Indication Creep of Antenatal Late Preterm Steroids

Abstract

While antenatal corticosteroids (ACS) administered in the late preterm period have been shown to reduce respiratory morbidity, this finding was demonstrated in a well-designed randomized controlled trial (ALPS) with strict inclusion/exclusion criteria that may differ from clinical practice. The aim of this study was to investigate whether there has been indication creep since use of late preterm ACS became standard of care. Retrospective cohort study of pregnant women who received late preterm ACS between 2016 and 2019 were identified and separated into epochs of 2016-2017 and 2018-2019 based upon year of exposure. The primary outcome was rate of inappropriate ACS exposure, defined as non-adherence to the inclusion/exclusion criteria of the ALPS trial. Secondary outcomes were rates of non-optimal ACS exposure (delivery >7 days from ACS or term delivery). Logistic regression was used to generate adjusted odds ratios (aOR) between epochs for the primary outcome adjusting for confounders. There were 660 women who received late preterm ACS during the study period with 229 (34.6 %) deemed inappropriate exposures. The most common reason for inappropriate treatment was PPROM (29.0%) with exclusionary cervical exam or contraction frequency. No difference was observed in inappropriate ACS exposure between epochs (aOR 0.83, CI 0.59-1.2). However, there was a reduction in non-optimal exposure over time (aOR 0.67, 0.47-0.97) . Women receiving inappropriate ACS were more likely to deliver at term if indicated for maternal/fetal status (50.0% vs 19.5%; p<.001) and preterm labor (66.0% vs 41.9%; p=.015). Further, inappropriate exposure in PTL had higher rates of exposure latency >7 days (62.3% vs 39.1%; p=.006) with a longer latency to delivery (3 vs 16 days; p<.001). Over one third of women received late preterm ACS for an indication that could be classified as indication creep. Depending on indication, inappropriate administration is associated with higher rates of non-optimal exposure.

Late preterm antenatal steroid use and infant outcomes in a single center

“…In the study by McElwee, et al, the highest rate of inappropriate exposure was for without cervical change (10), which is in contrast to our data where the No AS group had a higher incidence of PPROM compared to those who received AS. Pregestational diabetes was an exclusion criteria for ALPS study and SMFM recommendations, and our cohort expectedly showed a signi cantly larger proportion of diabetes in the No AS group compared to those given AS.…”

“…Only 4.5% of our AS group had pregestational diabetes, which was similar to the ndings of the cohort by McElwee, et al, where only 3% of inappropriate AS exposures were in the setting of pregestational diabetes. (10) This is in contrast to the ndings of Battarbee, et al, whose survey showed that greater than 50% of the providers reported administering betamethasone in the setting of poorly controlled diabetes or diabetes on insulin. ( 9)…”

“…singleton pregnancies with a high probability of delivering within 7 days of randomization; excluding those expected to deliver in less than 12 hours for any reason, pregestational diabetes, known major fetal anomalies, or those who had previously received AS during pregnancy) (9). Concern for "indication creep" was also raised by McElwee, et al, when they found 229 out of 660 (35%) women in their cohort from 2016 to 2019 who received late preterm AS were deemed "inappropriate exposures" using recommended criteria (10). There is a need for better understanding of the practice patterns at various institutions and the associated neonatal outcomes associated with AS use.…”

Late preterm antenatal corticosteroids in singleton and twin gestations: a retrospective cohort study

“…Obstetric practices, including those at our own institution, increasingly administered betamethasone for women at risk of late preterm delivery, within and outside of the criteria specified in the ALPS trial [ 7 – 9 ]. Though administration of ACS for twins and other deviations have been documented, the benefits remain unclear [ 9 , 10 ].…”

“…Obstetric practices, including those at our own institution, increasingly administered betamethasone for women at risk of late preterm delivery, within and outside of the criteria specified in the ALPS trial [ 7 – 9 ]. Though administration of ACS for twins and other deviations have been documented, the benefits remain unclear [ 9 , 10 ]. Twins and singletons may have biological and pharmacokinetic differences [ 11 ], so findings from the ALPS trial may not be generalizable to twin gestations [ 12 , 13 ].…”