Perceived health, medical, and psychiatric conditions in individual and dual-use of marijuana and nonprescription opioids.

Objective: Marijuana and nonprescription opioids remain the two most commonly used illicit substances in the United States. They have commonalities, yet the use of both at the same time may have a greater impact on psychological and health outcomes. Research is needed to determine whether dual-use is associated with more negative outcomes than individual substance use.

Method: We used the National Epidemiologic Survey of Alcohol and Related Conditions (NESARC) Wave 1 (W1; N = 43,093), Wave 2 (W2; N = 34,653), and the more recent NESARC-III (N3; N = 36,171) to compare nonuse with use of marijuana, nonprescription opioids, or both. We examined perceived health, pain interference, pain-related medical conditions, psychiatric conditions, and suicidality.

Results: Individual use and dual-use were more common in N3 than in W1. W1 dual-use and nonprescription opioid-only use predicted worse outcomes for most variables prospectively and cross-sectionally, including pain interference and poorer general health. Associations between marijuana-only use and outcomes were not as strong; however, marijuana was associated with depression and suicidal ideation.

Conclusion: Nonprescription opioid use is concerning with dual-use predicting poorer perceived health and pain interference with work 3 years later along with strong relationships to suicidality and psychiatric conditions. Marijuana and nonprescription opioid dual-use is a possible treatment target. Substance interventions may be enhanced by addressing alternative pain care; chronic conditions; and/or psychiatric comorbidity. Differences in outcomes between substance use and nonuse were smaller recently in N3, particularly for marijuana use only. This may be due to increased access decreasing differences between those using and not using these drugs. (PsycINFO Database Record (c) 2019 APA, all rights reserved).