Opioid dose and risk of suicide

Chronic pain is associated with increased risk of suicide, and opioids are commonly used to treat moderate to severe pain. However, the association between opioid dose and suicide mortality has not been examined closely. This retrospective data analysis described the risk of suicide associated with differing prescribed opioid doses. Data were from Veterans Affairs health care system treatment records and the National Death Index. Records analyzed were those of Veterans Affairs patients with chronic pain receiving opioids in fiscal years 2004 to 2005 (N = 123,946). Primary predictors were maximum prescribed morphine-equivalent daily opioid dose and opioid fill type. The main outcome measured was suicide death, by any mechanism, and intentional overdose death during 2004 to 2009. Controlling for demographic and clinical characteristics, higher prescribed opioid doses were associated with elevated suicide risk. Compared with those receiving ≤20 milligrams/day (mg/d), hazard ratios were 1.48 (95% confidence intervals [CI], 1.25-1.75) for 20 to <50 mg/d, 1.69 (95% CI, 1.33-2.14) for 50 to <100 mg/d, and 2.15 (95% CI, 1.64-2.81) for 100+ mg/d. The magnitude of association between opioid dose and suicide by intentional overdose was not substantially different from that observed for the overall measure of suicide mortality. Risk of suicide mortality was greater among individuals receiving higher doses of opioids, and treatment providers may want to view high opioid dose as a marker of elevated risk for suicide. Additional research is needed on opioid use, pain treatment, and suicide.