Delay-discounting among homeless, out-of-treatment, substance-dependent men who have sex with men

Abstract

Background: Impulsivity is associated with substance use; however, to date, impulsivity has not been characterized among a sample of homeless, non-treatment seeking, substance-dependent men who have sex with men (MSM). Objectives: The aim of this study was to utilize the delay-discounting instrument to assess impulsive behaviors among a subsample of homeless, non-treatment seeking, substance-dependent men who have sex with men (S-D MSM) enrolled in a randomized, controlled, contingency management (CM) trial. Methods: Twenty S-D MSM participants from the CM parent study were matched on age and ethnicity to 20 non-substance-dependent, non-homeless control participants using propensity scores (N = 40) and were administered the delay-discounting procedure. Results: Although discounting values decreased rapidly with time in both groups, the S-D MSM participants consistently discounted rewards more steeply than controls (p = .05), particularly at all intermediate measured timeframes. The S-D MSM participants also presented greater median discounting rates (k values) compared with the control group (m_{S-D MSM} = 2.39 (SD = 3.72) vs. m_ctrl = 1.27 (SD = 3.71), p ≤ .01). Conclusion: This work extends existing findings of increased delay-discounting among substance-dependent individuals to homeless, substance-dependent, non-treatment seeking MSM. Scientific Significance: A better understanding of the prevalence of delay-discounting type behaviors among homeless, substance-dependent MSM can be used to inform the development of tailored substance abuse interventions for this high-risk population.

• delay-discounting
• substance-dependent
• MSM

Acknowledgments

Funding for this study was provided by NIDA Grants R01 DA015990 and NOT-DA-04-002, and the County of Los Angeles Department of Public Health, Office of AIDS Programs and Policy Contract H-700861.

Declaration of Interest

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this paper.