Cause-Specific Secular Trends and Prevention Measures of Post-Neonatally Acquired Cerebral Palsy in Victoria and Western Australia 1975-2014: A Population-Based Observational Study.

Aim: To describe the timing and causes of post-neonatally acquired cerebral palsy (PNN-CP) and map the implementation of relevant preventive strategies against cause-specific temporal trends in prevalence.

Methods: Data for a 1975-2014 birth cohort of children with PNN-CP (brain injury between 28 days and 2 years of age) were drawn from the Victorian and Western Australian CP Registers. Descriptive statistics were used to report causal events and timing. Poisson regression models were used to investigate the strength of evidence for cause-specific temporal trends in prevalence. Preventive strategies were mapped alongside cause-specific trends.

Results: Amongst 512 children, causes of PNN-CP included infections (31%, n = 157), head injuries (24%, n = 121) and cerebrovascular accidents (CVAs) (23%, n = 119). Infections were the only main causal group of PNN-CP that declined significantly (p = 0.014). Fifty two percent (n = 267) of the PNN-CP cohort acquired their brain injury before 6 months of age, the majority having an infectious cause (57%, n = 90). Improved clinical care and a range of preventive strategies, including childhood vaccination programs, occurred during this period.

Conclusion: Infants under 6 months are a priority group for preventive strategies for PNN-CP. Declining temporal trends were observed for PNN-CP caused by infection, and the causal subgroup of CVAs associated with surgery. Interventions aimed at further reducing the risk of head injury, CVAs and infections, are needed to reduce the prevalence of PNN-CP.