Sleep Problems in Children with Anxiety and Attention Deficit Hyperactivity Disorders

Abstract

Objective: The aim of this thesis is to examine sleep problems in a clinical sample of children with anxiety and attention deficit/hyperactivity disorder (ADHD). The more specific aims are to investigate the frequency, the associations with behavioral and attentional functioning, and the persistence of sleep problems (both overall sleep problems and types of sleep problems). The sleep problems of children in the clinical sample are compared to those of a group of nonreferred children. The thesis also examines the influence of comorbidity on the frequency of sleep problems and explores possible predictors of persistence of sleep problems in the group of referred children.<br><br> Methods: The total sample consisted of 141 children aged 7–13 years, 51 girls and 90 boys, comprising 105 children referred to two child and adolescent outpatient clinics and 36 nonreferred children recruited as controls. The clinical sample was recruited from 421 consecutive referrals to the clinics, and the children were eligible for inclusion if they met diagnostic criteria for an anxiety disorder and/or ADHD after diagnostic interview with the parents, given no exclusion criteria applied. The clinical sample was grouped as follows: anxiety disorders without comorbid ADHD (ANX, n = 41), ADHD and no comorbid anxiety disorder (n = 39), anxiety disorders and ADHD (ANX+ADHD, n = 25). Of the 141 children participating at the initial assessment (T1), 76 referred and 31 nonreferred children were retained at the follow-up assessment after about 18 months (T2), giving an overall attrition rate of 24.1%. Diagnoses were assessed at T1 with parental interviews using the Kaufman Schedule for Affective Disorders and Schizophrenia present and lifetime version (Kiddie-SADS-PL). Sleep problems were assessed with mother reports on the Children’s Sleep Habit Questionnaire (CSHQ) at both T1 and T2. Attention was assessed at T1 by the Attention Network Test for children (ANT). Emotional and behavioral problems were assessed at T1 by teacher reports on the Achenbach System of Empirically Based Assessment, Teacher Report Form (ASEBA TRF).<br><br> Results: Referred children were reported to have more total sleep problems compared to nonreferred controls, and children in the ANX and ANX+ADHD groups more than children in the ADHD group. As to types of sleep problems, children in the ANX and ANX+ADHD groups had more bedtime resistance, sleep duration problems, sleep anxiety, parasomnias, and more daytime sleepiness compared to controls. Children in the ADHD group had more sleep disordered breathing problems and more daytime sleepiness compared to the controls. Children in the ANX group had more bedtime resistance problems than children in the ADHD group, and children in the ANX+ADHD group more night waking than the other groups of children. Comorbidity with other axis I disorders did not influence the frequency of total sleep problems among the referred children.<br> A higher reported frequency of overall sleep problems was associated with reduced efficiency of attentional functioning for both referred and nonreferred children, and daytime sleepiness predicted internalizing problems as rated by the teacher in children in the ANX group. No association was found between the sleep problems and teacher ratings of internalizing or externalizing problems in children in the ADHD or the ANX+ADHD groups, or between the sleep problems and teacher ratings of externalizing problems for any group of children.<br> The persistence rate from T1 to T2 of having sleep problems in a clinical range (total CSHQ score above 41) was 72.4% in the group of referred children. The persistence rates of having a total sleep problem in a clinical range did not differ significantly between children in the ANX group (76.0%), the ADHD group (70.6%), or in the ANX+ADHD group (68.8%). Persistence rates for types of sleep problems varied from 56.3% (bedtime resistance problems) to 86.0% (parasomnias) in the group of referred children. The total CSHQ score at T1 significantly predicted the CSHQ score at T2 in the group of referred children.<br> Conclusion: The results demonstrate a high frequency of sleep problems as reported by the mother in a clinical sample children with anxiety disorders and/or ADHD. Children with anxiety disorders have more sleep problems than children with ADHD. The sleep problems are associated with impairments in attentional function for both referred and nonreferred children, and with more internalizing problems reported by the teacher in the subgroup of children with anxiety disorders and no comorbid ADHD. The sleep problems are persistent in the majority of children in the clinical sample. Clinicians in child and adolescent mental health service (CAMHS) need to be aware of sleep problems and include assessment and targeted intervention towards sleep problems when treating children with anxiety disorders and/or ADHD.