Codeine Shopping Behavior in a Retrospective Cohort of Chronic Noncancer Pain Patients: Incidence and Risk Factors.

ABSTRACT

Codeine is a widely used opioid analgesic but studies on its misuse in chronic noncancer pain (CNCP) are still lacking. The aim of this study was to assess the incidence of codeine shopping behavior in CNCP patients and to identify the associated risk factors. This was a population-based retrospective cohort study from the French health insurance claims database from 2004 to 2014. The main outcome was the one-year incidence of codeine shopping behavior defined as ≥1 day of overlapping prescriptions written by ≥2 different prescribers and filled in ≥3 different pharmacies. A total of 1,958 CNCP patients treated with codeine were included, with a mean age of 62.7 ± 16.1 years, 36.8% men. The 1-year incidence rate of codeine shopping behavior was 4.03% (95% confidence interval [CI], 3.07-5.28). In multivariate analysis, risk factors associated with shopping behavior were younger age (≤40 years) (hazard ratio [HR] = 7.29; 95% CI, 4.28-12.42), mental health disorders (HR = 2.25; 95% CI, 1.08-4.67), concurrent use of anxiolytic benzodiazepines (HR = 3.12; 95% CI, 1.55-6.26), and previous use of strong opioids (HR = 2.94; 95% CI, 1.24-6.98). The incidence of codeine shopping behavior in CNCP patients was 4% and risk factors identified were shared with those of opioid abuse. PERSPECTIVE Shopping behavior for codeine was not infrequent in CNCP patients. The risk factors identified in this study are similar to those identified for opioid abuse in other studies. Appropriate use of codeine from the perspectives of patients and healthcare providers should be encouraged.