Purpose: The aim of this study was to assess risk factors for excessive autonomic activation during sleep (EAAS) and its association with sleep problems, impaired behavior, and poor academic performance in primary school children.
Methods: Data from a community-based study on 997 primary school children were used. Based on nocturnal home pulse oximetry, autonomic activation during sleep was defined as a pulse rate increase by more than 20%. Children with ≥35.9 autonomic activations per hour (i.e., ≥ the 95(th) centile) were classified as suffering from EAAS and compared with controls. Sleep problems, impaired behavior, and academic performance were assessed by parental questionnaires and analysis of school reports.
Results: According to the above-mentioned definition, EAAS was diagnosed in 52 children (67% male). Risk factors for EAAS were male gender (odds ratio [95% confidence interval]: 2.06 [1.14-3.72]) and presence of symptoms of sleep-disordered breathing (3.48 [1.29-9.43]). Children with EAAS had a higher prevalence of hyperactive behavior (39.2% vs. 26.0%; p = 0.05) and enuresis (5.8% vs. 0.8%; p = 0.017) but not of poor academic performance. The association with hyperactive behavior was confirmed in a subsample (n = 119) using the Strengths and Difficulties Questionnaire. Mean (SD) score of the hyperactive-inattentive scale was 4.5 (2.8) for EAAS and 3.4 (2.7) for non-EAAS (p = 0.04).
Conclusion: EAAS may be a marker of sleep disruption in children and may predict the occurrence of enuresis and hyperactive behavior.