Association between 5-min Apgar score and attention deficit hyperactivity disorder: a Scotland-wide record linkage study of 758,423 school children

BACKGROUND: Attention-deficit hyperactivity disorder (ADHD) affects around 1 in 20 children and is associated with life-long sequelae. Previous studies of the association between Apgar score and ADHD have reported inconsistent findings. METHODS: Record linkage of maternity, prescribing and school pupil census databases was used to conduct a population e-cohort study of singleton children born in Scotland and attending school in Scotland at any point between 2009 and 2013. Binary logistic regression analysis was used to investigate the association between 5-min Apgar score and treated ADHD adjusting for sociodemographic and maternity confounders. RESULTS: Of the 758,423 children, 7,292 (0.96%) received ADHD medication. The results suggested a potential dose–response relationship between Apgar score and treated ADHD independent of confounders. Referent to an Apgar score of 10, risk of treated ADHD was higher for scores of 0–3 (adjusted OR 1.76, 95% CI 1.32–2.34), 4–6 (adjusted OR 1.50, 95% CI 1.21–1.86) and even 7–9 (adjusted OR 1.26, 95% CI 1.18–1.36) which are traditionally considered within the normal range. CONCLUSIONS: In addition to reinforcing the need to maximise Apgar score through good obstetric practice, the findings suggest that Apgar score may be useful in predicting future risk of ADHD and therefore facilitating early diagnosis and treatment.