Chronic Pain and Opioid Use Disorder Increase Suicide Risk

Chronic pain and opioid use can triple suicide risk, according to a study published in Pain Medicine. Researchers say suicide risk is 3-times higher among patients with chronic non-cancer pain (CNCP) and comorbid opioid use disorder (OUD) than those without OUD.

Both individuals with chronic pain and those with substance use disorders are at increased risk for suicide.

This cross-sectional study was designed to evaluate the extent of suicide risk at the cross section of chronic pain and opioid use disorder. Patients (n=175) with non-cancer related chronic pain and opioid use disorder after receiving long-term opioid therapy (LTOT) and a group of controls (n=434) who had CNCP and received LTOT but had no evidence of opioid use were recruited at sites in 3 states in the United States between 2012 and 2018.

The 2 chronic pain cohorts were evaluated by the Coping Strategies Questionnaire (CSQ), Pain Self Perception Scale (PSPS), Patient Health Questionnaire-4 (PHQ-4), and Suicide Behavior Questionnaire-Revised (SBQ-R) instruments. High risk for suicide was defined as an SBQ-R score of 8 or greater.

The patients who had scores of low (n=499) and high (n=110) risk for suicide were aged mean 39.3 (SD, 11.7) and 34.5 (SD, 10.9) years (P <.001), 60.1% and 62.7% were women, 43.7% and 60.9% were not married (P =.002), 22.8% and 41.8% had financial difficulties (P <.001), and 23.6% and 51.8% had non-cancer related chronic pain and opioid use disorder (P <.001), respectively.

The group at high risk for suicide also had higher CSQ pain catastrophizing scores (mean, 20.9 vs 13.3; P <.001) and PHQ-4 scores (mean, 8.2 vs 4.8; P =.018) and lower subjective social support scores (mean, 15.5 vs 17.8; P <.001), social interaction scores (mean, 4.5 vs 5.2; P =.008), and instrumental social support scores (mean, 7.6 vs 8.3; P =.018) compared with the cohort not at high risk for suicide, respectively. In addition, more with high suicide risk fit the criteria for depression (21.8%) than those not at high risk for suicide (5.8%; P <.001).

Risk for suicide was associated with non-cancer related chronic pain and opioid use disorder (adjusted odds ratio [aOR], 2.40; 95% CI, 1.36-4.29; P =.003), depression (aOR, 2.04; 95% CI, 1.01-4.12; P =.047), pain catastrophizing (aOR, 1.06; 95% CI, 1.01-1.10; P =.013), and PSPS score (aOR, 1.02; 95% CI, 1.01-1.03; P <.001).

In the receiver operating characteristic curve (ROC) analyses, a PSPS cutoff score of 40 (area under the curve [AUC], 77.3%; sensitivity, 69%; specificity, 70%) and a CSQ pain catastrophizing score of 16 (AUC, 75.9%; sensitivity, 78%; specificity, 63%) best predicted high suicide risk.

These data indicated that non-cancerous chronic pain and opioid use disorder may be a risk factor for suicide.

“[C]onsistent with previous reports, several psychosocial factors, such as mental defeat, pain catastrophizing, and depression were associated with elevated risk of suicide scores in individuals with CNCP and co-morbid OUD in this patient population,” the investigators report.

This study may have been limited by relying on SBQ-R-defined suicide risk.