Motor Development Problems in Infancy Predict Mental Disorders in Childhood: Longitudinal Child Cohort Study

Abstract The aim was to examine whether motor development problems in infancy predicted mental disorders later in childhood, taking a wide array of potential confounder variables into consideration. This longitudinal study included an unselected study population of 33,238 newborn children from the Copenhagen area in Denmark. Data on the predictor variable motor development problems at age 8-10 months was obtained from the community health nurses’ systematic evaluation of the child’s motor development problems during a home visit stored in the Child Health Database. Data on outcome, diagnosed mental disorders before age 8 years, was obtained from the Danish National Patient Register. The study included potential confounders obtained from the Child Health Database, the National Birth Register, and the Civil Registration System. The prevalence of motor development problems at age 8-10 months was 19.3% and the incidence of any diagnosed mental disorder from age 11 months to the 8th birthday was 4.0%. Motor development problems were associated with an overall increased risk of being diagnosed with a mental disorder before the 8th birthday, adjusted odds ratio (AOR) 1.47 (1.29-1.67), in particular diagnosed neuro-developmental disorders, AOR 1.77 (1.52-2.06), such as autism-spectrum disorders, AOR 1.63 (1.31-2.03), hyperactivity/ attention deficit disorders, AOR 1.29 (1.03-1.61) and disorders of intellectual disability, AOR 3.28 (2.39-4.49). Conclusion: Motor development problems as early at age 9-10 months are predictive of neurodevelopmental disorders at age 1-8 years. The findings call for clinical attention and more research in the preventive potentials in the community child health care.