Lower levels of bodily pain increase risk for non-medical use of prescription drugs among current US reserve soldiers

Background: Military populations have a higher prevalence of pain compared to their civilian counterparts and are also at increased risk for substance use. The link between clinically significant pain and substance use has been established, but it is unclear if lower levels of pain relate to risk. The goal of this inquiry was to determine if level of bodily pain was associated with increased risk of current substance use over time among a community sample of U.S. Army Reserve/National Guard (USAR/NG) soldiers. Methods: Data were drawn from an ongoing study of USAR/NG soldiers. We used generalized estimating equations to examine the longitudinal impact of baseline bodily pain level (modeled in standard deviations from the mean pain score) on current drug use (illicit and non-medical use of prescription drugs [NMUPD]) among soldiers (n = 387) over two-years. Final models controlled for baseline post-traumatic stress disorder (PTSD), anxiety, and depression symptomatology, history of deployment (yes/no), years of military service, and substance use norms. Results: Bodily pain was longitudinally associated with increased odds of current NMUPD (AOR: 1.49, p < .05), but not with the current use of illicit drugs (AOR: 1.18, p > .05), controlling for symptoms of PTSD, anxiety, depression, deployment, years of service, and substance use norms. Conclusions: Overall, our findings indicate that bodily pain is longitudinally associated with NMUPD among male soldiers, but not with illicit drugs. Significantly, our results stem from a non-clinical sample of soldiers with overall lower levels of pain. This indicates that pain may be important, even at lower levels, and underscores the importance of early non-pharmacologic interventions for pain.