Longitudinal Impact of Resolution of Snoring in Young Children on Psychosocial Functioning.

OBJECTIVE: To determine whether sustained resolution of sleep disordered breathing (SDB) in young children, either because of treatment or spontaneous recovery, predicted long-term improvements in quality of life, family functioning, and parental stress. STUDY DESIGN: Children diagnosed with primary snoring (n = 16), mild obstructive sleep apnea (OSA, n = 11), moderate-severe (MS) OSA (n = 8), and healthy nonsnoring controls (n = 25) at ages 3-5 years underwent repeat polysomnography at 6-8 years. Parents completed quality of life and parental stress questionnaires at both time points. Resolution of SDB was determined as obstructive apnea hypopnea index (OAHI) ≤1 event/hour, or absence of snoring during polysomnography or on parent report. Linear mixed-model analyses determined the effects of resolution on psychosocial morbidity. OAHI was used to determine the predictive value of changes in SDB severity on psychosocial outcomes. RESULTS: Fifty percent of primary snoring, 45% mild OSA, and 63% MS OSA resolved, of which 67% received treatment. Children originally diagnosed with SDB continued to show significant psychosocial impairments compared with nonsnoring controls, irrespective of resolution. A reduction in OAHI predicted improvements in physical symptoms, school functioning, family worry and family relationships, and stress related to a difficult child. CONCLUSIONS: Treatment was more likely to result in resolution of SDB if original symptoms were MS. Children originally diagnosed with SDB, irrespective of resolution, continued to experience psychosocial dysfunction suggesting additional interventions are required.

Review of disrupted sleep patterns in Smith-Magenis syndrome and normal melatonin secretion in a patient with an atypical interstitial 17p11.2 deletion.

Smith-Magenis syndrome (SMS) is a disorder characterized by multiple congenital anomalies and behavior problems, including abnormal sleep patterns. It is most commonly due to a 3.5 Mb interstitial deletion of chromosome 17 band p11.2. Secretion of melatonin, a hormone produced by the pineal gland, is the body's signal for nighttime darkness. Published reports of 24-hr melatonin secretion patterns in two independent SMS cohorts (US and France) document an inverted endogenous melatonin pattern in virtually all cases (96%), suggesting that this finding is pathognomic for the syndrome. We report on a woman with SMS due to an atypical large proximal deletion ( approximately 6Mb; cen<->TNFRSFproteinB) of chromosome band (17)(p11.2p11.2) who presents with typical sleep disturbances but a normal pattern of melatonin secretion. We further describe a melatonin light suppression test in this patient. This is the second reported patient with a normal endogenous melatonin rhythm in SMS associated with an atypical large deletion. These two patients are significant because they suggest that the sleep disturbances in SMS cannot be solely attributed to the abnormal diurnal melatonin secretion versus the normal nocturnal pattern.

Melatonin entrains free-running blind people according to a physiological dose-response curve.

The specific circadian role proposed for endogenous melatonin production was based on a study of sighted people who took low pharmacological doses (500 microg) of this chemical signal for the "biological night": the magnitude and direction of the induced phase shifts were dependent on what time of day exogenous melatonin was administered and were described by a phase-response curve that turned out to be the opposite of that for light. We now report that lower (physiological) doses of up to 300 microg can entrain (synchronize) free-running circadian rhythms of 10 totally blind subjects that would otherwise drift later each day. The resulting log-linear dose-response curve in the physiological range adds support for a circadian function of endogenous melatonin in humans. Efficacy of exogenous doses in the physiological range are of clinical significance for totally blind people who will need to take melatonin daily over their entire lifetimes in order to remain entrained to the 24 h day. Left untreated, their free-running endocrine, metabolic, behavioral, and sleep/wake cycles can be almost as burdensome as not having vision.

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

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.

Sleep disordered breathing in early childhood: quality of life for children and families.

OBJECTIVES: To characterize health-related quality of life (QOL) in preschool children with sleep disordered breathing (SDB) and their families compared with nonsnoring control patients in the community. It was hypothesized that children with SDB and their families would have poorer QOL than control children, that a relationship would be found between SDB severity and QOL, and that even children with mild SDB and their families would have reduced QOL. PARTICIPANTS AND METHODS: A clinical sample of preschool children (3-5 y) with SDB diagnosed by gold standard polysomnography (primary snoring, PS = 56, mild obstructive sleep apnea, OSA = 35, moderate/severe OSA = 24) and control children recruited from the community (n = 38) were studied. Parents completed health-related QOL and parenting stress questionnaires. RESULTS: Children and families in the PS and mild OSA groups had consistently poorer QOL than control children (both P < 0.05-0.001), based on parent ratings, and parents of children with PS had elevated stress ratings relative to control children (P < 0.05-0.001). The moderate/severe OSA group differed from the control group on select measures of parent and family QOL (worry, P < 0.001 and total family impact, P < 0.05). CONCLUSIONS: Our findings demonstrate that sleep disordered breathing is associated with reduced quality of life in preschool children and their families. These results support previous quality of life findings in older children and in samples with broader age ranges. Furthermore, clinically referred preschool children with mild forms of sleep disordered breathing may be at greatest risk.

Sleep-disordered breathing in preschool children is associated with behavioral, but not cognitive, impairments.

BACKGROUND: Sleep-disordered breathing (SDB) has been associated with impaired cognitive and behavioral function in school children; however, there have been limited studies in preschool children when the incidence of the disorder peaks. Thus, the aim of this study was to compare cognitive and behavioral functions of preschool children with SDB to those of non-snoring control children. METHODS: A clinical sample of 3-5 year-old children (primary snoring [PS], n=60; mild obstructive sleep apnea syndrome [OSAS], n=32; moderate/severe [MS] OSAS, n=24) and a community sample of non-snoring control children (n=37) were studied with overnight polysomnography. Cognitive performance and behavioral information were collected. RESULTS: Children with PS and mild OSAS had poorer behavior than controls on numerous measures (p<.05-p<.001), and on some measures they had poorer behavior than the MS OSAS group (p<.05). In contrast, all groups performed similarly on cognitive assessment. Outcomes related more to sleep than respiratory measures. CONCLUSIONS: SDB of any severity was associated with poorer behavior but not cognitive performance. The lack of significant cognitive impairment in this age group may have identified a "window of opportunity" where early treatment may prevent deficits arising later in childhood.

Time course of EEG slow-wave activity in pre-school children with sleep disordered breathing: a possible mechanism for daytime deficits?

BACKGROUND: Daytime deficits in children with sleep disordered breathing (SDB) are theorized to result from hypoxic insult to the developing brain or fragmented sleep. Yet, these do not explain why deficits occur in primary snorers (PS). The time course of slow wave EEG activity (SWA), a proxy of homeostatic regulation and cortical maturation, may provide insight. METHODS: Clinical and control subjects (N=175: mean age 4.3±0.9 y: 61% male) participated in overnight polysomnography (PSG). Standard sleep scoring and power spectral analyses were conducted on EEG (C4/A1; 0.5-<3.9Hz). Univariate ANOVA's evaluated group differences in sleep stages and respiratory parameters. Repeated-measures ANCOVA evaluated group differences in the time course of SWA. RESULTS: Four groups were classified: controls (OAHI ≤ 1 event/h; no clinical history); PS (OAHI ≤ 1 event/h; clinical history); mild OSA (OAHI=1-5 events/h); and moderate to severe OSA (MS OSA: OAHI>5 events/h). Group differences were found in the percentage of time spent in NREM Stages 1 and 4 (p<0.001) and in the time course of SWA. PS and Mild OSA children had higher SWA in the first NREM period than controls (p<0.05). All SDB groups had higher SWA in the fourth NREM period (p<0.01). CONCLUSIONS: These results suggest enhanced sleep pressure but impaired restorative sleep function in pre-school children with SDB, providing new insights into the possible mechanism for daytime deficits observed in all severities of SDB.

Working memory in children with sleep-disordered breathing: objective versus subjective measures.

BACKGROUND: Parents consistently report working memory deficits in children with sleep-disordered breathing (SDB); however, results from objective testing measures are inconsistent. This study aims to examine and compare working memory performance in children with various degrees of severity of SDB using both parent report and objective testing. METHODS: Subjects included 127 children aged 7-12 years (mean age 9.6 ± 1.6 y: 71 M/56 F). Overnight polysomnography classified subjects into four groups: control (N=34); primary snoring (PS: N=55), mild obstructive sleep apnoea (mild OSA: N=22) and moderate to severe OSA (MS OSA: N=16). The Behaviour Rating Inventory of Executive Function (BRIEF) was used as the parent reported measure of working memory. A computerised task involving immediate recognition of playing cards (CogHealth) was used as the objective measure. RESULTS: Results of the BRIEF revealed working memory deficits at all severities of SDB compared to controls. Results of CogHealth revealed no difference between SDB groups and controls; however, mild OSA performed significantly worse than PS. Comparison of the two measures revealed that parents of controls reported less deficits, and parents of PS reported more deficits, than were found on the objective measure of working memory. CONCLUSIONS: This study showed that parents of children with less severe SDB have a tendency to overestimate the level of working memory deficit in their children, possibly as a reflection of behaviour. This suggests that observation of deficits in working memory may be largely dependent on the assessment method and children with SDB may not be as impaired as previously thought.

Neurobehavioral function is impaired in children with all severities of sleep disordered breathing.

OBJECTIVE: Sleep disordered breathing (SDB) is common in children and ranges in severity from primary snoring (PS), to obstructive sleep apnea syndrome (OSAS). This study investigated everyday function (behavior, attention, executive skills) in children with varying degrees of SDB and control children with no history of SDB recruited from the community. METHODS: One hundred thirty-six children aged 7-12 were studied. Routine overnight polysomnography (PSG) classified children into 4 groups: PS (n=59), mild OSAS (n=24), moderate/severe OSAS (n=18), and controls (n=35). Behavioral function and behavioral aspects of attention and executive function were assessed using the Child Behavior Checklist (CBCL) and the Behavior Rating Inventory of Executive Function (BRIEF). RESULTS: Children with all severities of SDB had significantly higher rates of total, internalizing and externalizing behavioral problems compared to control children. Increased rates of behavioral executive dysfunction were also found across the SDB spectrum. CONCLUSION: Our findings suggest that behavioral, attention, and executive function difficulties are present in children with PS as well as OSAS. These results have implications for the treatment of milder forms of SDB, particularly PS, which is commonly viewed as benign.

Cognitive and academic functions are impaired in children with all severities of sleep-disordered breathing.

STUDY OBJECTIVE: The impact of the broad spectrum of SDB severity on cognition in childhood has not been well studied. This study investigated cognitive function in children with varying severities of SDB and control children with no history of SDB. METHODS: One hundred thirty-seven children (75 M) aged 7-12 were studied. Overnight polysomnography (PSG) classified children into four groups: primary snoring (PS) (n = 59), mild obstructive sleep apnea syndrome (OSAS) (n = 24), moderate/severe OSAS (n = 19), and controls (n = 35). Cognition was measured with a short battery of psychological tests including the Wechsler Abbreviated Scale of Intelligence (WASI), the Wide Range Achievement Test-3rd Edition (WRAT-3), the Rey Complex Figure Test (RCFT) and the Controlled Oral Word Association Test (COWAT). RESULTS: There was lower general intellectual ability in all children with SDB regardless of severity. Higher rates of impairment were also noted on measures of executive and academic functioning in children with SDB. CONCLUSIONS: Our findings suggest that neurocognitive deficits are common in children with SDB regardless of disease severity, highlighting that such difficulties may be present in children in the community who snore but are otherwise healthy; thus our results have important implications for the treatment of pediatric SDB.