, craving, BIS, BIS-MI, BIS-AI, BIS-NPI, and ASI-Medical (except with DD-small), and negative with VAIS.

Patients with ODS discount future rewards more steeply than patients with ADS. Nonplanning impulsivity possibly affects the way in which individuals with ODS make decisions.