Motor development problems in infancy predict mental disorders in childhood: a longitudinal cohort study.

The purpose of this study is to examine whether motor development problems in infancy predicted mental disorders later in childhood, taking a wide array of potential confounding variables into consideration. This longitudinal study included an unselected study population of 33238 newborn children from the Copenhagen area, Denmark. Data on the predictor variable, motor development problems at 8-10 months of age, were obtained from the community health nurses' systematic evaluation of the child's motor development during a home visit and stored in the Child Health Database. Data on outcome, diagnosed mental disorders before the age of 8 years, were obtained from the Danish National Patient Register. Potential confounding variables were obtained from the Child Health Database, the National Birth Register and the Civil Registration System. The prevalence of motor development problems at 8-10 months of age was 19.3%; the incidence of any diagnosed mental disorder from 11 months of age to the 8th birthday was 4.0%. Motor development problems were associated with an increased risk of being diagnosed with a mental disorder before the 8th birthday, adjusted odds ratio (AOR) 1.47 (1.29-1.67). Motor development problems were associated with later neurodevelopmental disorders, AOR 1.77 (1.52-2.06), in particular 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 8-10 months of age were predictive of neurodevelopmental disorders before the 8th birthday. The findings call for clinical attention and more research on preventive potentials in the community child health care. WHAT IS KNOWN: • Children with ASD, ADHD and ID have high prevalence of early motor development problems. WHAT IS NEW: • Motor development problems in infancy predicted neurodevelopmental disorders before the 8th birthday. • This observation could improve early identification and prevention of mental health problems in childhood.

Social inequality in parent-infant relations: Epidemiological study of community nurse records.

Background: Some studies suggest that favourable socioeconomic circumstances are associated with better parent-child relations but the documentation of such an association is limited and inconsistent. Few studies focused on infancy, few studies relied on objective measurement of parent-infant relations, and few studies included more than one measurement of parent-infant relations in the first year of life. Aims: To report the prevalence of objectively measured problems in parent-infant relations during the first year of life and to examine the association between socioeconomic circumstances and parent-infant relations in an unselected community sample of infants. Methods: Cross-sectional study of a community sample of children from birth to 10 months in 15 municipalities in Denmark, n = 11,765. The exposure variables were population register data about socioeconomic circumstances: (a) parents' education, (b) family composition, (c) parents' origin, and (d) parents' occupational status. The outcome variable was the health visitor's concerns about the parent-infant relation assessed at four home visits from birth to 10 months after delivery. Results: The proportion of children with concerns about the parent-infant relation was 10.5%, 7.8% at one home visit and 2.8% at two or more home visits. Logistic regression analyses showed that all four indicators of socioeconomic circumstances were associated with concerns about the parent-infant relation in the first year of life. Conclusions: The risk of problematic parent-infant relations were significantly elevated among, children of immigrant parents, and children of parents with shorter education and not in education or work.

Difficulties falling asleep among adolescents: Social inequality and time trends 1991-2018.

Sleep problems in adolescence are increasingly common, and associated with adverse health and psychological outcomes. Adolescents' sleep problems may be related to the family's socioeconomic status, but studies are few and no study has examined whether social inequality in sleep problems changes as sleep problems become increasingly common. This study examined trends in difficulties falling asleep among adolescents in Denmark, whether this sleep problem was associated with socioeconomic status, and whether this association changed from 1991 to 2018. The study applied data from eight comparable surveys among 11-15 year olds in Denmark 1991-2018, the Danish arm of the international Health Behaviour in School-aged Children study, N = 30,002. The prevalence of daily difficulties falling asleep increased from 7.0% to 13.4% in 1991-2018 with higher frequencies among girls and younger adolescents. The odds ratio (95% confidence interval) for daily difficulties was 1.14 (1.05-1.24) in middle and 1.52 (1.37-1.69) in low compared with high socioeconomic status. The absolute social inequality in difficulties falling asleep was persistent in 1991-2018 whereas the relative social inequality may have decreased. The increasing prevalence and the social inequality in difficulties falling asleep among adolescents is a serious public health concern that calls for more attention and efforts.