To evaluate the association between traumatic brain injury
(TBI) and nonfatal opioid overdose
, and the role of psychiatric conditions as mediators of this association.
receiving care at national Department of Veterans
Affairs (VA) facilities from 2007 to 2012.
In total, 49 014 veterans
aged 18 to 40 years receiving long-term opioid treatment of chronic noncancer pain.
Longitudinal cohort study using VA registry data.
TBI was defined as a confirmed diagnosis (28%) according to VA comprehensive TBI evaluation; no TBI was defined as a negative primary VA TBI screen (ie, no head injury). Nonfatal opioid overdose
was defined using ICD-9
(International Classification of Diseases, Ninth Revision
) codes. We performed demographic-adjusted Cox proportional hazards regression. We quantified the impact of co-occurring and individual psychiatric conditions (mood, anxiety, substance use, and posttraumatic stress disorder) on this association using mediation analyses.
with TBI had more than a 3-fold increased risk of opioid overdose
compared with those without (adjusted hazards ratio [aHR] = 3.22; 95% confidence interval [CI], 2.13-4.89). This association was attenuated in mediation analyses of any co-occurring psychiatric condition (aHR = 1.77; 95% CI, 1.25-2.52) and individual conditions (aHR range, 1.52-2.95).
TBI status, especially in the context of comorbid conditions, should be considered in clinical decisions regarding long-term use of opioids in patients with chronic pain