Utilization, adherence, and outcomes of 17-alpha hydroxyprogesterone caproate for recurrent spontaneous preterm birth...

To describe the use of and adherence to 17-alpha hydroxyprogesterone caproate (17-OHPC), explore factors associated with its utilization and adherence, and to investigate the outcomes of 17-OHPC in a real-world setting.

The Decision Resources Group (DRG) database (1 January 2012-31 December 2017) was used to identify women with diagnosis of "history of preterm labor", aged 16-50 years old, had a singleton gestation, were continuously enrolled for at least 6 months and 9 months before and after the index date, respectively, and had a delivery outcome recorded. Adequate adherence was defined and compared using two approaches: (1) patients receiving at least 10 injections of 17-OHPC; (2) number of received injections/eligible number of injections ≥0.7. The outcome of 17-OHPC was evaluated by the incidence rate of preterm birth (PTB). Bivariate tests compared patients' characteristics with their use of and adherence to 17-OHPC, and examined the associations between 17-OHPC utilization and incidence of diabetes or hypertension. Stepwise logistic regression was conducted to assess the effect of adherence on the delivery outcome.

Of 28,339 patients meeting study criteria, 2585 (9.1%) had ≥1 claim for 17-OHPC. An increasing trend of utilization was observed from 2012 to 2017 (7.6-13.1%). The utilization rate was highest in the Southwest US (13.8%) (p < .001). Commercial insurance patients (9.6%) were more likely to use 17-OHPC than Medicaid patients (7.9%) (p < .001). Patients with higher Charlson Comorbidity Index (CCI) scores were less likely to use 17-OHPC. Of women prescribed 17-OHPC, 792 (30.6%) and 424 (16.4%) were adherent using two definitions, respectively. No difference in PTB rate was observed between adherers and non-adherers (definition 1: aOR = 0.97, 95% CI = 0.81-1.16; definition 2: aOR = 1.18, 95% CI = 0.95-1.48). No association was found between 17-OHPC and incidence of diabetes (p = .96); however, use of 17-OHPC was associated with a lower incidence rate of hypertension (p = .002).

17-OHPC utilization and adherence rates remain low. Insurance type and geographic region were associated with both utilization and adherence. There was no association between 17-OHPC adherence and effectiveness. More evidence is needed to determine if the use of 17-OHPC is advantageous in a sub-group of patients.