Effect of comorbid allergic diseases on attention-deficit hyperactivity disorder symptoms and sleep: A cross-sectional study

Introduction: Recent studies have shown a close relationship between attention-deficit hyperactivity disorder (ADHD) and allergic diseases in children. Regrettably, few studies have investigated the effect of comorbid allergies on ADHD symptoms and sleep, in particular, it is unclear whether comorbid allergic conditions further exacerbate sleep problems in children with ADHD. Objective: To investigate the effect of comorbid allergic on symptoms and sleep in children with ADHD. Methods: This was a cross-sectional study, 222 ADHD children (aged 6-14 years) were enrolled in, of whom 93 had allergic diseases and 129 without allergic diseases. Collected all ADHD symptom severity and functional impairment scales, including: Swanson, Nolan and Pelham (SNAP) scale, Integrated Visual and Auditory Continuous Performance Test (IVA-CPT), Conners Parents Symptom questionnaire (PSQ) and Weiss Functional Impairment Rating Scale-Parent Form (WFIRS-P). Every guardian of children diagnosed with ADHD is required to complete the Children's Sleep Habits Questionnaire (CSHQ). Results: Compared to ADHD children without allergic diseases, we observed significantly higher hyperactivity and impulsivity scores on the SNAP-IV, higher hyperactivity index and impulsivity index on the PSQ, and higher risky activities on the WFIRS-P in ADHD children with comorbid allergic diseases (all p < 0.05). CSHQ total score and sleep disordered breathing were particularly prominent in ADHD children with comorbid allergic diseases (all p < 0.05), and changes in CSHQ correlate with ADHD symptoms and functional impairment. Further analyses revealed that ADHD symptoms and sleep did not worsen with increasing number of comorbid allergic diseases (all p > 0.05). The primary influence on ADHD symptoms and sleep was the type of allergic diseases, where food allergies predominantly influence ADHD symptoms, including attention deficit disorder and hyperactivity disorder (all p < 0.05); allergic rhinitis notably impacts parasomnias, sleep disordered breathing (all p < 0.05); and allergic asthma significantly affects sleep anxiety, daytime sleepiness, and sleep disordered breathing in children with ADHD (all p < 0.05). Conclusion: The presence of comorbid allergic diseases affects both the hyperactivity and impulsivity symptoms of ADHD and sleep disordered breathing, predominantly influenced by the type of the allergic diseases.