Opioid dispensing after Cesarean delivery in British Columbia: a historical cohort analysis from 2004 to 2019

To describe postdischarge opioid dispensing after Cesarean delivery (CD) in 49 hospitals in British Columbia (BC) and assess opportunities for opioid stewardship.

Using the BC Ministry of Health's Hospital Discharge Abstract Database, we linked 135,725 CDs performed in 2004-2016 and 30,919 CDs performed in 2017-2019 (length of stay ≤ four days) by deidentified Personal Health Numbers to data on medications dispensed from all BC community pharmacies (PharmaNet). We excluded patients with cancer and those to whom opioids have been dispensed in the year before. We measured trends in annual percentages of patients dispensed opioids within seven days (opioid rate), with 95% confidence intervals (CIs), stratified by hospital and opioid type, adjusted for length of stay, and for autocorrelation within hospital using generalized linear modeling.

The opioid dispensation rate dropped from 31% (95% CI, 30 to 33) in 2004 to 16% (95% CI, 15 to 17) in 2016, where it remained through 2019. Five hospitals showed steep reductions from over 40% to under 10% within two to three years, but in most hospitals the opioid dispensation rate decreased slowly-11 had little reduction and three showed increases. Codeine dispensing dropped from 31% in 2004-2008 by 4% per year, while tramadol and hydromorphone dispensing rose. After 2015, rates were stable (hydromorphone, 8%; tramadol, 6%; codeine, 3%; and oxycodone, 0.5%).

After Health Canada's 2008 warning against codeine use by breastfeeding mothers, post-CD opioid dispensing declined disjointedly across BC hospitals. Rates did not decrease further after the opioid overdose epidemic was declared a public health emergency in BC in 2016. The present study highlights opportunities for quality improvement and opioid stewardship through monitoring using administrative databases.