Differences in outpatient, emergency, and inpatient use among pregnant women with a substance-related diagnosis.

Background: As a vulnerable population, pregnant women with a substance-related diagnosis (ie, substance use, misuse, or dependence) may use healthcare disproportionately.

Objective: The primary goal of this study was to evaluate the differences in the use of outpatient clinical visits, emergency department visits, and inpatient days in the hospital among women with and without a substance-related diagnosis during the antepartum period.

Study Design: This retrospective study retrieved electronic health record data on women (age, 18-44 years) who delivered a single live birth or stillbirth at ≥20 weeks of gestation from April 1, 2012, to September 30, 2019. Imbalance in measured maternal sociodemographic and obstetrical characteristics between women with and without a substance-related diagnosis was attenuated using propensity score matching on key demographic characteristics (eg, age), yielding a matched 1:1 sample. Unadjusted and adjusted logistic regressions models were used to determine the association between a substance-related diagnosis and outpatient visits, emergency visits, and inpatient days.

Results: From the total sample (n=16,770), the matched cohort consisted of 1986 deliveries. Of these, most were White (51.0%), or mixed or of some other race (31.1%). The mean age was 29.8 (standard deviation, 5.6). A substance-related diagnosis was identified in 993 women (50%) because of matching. Women with a substance-related diagnosis were more likely to have ≤10 outpatient visits than women without a substance-related diagnosis (adjusted odds ratio, 1.81 [95% confidence interval, 1.44-2.28]; P<.0001). Alcohol-, opioid-, and stimulant-related diagnoses were independently associated with ≤10 outpatient visits (adjusted odds ratio, 3.16 [95% confidence interval, 1.67-6.04]; P=.0005; adjusted odds ratio, 3.02 [95% confidence interval, 1.79-5.09]; P<.0001; adjusted odds ratio, 2.18 [95% confidence interval, 1.39-3.41]; P=.0007, respectively). Women with a substance-related diagnosis were more likely to have ≥1 emergency visit than women without a substance-related diagnosis (adjusted odds ratio, 1.36 [95% confidence interval, 1.00-1.85]; P<.0001). Opioid-, stimulant-, and nicotine-related diagnoses were independently associated with ≥1 emergency visit (adjusted odds ratio, 2.28 [95% confidence interval, 1.09-4.77]; P=.0287; adjusted odds ratio, 2.01 [95% confidence interval, 1.07-3.78]; P=.0301; adjusted odds ratio, 3.38 [95% confidence interval, 1.90-6.02]; P<.0001, respectively). Women with a substance-related diagnosis were more likely to have ≥3 inpatient days than women without a substance-related diagnosis (adjusted odds ratio, 1.69 [95% confidence interval, 1.07-2.67]; P=.0256). Opioid-, stimulant-, and nicotine-related diagnosis were independently associated with ≥3 inpatient days (adjusted odds ratio, 3.52 [95% confidence interval, 1.42-8.75]; P=.0067; adjusted odds ratio, 3.51 [95% confidence interval, 1.31-9.34]; P=.0123; adjusted odds ratio, 2.74 [95% confidence interval, 1.11-6.73]; P=.0285, respectively).

Conclusion: Women with a substance-related diagnosis during the antepartum period who delivered a single live birth or stillbirth at ≥20 weeks of gestation were experiencing fewer outpatient visits, more emergency department visits, and more inpatient days than women without a substance-related diagnosis. The type of substance-related diagnosis (eg, alcohol, opioids, stimulants, or nicotine) was associated with different patterns of healthcare use. The results from this study have reinforced the need to identify substance-related diagnoses in pregnant women early to minimize disproportionate healthcare service utilization through intervention and treatment.