The relationship between financial difficulty and childhood symptoms of attention deficit/hyperactivity disorder: a UK longitudinal cohort study

PURPOSE: Attention deficit/hyperactivity disorder (ADHD) is associated with socioeconomic status (SES), in that children who grow up in low SES families are at an increased risk of ADHD symptoms and diagnosis. The current study explores whether different levels of ADHD symptoms are associated with prior changes in the SES facet of financial difficulty. METHODS: Using the Avon Longitudinal Study of Parents and Children (ALSPAC), we examined symptoms of ADHD measured by the Strengths and Difficulties Questionnaire (SDQ) hyperactivity subscale in relation to parent-reported changes in financial difficulty, grouped into four repeated measures at four time points across childhood; (n = 6416). A multilevel mixed-effects linear regression model with an unstructured covariance matrix was used to test whether different patterns of financial difficulty were associated with subsequent changes in ADHD symptoms. RESULTS: Families who had no financial difficulty had children with a lower average ADHD symptom score than groups who experienced financial difficulty. Children whose families stayed in financial difficulty had higher mean ADHD symptom scores than all other groups (No difficulty mean SDQ hyperactivity 3.14, 95% CI 3.07, 3.21, In difficulty mean SDQ hyperactivity 3.39, 95% CI 3.28, 3.45, p < 0.001). Increasing or decreasing financial difficulty predicted mean symptom scores lower than those of the in difficulty group and higher than the no difficulty group. CONCLUSIONS: Our findings contribute to the building evidence that SES may influence the severity and/or impairment associated with the symptoms of ADHD, however the effects of SES are small and have limited clinical significance. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (10.1007/s00127-017-1453-2) contains supplementary material, which is available to authorized users.