723: Differences in long-term morbidities between the first and the second born twins.

Abstract

Recent studies have reported an increased risk of short-term neonatal morbidity among second versus first-born twins in term and late preterm twin populations. The present study was aimed to investigate whether the second twins are also at an increased risk for long-term pediatric morbidity. In this population-based retrospective cohort study, the incidence of long-term (up to the age of 18 years) hospitalizations due to cardiovascular, neurological, respiratory, and infectious pediatric morbidities was investigated. A comparison was performed between the first and second born diamniotic twins. Deliveries occurred between the years 1991 and 2014 in a tertiary referral hospital. The risk for long-term morbidities in the twins was based on the hospital’s pediatric database and a pre-defined set of ICD-9 codes. Kaplan-Meier survival curves were constructed to compare cumulative morbidities and Cox proportional hazards models were used to control for confounders. In the current study 1919 sets of twins were inclucded. The total long-term hospitalizations, up to 18 years of age, due to cardiovascular (0.8% vs 0.6%, P=0.18), respiratory (4.0% vs 3.7%, P=0.29), neurologic (3.2% vs 3.6%, P=0.31) and infectious hospitalizations (7.5%% vs 7.5%, P=0.13) were comparable between the first and the second born twins (Table). Likewise, the Kaplan-Meier survival curves showed no difference in the cumulative incidence of total cardiovascular, respiratory, neurologic or infectious long-term hospitalizations between first and second born twins (Figure). In the Cox regression models adjusting for mode of delivery and gestational age, adjuted hazards ratios (aHR) were comparable between first and second born twin regarding cardiovascular (aHR=0.89, 95% CI 0.76-1.05, P=0.18), respiratory (aHR=1.01, 95% CI 0.94-1.06, P=0.91), neurological (aHR=1.21, 95% CI 0.84-1.74, P=0.30) or infectious morbidities (aHR=1.08, 95% CI 0.97-1.20, P=0.13). The second-born twin does not seem to be at an increased risk for long-term pediatric morbidity. Cumulative incidence of hospitalizations up to 18 years of age due to cardiovascular, neurological, respiratory, and infectious pediatric morbidities is comparable between the first and second born twin.View Large Image Figure ViewerDownload Hi-res image Download (PPT)