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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.

Background Mental disorder in childhood is an important public health issue. We aimed to examine the prospective association between parental education at childbirth and diagnosed mental disorders in young children and explore whether this association was mediated or modified by parent–child relations in infancy. Methods Prospective cohort study of all newborn was from 2002 to 2010 from 16 municipalities in the capital region of Copenhagen, Denmark, with follow-up until their 8th birthday, N = 40 762. Baseline data included information from national population registers and from health visitors’ records at child aged 0 to 10 months. Outcome variable: any mental disorder diagnosed at hospital from age 11 months to 8 years. Results Low parental education was predictive of diagnosed child mental disorder, adjusted odds ratio (AOR) = 1.83 (95% CI 1.49–2.23). Problematic parent–child relation at age 8–10 months was also predictive of mental disorder, AOR = 2.06 (1.57–2.70) but did not mediate the association between parental education and mental disorder. AOR for mental disorders was 3.24 (2.03–5.16 for the combination vocational training and problematic parent–child relation and 2.49 (1.42–4.38) for the combination primary school and problematic parent–child relation. Conclusions Low parental education and problematic parent–child relation were independent risk factors for diagnosed mental disorders in the age span of 11 months to 8 years.

To examine whether motor development problems in infancy predicted mental disorders later in childhood, taking a wide array of potential confounding variables into consideration. Methods: This longitudinal study included an unselected study population of 33,238 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.Results: 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 8 th birthday was 4.0%. Motor development problems were associated with an increased risk of being diagnosed with a mental disorder before the 8 th 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 8 th birthday. The findings call for clinical attention and more research on preventive potentials in the community child health care.

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.