Heartbeat evoked potentials during sleep and daytime behavior in children with sleep disordered breathing

Abstract

Rationale: Event-related brain potentials (ERP) allow probing of cortical information processing, but when evoked with externally induced stimuli may disrupt sleep homeostasis and do not elucidate insight into intrinsic cortical information processing. To investigate if cortical processing of intrinsic information in children with sleep disordered breathing (SDB) is different from healthy children and if so, whether it resolves with treatment, we utilized heartbeat as a source of interoceptive ERP. Objective: To investigate heartbeat evoked potentials (HEP) during sleep in healthy children and in children with SDB before and after treatment and to explore if there are any associations between HEP and daytime behavioral deficits in children with SDB. Methods: Heartbeat-aligned EEG was assessed for presence of HEP within stage 2, SWS and REM sleep in forty children with primarily mild to moderate SDB before and after adenotonsillectomy, and in 40 matched controls at similar time points. Measurements and Results: In both groups, non-random HEP were present in all sleep stages analyzed; however amplitude of HEP were significantly lower in children with SDB during NREM sleep (stage 2: p = 0.03; SWS: p = 0.001). This between-group difference was not significant post-adenotonsillectomy. Significant negative associations between HEP and daytime behavioral scores were observed at baseline. Conclusion: Children with SDB displayed reduced HEP amplitude during sleep, which might be indicative of changes in afferent sensory inputs to the brain and/ or signify differences in sensory gating of cardiac-related information in the insular cortex. Adenotonsillectomy appears to reverse this effect.