Trends in prevalence and spatiotemporal distribution of gastroschisis in Arkansas, 1998-2015

Background Arkansas (AR) had the highest prevalence of gastroschisis in a recent study including 15 U.S. states. Our objective was to evaluate trends in prevalence and the spatiotemporal distribution of gastroschisis in AR. Methods Infants with gastroschisis, born 1998-2015, were identified from the Arkansas Reproductive Health Monitoring System. Birth record data were used as denominators for calculations. Maternal residence at delivery was geocoded for spatial analyses. Annual prevalence rates (PRs) were calculated. Joinpoint regression analysis was performed to examine trends in gastroschisis and report the annual percent changes (APCs) in PRs. Spatiotemporal analyses identified counties with unusually high PRs of gastroschisis. Poisson regression, including county, year, and county*year indicators, was fit to evaluate the PRs of gastroschisis, while adjusting for county-level maternal variables. Results We identified 401 cases of gastroschisis among 694,459 live births. The overall PR of gastroschisis was 5.8/10,000 live births. The prevalence of gastroschisis had a significant APC of +5.3% (p < .0001) between 1998 and 2012, followed by a nonsignificant yearly average decrease of -17% through 2015 (p= 0.2). The Emerging Hot Spot Analysis and SaTScan identified an overlapping five-county cluster from 2006 to 2013. Poisson regression model, including county (inside vs. outside cluster), time (before vs. after 2006), and county*time indicators, was fit to evaluate the PRs of gastroschisis. The model did not confirm the presence of a spatiotemporal cluster, once it adjusted for county-level maternal characteristics (p=.549). Conclusion Close monitoring of rates of gastroschisis is warranted to determine if the PRs of gastroschisis continue to decline in AR.