Cancer-Related Pain Is an Independent Predictor of In-Hospital Opioid Overdose: A Propensity-Matched Analysis.

BACKGROUND: About 50% of patients with cancer who have undergone surgery suffer from cancer-related pain (CP). The use of opioids for postoperative pain management presents the potential for overdose, especially among these patients.

OBJECTIVE: The primary objective of this study was to determine the association between CP and postoperative opioid overdose among inpatients who had undergone major elective procedures. The secondary objective was to assess the relationship between CP and inpatient mortality, total hospital charge, and length of stay in this population.

METHODS: Data of adults 18 years and older from the National Inpatient Sample (NIS) were analyzed. Variables were identified using ICD-9 codes. Propensity-matched regression models were employed in evaluating the association between CP and outcomes of interest.

RESULTS: Among 4,085,355 selected patients, 0.8% (N = 2,665) had CP, whereas 99.92% (N = 4,082,690) had no diagnosis of CP. We matched patients with CP (N = 2,665) and no CP (N = 13,325) in a 1:5 ratio. We found higher odds of opioid overdose (adjusted odds ratio [aOR] = 4.82, 95% confidence interval [CI] = 2.68-8.67, P < 0.0001) and inpatient mortality (aOR = 1.39, 95% CI = 1.11-1.74, P = 0.0043) in patients with CP vs no CP. Also, patients with CP were more likely to stay longer in the hospital (12.76 days vs 7.88 days) with higher total hospital charges ($140,220 vs $88,316).

CONCLUSIONS: CP is an independent risk factor for opioid overdose, increased length of stay, and increased total hospital charges.