Trends in opioid dispensing after common abdominal and orthopedic surgery procedures in British Columbia: a retrospective cohort analysis

Purpose Postdischarge opioid prescriptions are reportedly much higher in Canada than in other countries. To assess potentially contributing factors, we examined trends after abdominal and orthopedic surgeries in British Columbia (BC). Methods Using the BC Ministry of Health's databases on physician billings, hospital discharge abstracts, and medication dispensations in community pharmacies for the period 2003-2016, we assembled a cohort of 263,056 patients who received laparoscopic appendectomy (LA, 11%), laparoscopic cholecystectomy (LC, 30%), open inguinal or femoral hernia repair (IHR, 20%), total hip arthroplasty (THA, 18%), or total knee arthroplasty (TKA, 22%). Adjusting for covariates using generalized linear modeling, we measured trends in percentages of patients dispensed opioids postdischarge (opioid rate) within 30 days after surgery, by surgery type, opioid type, prior use, surgeon, and trends in morphine milligram equivalents of first dispensations (MME) with 95% confidence intervals (CI). Results Opioid dispensation rates rose steadily. Mean annual increases were 1.7% in LA; 1.3% in LC; 0.8% in IHR; 0.9% in THA; and 0.8% in TKA. By 2016, rates were 69% in LA; 76% in LC; 81% in IHR; 88% in THA; and 94% in TKA. Codeine dispensations fell 2.4% (abdominal) and 3.1% (orthopedic) per year while tramadol dispensations increased 3.6% (abdominal) and 1.7% (orthopedic). Hydromorphone dispensations increased 2.9% per year (orthopedic); oxycodone was level at 22% between 2007 and 2014, but then fell. The mean MME rose 8 mg.yr(-1) (95% CI, 7 to 9) (abdominal) and 61 mg.yr(-1) (95% CI, 58 to 64) (orthopedic). Variation in rates was greater among abdominal than orthopedic surgeons. Conclusion Rising opioid dispensation rates, together with shifts to prescribing higher MME opioids, doubled MME per patient in first dispensations postdischarge after abdominal or orthopedic surgery from 2003 to 2016 in BC.