Variation in Discharge Opioid Prescribing After Vaginal Births

OBJECTIVE

Prescribed postpartum opioid use is associated with persistent use and other serious opioid-related events such as overdose and death.^1,2 Between 10–50% of women receive opioid prescriptions after vaginal births depending on U.S. region³, yet little is known about hospital-level variation in prescribing practices. Our objective was to examine opioid prescribing rates for women after vaginal births at Tennessee hospitals and their association with hospital characteristics.

STUDY DESIGN

We conducted a cross-sectional study using Tennessee Medicaid data supplemented with state hospital discharge data and birth certificates. We identified women aged 15–44 years with a vaginal birth at a Tennessee hospital between 1/1/2014 and 9/30/2015, and no evidence of opioid use disorder (ICD-9 codes 304.0, 304.7, 305.5, 965.0; any opioid, buprenorphine or methadone prescription) and continuous Medicaid enrollment during the 180 days prior to delivery. The Vanderbilt University Institutional Review Board approved the study.

For each hospital, we estimated the opioid prescribing rate as the percentage of vaginal births with an opioid prescription fill within 5 days of hospital discharge. We also estimated opioid prescribing rates after excluding deliveries with complications (severe maternal morbidity⁴, 3^rd or 4^th degree perineal lacerations or unplanned operations, as recorded in birth certificate data). To examine whether hospital characteristics were associated with prescribing rates, we used multivariable linear regression to assess the influence of teaching status, ownership, region, and licensed beds, which were obtained from the American Hospital Association Annual Survey and State Hospital Joint Annual Reports. The model also included average patient age and proportion white race among study patients at each hospital, and the proportion of all births that were covered by Medicaid (from birth certificate data).

RESULTS

We identified 26,428 vaginal births (25,676 [97%] without complications) at 62 hospitals that met selection criteria. At the hospital level, the median age of study patients was 23.9 (interquartile range [IQR] 23.4–24.5) years; the proportion of white study patients was 86% (IQR 64–96%); and the proportion of births covered by Medicaid was 64% (IQR 51–77%).

Opioid prescribing rates after vaginal birth varied widely from 3% to 84% (median 51% [IQR 32–69%]) across study hospitals (Figure). After excluding deliveries with complications, rates also ranged from 3 to 84% (median 52% [IQR 32–69%]). In the multivariable model, the opioid prescribing rate decreased by 6.3% (95% CI −9.3, −3.2) for every 10% increase in the proportion of births covered by Medicaid, after accounting for other hospital characteristics. Prescribing rate was not significantly associated with other hospital-level variables.

Figure.

Proportion of vaginal births with opioid prescription fills within 5 days of discharge by hospital, Tennessee Medicaid (2014–2015)

All hospitals (n=62) are anonymized and sorted by discharge opioid prescription rate; Wald 95% confidence intervals are shown for each proportion

CONCLUSIONS

In this study of Medicaid-enrolled women, there was greater than 20-fold variation in discharge opioid prescribing rates after vaginal births, even after excluding complicated deliveries. Hospitals with greater proportion of Medicaid-covered births had lower opioid prescribing rates. Further studies are needed to better understand potential underlying factors such as differential treatment of pain in certain populations.⁵ While we anticipate that prescribing rates may have changed since 2015, these estimates can serve as an important benchmark as differential opioid prescribing practices and postpartum management among hospitals remains an ongoing and pressing concern.