Non-medical use of prescription opioids represents a national public health concern of growing importance. Mood and anxiety disorders are highly associated with non-medical prescription opioid use. The authors examined longitudinal associations between non-medical prescription opioid use and opioid disorder due to non-medical opioid use and mood/anxiety disorders in a national sample, examining evidence for precipitation, self-medication and general shared vulnerability as pathways between disorders.

Data were drawn from face-to-face surveys of 34 653 adult participants in waves 1 and 2 of the National Epidemiologic Survey on Alcohol and Related Conditions. Logistic regression models explored the temporal sequence and evidence for the hypothesized pathways.

Baseline lifetime non-medical prescription opioid use was associated with incidence of any mood disorder, major depressive disorder (MDD), bipolar disorder, any anxiety disorder and generalized anxiety disorder (GAD in wave 2, adjusted for baseline demographics, other substance use, and co-morbid mood/anxiety disorders). Lifetime opioid disorder was not associated with any incident mood/anxiety disorders. All baseline lifetime mood disorders and GAD were associated with incident non-medical prescription opioid use at follow-up, adjusted for demographics, co-morbid mood/anxiety disorders, and other substance use. Baseline lifetime mood disorders, MDD, dysthymia and panic disorder were associated with incident opioid disorder due to non-medical prescription opioid use at follow-up, adjusted for the same covariates.

These results suggest that precipitation, self-medication as well as shared vulnerability are all viable pathways between non-medical prescription opioid use and opioid disorder due to non-medical opioid use and mood/anxiety disorders.