Efficacy of prophylactic laxatives against opioid-induced constipation: retrospective propensity score matching analysis

Purpose: Opioid-induced constipation (OIC) is problematic for patients with cancer receiving opioid therapy. Some guidelines recommend initiating regular laxatives at the same time as opioid analgesics. However, the effectiveness of prophylactic laxatives on OIC has not been widely demonstrated. We therefore examined the incidence of OIC among patients with and without prophylactic laxatives within one week after initiating strong opioid analgesics, and the factors associated with the incidence of OIC. Methods: Eligible patients were adults with cancer for whom strong opioid analgesics were initiated after admission and who remained hospitalized for over a week. Propensity score matching analysis was used to compare outcomes after adjusting for patient background. Results: In total, 928 patients were enrolled, from which 536 were selected after propensity score matching analysis. The incidence of OIC in patients with prophylactic laxatives was not significantly different from that without prophylactic laxatives (48.1% vs 48.9%, odds ratio (OR) = 0.97, 95% confidence interval (CI): 0.69-1.36). In multivariable logistic analysis, age ≥65 years (OR = 1.53, 95% CI: 1.07-2.19) and Eastern Cooperative Oncology Group Performance Status (ECOG PS) ≥3 (OR = 1.69, 95% CI: 1.04-2.77) were associated with the incidence of OIC. Conclusion: Prophylactic laxatives do not affect the incidence of OIC in our study. Our results suggest that prophylactic laxatives are not necessarily required when initiating opioid therapy. In addition, we found that age ≥65 years and ECOG PS ≥3 were associated in our study with the incidence of OIC.