Long-Term Cognitive and Behavioral Outcomes following Resolution of Sleep Disordered Breathing in Preschool Children

Abstract

This study aimed to determine the long term effects of resolution of SDB in preschool children, either following treatment or spontaneous recovery, on cognition and behavior. Children diagnosed with SDB at 3-5y (N = 35) and non-snoring controls (N = 25), underwent repeat polysomnography (PSG) and cognitive and behavioral assessment 3 years following a baseline study. At follow-up, children with SDB were grouped into Resolved and Unresolved. Resolution was defined as: obstructive apnea hypopnea index (OAHI) ≤1 event/h; no snoring detected on PSG; and no parental report of habitual snoring. 57% (20/35) of children with SDB received treatment, with SDB resolving in 60% (12/20). 43% (15/35) were untreated, of whom 40% (6/15) had spontaneous resolution of SDB. Cognitive reduced between baseline and follow-up, however this was not related to persistent disease, with no difference in cognitive outcomes between Resolved, Unresolved or Control groups. Behavioral functioning remained significantly worse in children originally diagnosed with SDB compared to control children, regardless of resolution. Change in OAHI did not predict cognitive or behavioral outcomes, however a reduction in nocturnal arousals, irrespective of full resolution, was associated with improvement in attention and aggressive behavior. These results suggest that resolution of SDB in preschool children has little effect on cognitive or behavioral outcomes over the long term. The association between sleep fragmentation and behavior appears independent of SDB, however may be moderated by concomitant SDB. This challenges the assumption that treatment of SDB will ameliorate associated cognitive and behavioural deficits and supports the possibility of a SDB phenotype.

Fig 1. Profile of SDB cohort at baseline and follow-up.

At follow-up 16 children originally diagnosed with PS, 11 with Mild OSA and 8 with MS OSA returned. Of these, 18 had resolved and 17 had ongoing SDB. Twelve children who had resolved received treatment. Eight children who were unresolved also received treatment.

Fig 2. Mean scores on Stanford-Binet (2A) and NEPSY (2B) at baseline (black bars) and follow-up (white bars) for the Control, Resolved and Unresolved groups.

The dotted line represents the population mean.

Fig 3. Mean domain scores on CBCL (3A) and BRIEF (3B) at baseline (black bars) and follow-up (white bars) for the Control, Resolved and Unresolved groups.

The dotted line represents the population mean. The solid lines represent the between group differences. *p<0.05, **p<0.01, ***p<0.001.