Prevalence and temporal trends of cerebral palsy in children born from 2002 to 2017 in Ontario, Canada: Population-based cohort study.

AIM: To examine the prevalence and temporal trends of cerebral palsy (CP) overall and by population characteristics.

METHOD: We identified 2 110 177 live births born in the province of Ontario, Canada, between 2002 and 2017 using administrative health data and estimated CP prevalence in children aged 0 to 16 years overall and by specific population characteristics. We also examined temporal trends in CP rates - overall and by characteristics - in young children (0-4 years) by their year of birth between 2002 and 2013 (n=1 587 087 live births) to allow for an equal follow-up time (4 years and 364 days) for all children.

RESULTS

Overall CP prevalence among children aged 0 to 16 years was 2.52 (95% confidence interval 2.45-2.59) per 1000 live births. CP rates in ages 0 to 4 years peaked at 2.86 in 2007 births, but steadily declined afterwards to 1.94 per 1000 live births in 2013. CP rates were higher in children born preterm, small for gestational age, males, multiples, children with congenital malformations, and in children of young (<20 years), old (≥40 years), primiparous, or grand multiparous (≥4) mothers; differences by these characteristics decreased over time. We observed socioeconomic disparities in CP rates that persisted over time.

INTERPRETATION: Despite the decreasing trend of CP rates overall, CP rates varied by the child and maternal characteristics over time.

WHAT THIS PAPER ADDS: Overall cerebral palsy (CP) prevalence was 2.5 per 1000 live births among children born from 2002 to 2017. CP prevalence peaked in children born in 2007 then steadily decreased between 2007 and 2013. Changes in CP rates varied over time by child and maternal characteristics. Socioeconomic inequalities in CP persisted and remained stable over the study period.