Objective: This study describes the incidence of neonatal abstinence syndrome (NAS) in Ontario, Canada by year and health region from 2003 to 2016.
Design: The incidence of NAS diagnoses per 1,000 live births was calculated for the 36 local public health agency regions in Ontario from 2003 to 2016 using retrospective hospital admissions data. Infants with a diagnosis of NAS were identified using ICD-10 code P961. Local public health agency level data were aggregated and analyzed by geographic region and by Statistics Canada 2015 Peer Groups.
Results: The incidence of NAS in Ontario increased from 0.99 per 1,000 live births in 2003 to 5.94 per 1,000 live births in 2016. There were major differences in NAS incidence by geography, North Western Ontario had the greatest incidence across all years. Health regions with a rural and population center mix or mostly rural population had greater incidence rate of NAS compared to health regions with high density population centers.
Conclusions: The incidence of NAS has dramatically increased across Ontario in the last decade. Actions should be taken to combat the continued increase in NAS rates, especially in health regions with disproportionately high incidence of NAS.