Incidence of Nonsynostotic Plagiocephaly and Developmental Disorders.

IMPORTANCE

This is the first population-based study quantifying the incidence of nonsynostotic positional plagiocephaly and/or brachycephaly (PPB) in infancy and its association with developmental disorders.

OBJECTIVE

To report the incidence of PPB before age 1 year, the incidence of craniosynostosis, and the percentage of children with PPB diagnosed with a developmental disorder by age 7 years.

DESIGN, SETTING, AND

PARTICIPANTS

This was a retrospective, population-based cohort study of children in the Rochester Epidemiology Project (REP) born in Olmsted County, Minnesota, from January 1, 2008, through December 31, 2012, with follow-up through age 7 years. Data were analyzed from March 2021 to April 2024.

EXPOSURE: Physical examination detecting cranial deformity.

MAIN OUTCOMES AND MEASURES: The primary outcome was the incidence of PPB. Secondary outcomes were the incidence of craniosynostosis and the percentage of children with PPB diagnosed with a developmental disorder by age 7 years.

RESULTS

Of 9909 infants (5084 [51.3%] male; 9205 [92.9%] born at term and 704 [7.1%] born preterm) included in the study, 575 had PPB, for a PPB incidence of 5.8% (95% CI, 5.3%-6.3%). The incidence of PPB was 5.3% (95% CI, 4.8%-5.8%) in term infants vs 11.8% (95% CI, 9.4%-14.6%) in preterm infants. The incidence of craniosynostosis was 0.16% (95% CI, 0.09%-0.26%). A developmental disorder was known or suspected in 4.2% (95% CI, 2.7%-6.2%) of infants at the time of PPB diagnosis; among 402 infants with PPB and follow-up through age 7 years, 30 (7.5%; 95% CI, 5.0%-10.7%) had a confirmed developmental disorder by 7 years of age. The prevalence of autism spectrum disorder (ASD) in children with a history of PPB who were followed up to age 7 years was 2.2% (9 of 402 children).

CONCLUSIONS AND RELEVANCE: This study found that only a small percentage of the infants had positional head deformity significant enough to be documented and/or referred for subspecialty evaluation, and only a small subset of these children went on to have a developmental disorder in childhood. This information is helpful for counseling families about their child's developmental risk at time of PPB diagnosis.