Characteristics, determinants, and frequency of persistent use among
prescription opioid episodes initiated postpartum: a population-based
cohort study from British Columbia, Canada
Abstract
Objective: To determine the characteristics, determinants, and
persistent use for prescription opioid episodes initiated postpartum in
British Columbia (BC), Canada. Design: Population-based cohort,
2008-2015. Setting: Linked administrative databases including
outpatient and inpatient visits and outpatient prescription
dispensations for all individuals in BC tested for hepatitis C or HIV.
Population: Opioid-naïve individuals aged 13-49 with a delivery
hospitalization record. Methods: We used modified Poisson
regression to estimate risk ratios (RR) for pre-pregnancy
characteristics and adjusted RR (aRR) for delivery characteristics
adjusted for potential confounders. Main Outcome Measures: All
and persistent (≥90 days) prescription opioid episodes initiated
postpartum. Results: Among 292,684 eligible deliveries, 8.8%
(95% CI: 8.7% to 8.9%) initiated a postpartum prescription opioid
episode and 0.4% (0.4%- 0.5%) had a persistent episode. Persistent
prescription opioid episodes were more frequent among cesarean vs.
vaginal deliveries (1.0% vs. 0.2%, aRR 5.1 [4.6-5.8]). Opioid
episodes varied regionally and declined from 12.8% in 2008 to 7% in
2012-2015. Persistent prescription opioid episodes were associated with
pre-pregnancy: mental illness history (RR 2.4 [1.9-3.1]),
psychotropic medication use (RRs 3.6-4.9), chronic pain (RR 2.7
[1.8-3.9]) and alcohol misuse (4.6 [2.2-9.7]), and delivery
complications: intensive care unit admission (aRR 5.4 [3.3-8.9]),
postpartum hospital readmission (aRR 3.9 [3.2-4.8]), and vaginal
deliveries with hysterectomy (aRR 23.7 [6.1-91.8]) or tubal
ligation/salpingectomy (aRR 14.6 [5.4-39.4]). Conclusions:
Persistent prescription opioid episodes were initiated following 0.4%
of deliveries. Postpartum pain management strategies should consider the
strong associations between pre-pregnancy and delivery characteristics
and persistent prescription opioid episodes initiated postpartum.