Joel Traylor

Direct comparison of two new actigraphs and polysomnography in children and adolescents.

STUDY OBJECTIVES To evaluate the validity and reliability of 2 new models of commercially available actigraphs compared to polysomnography for children and adolescents. DESIGN AND SETTING Subjects concurrently wore the Ambulatory Monitoring Inc. Motionlogger Sleep Watch (AMI) and the Phillips Respironics Mini-Mitter Actiwatch-2 (PRMM) while undergoing overnight polysomnography (PSG) in a pediatric sleep laboratory housed in a tertiary care childrens hospital. PARTICIPANTS 115 youth (59 girls, 56 boys), ages 3-18 years (mean 8.8 years, SD 4.4 years). MEASUREMENTS Outcome variables were total sleep time (TST), wake after sleep onset (WASO), and sleep efficiency (SE). Epoch-by-epoch comparisons were made between the 2 devices and PSG to determine sensitivity, specificity, and accuracy. Agreement between the 2 devices was determined with t-tests and the Bland-Altman concordance technique. Different algorithms/sensitivities, developmental age groups, and sleep disordered breathing (SDB) status were also examined. RESULTS For both device brands, sensitivity (0.89-0.97), specificity (0.54-0.77), and accuracy (0.87-0.90) were similar to previous reports. Notably, compared to PSG, both device brands significantly overestimated WASO, while the AMI device also significantly underestimated TST. Inter-device comparison of the 2 brands found poor agreement for TST, WASO, and SE. Agreement with PSG differed depending on the scoring algorithm (AMI) or sensitivity setting (PRMM), as well as across developmental age group and sleep disordered breathing (SDB) status. CONCLUSIONS Similar to previous reports, both new actigraph brands were found to have good sensitivity (to detect sleep), but poorer specificity (to detect wake). Study results also suggest that researchers should adjust the scoring algorithm/sensitivity depending on a studys design (e.g., young children vs. adolescents, healthy children vs. youth with SDB). Further, inter-device reliability was poor, suggesting the need for caution when comparing results across studies that use different brands of actigraphic devices.

Effects of Positive Airway Pressure Therapy on Neurobehavioral Outcomes in Children with Obstructive Sleep Apnea

RATIONALE Positive airway pressure therapy is frequently used to treat obstructive sleep apnea in children. However, it is not known whether positive airway pressure therapy results in improvements in the neurobehavioral abnormalities associated with childhood sleep apnea. OBJECTIVES We hypothesized that positive airway pressure therapy would be associated with improvements in attention, sleepiness, behavior, and quality of life, and that changes would be associated with therapy adherence. METHODS Neurobehavioral assessments were performed at baseline and after 3 months of positive airway pressure therapy in a heterogeneous group of 52 children and adolescents. MEASUREMENTS AND MAIN RESULTS Adherence varied widely (mean use, 170 ± 145 [SD] minutes per night). Positive airway pressure therapy was associated with significant improvements in attention deficits (P < 0.001); sleepiness on the Epworth Sleepiness Scale (P < 0.001); behavior (P < 0.001); and caregiver- (P = 0.005) and child- (P < 0.001) reported quality of life. There was a significant correlation between the decrease in Epworth Sleepiness Scale at 3 months and adherence (r = 0.411; P = 0.006), but not between other behavioral outcomes and adherence. Behavioral factors also improved in the subset of children with developmental delays. CONCLUSIONS These results indicate that, despite suboptimal adherence use, there was significant improvement in neurobehavioral function in children after 3 months of positive airway pressure therapy, even in developmentally delayed children. The implications for improved family, social, and school function are substantial. Clinical trial registered with www.clinicaltrials.gov (NCT 00458406).

Long-Term Effects of Caffeine Therapy for Apnea of Prematurity on Sleep at School Age

RATIONALE Apnea of prematurity is a common condition that is usually treated with caffeine, an adenosine receptor blocker that has powerful influences on the central nervous system. However, little is known about the long-term effects of caffeine on sleep in the developing brain. OBJECTIVES We hypothesized that neonatal caffeine use resulted in long-term abnormalities in sleep architecture and breathing during sleep. METHODS A total of 201 ex-preterm children aged 5-12 years who participated as neonates in a double-blind, randomized, controlled clinical trial of caffeine versus placebo underwent actigraphy, polysomnography, and parental sleep questionnaires. Coprimary outcomes were total sleep time on actigraphy and apnea-hypopnea index on polysomnography. MEASUREMENTS AND MAIN RESULTS There were no significant differences in primary outcomes between the caffeine group and the placebo (adjusted mean difference of -6.7 [95% confidence interval (CI) = -15.3 to 2.0 min]; P = 0.13 for actigraphic total sleep time; and adjusted rate ratio [caffeine/placebo] for apnea-hypopnea index of 0.89 [95% CI = 0.55-1.43]; P = 0.63). Polysomnographic total recording time and total sleep time were longer in the caffeine group, but there was no difference in sleep efficiency between groups. The percentage of children with obstructive sleep apnea (8.2% of caffeine group versus 11.0% of placebo; P = 0.22) or elevated periodic limb movements of sleep (17.5% in caffeine group versus 11% in placebo group) was high, but did not differ significantly between groups. CONCLUSIONS Therapeutic neonatal caffeine administration has no long-term effects on sleep duration or sleep apnea during childhood. Ex-preterm infants, regardless of caffeine status, are at risk for obstructive sleep apnea and periodic limb movements in later childhood.

Randomized, double-blind clinical trial of two different modes of positive airway pressure therapy on adherence and efficacy in children.

STUDY OBJECTIVES To determine the effects of bilevel positive airway pressure with pressure release technology (Bi-Flex) on adherence and efficacy in children and adolescents compared to standard continuous positive airway pressure (CPAP) therapy. We hypothesized that Bi-Flex would result in improved adherence but similar efficacy to CPAP. METHODS This was a randomized, double-blinded clinical trial. Patients with obstructive sleep apnea were randomized to CPAP or Bi-Flex. Repeat polysomnography was performed on pressure at 3 months. Objective adherence data were obtained at 1 and 3 months. RESULTS 56 children and adolescents were evaluated. There were no significant differences in the number of nights the device was turned on, or the mean number of minutes used at pressure per night for CPAP vs Bi-Flex (24 ± 6 vs 22 ± 9 nights, and 201 ± 135 vs 185 ± 165 min, respectively, for Month 1). The apnea hypopnea index decreased significantly from 22 ± 21/h to 2 ± 3/h on CPAP (p = 0.005), and 18 ± 15/h to 2 ± 2/h on Bi-Flex (p < 0.0005), but there was no significant difference between groups (p = 0.82 for CPAP vs Bi-Flex). The Epworth Sleepiness Scale decreased from 8 ± 5 to 6 ± 3 on CPAP (p = 0.14), and 10 ± 6 to 5 ± 5 on Bi-Flex (p < 0.0005; p = 0.12 for CPAP vs Bi-Flex). CONCLUSIONS Both CPAP and Bi-Flex are efficacious in treating children and adolescents with OSAS. However, adherence is suboptimal with both methods. Further research is required to determine ways to improve adherence in the pediatric population.

Predictors of positive airway pressure therapy adherence in children: a prospective study.

STUDY OBJECTIVES Children with obstructive sleep apnea are increasingly being treated with positive airway pressure (PAP), particularly if they have underlying medical conditions. Although PAP is an effective treatment, its use is challenging due to poor adherence. We hypothesized that demographic, psychosocial, and polysomnographic parameters would be related to PAP adherence. We therefore prospectively collected data potentially pertaining to PAP adherence, and correlated it with PAP use. METHODS Fifty-six patients and their parents completed a series of psychosocial questionnaires prior to PAP initiation. Objective adherence data were obtained after 1 and 3 months of PAP use. RESULTS The population was primarily obese; 23% had neurodevelopmental disabilities. PAP adherence varied widely, with PAP being worn 22 ± 8 nights in month-1, but mean use was only 3 ± 3 h/night. The greatest predictor of use was maternal education (p = 0.002 for nights used; p = 0.033 for mean h used/night). Adherence was lower in African American children vs other races (p = 0.021). In the typically developing subgroup, adherence correlated inversely with age. Adherence did not correlate with severity of apnea, pressure levels, or psychosocial parameters other than a correlation between family social support and nights of PAP use in month-3. CONCLUSIONS PAP adherence in children and adolescents is related primarily to family and demographic factors rather than severity of apnea or measures of psychosocial functioning. Further research is needed to determine the relative contributions of maternal education, socioeconomic status and cultural beliefs to PAP adherence in children, in order to develop better adherence programs.

Predictors of Perioperative Complications in Higher Risk Children after Adenotonsillectomy for Obstructive Sleep Apnea: A Prospective Study

Objective Retrospective studies have limitations in predicting perioperative risk following adenotonsillectomy in children with obstructive sleep apnea syndrome (OSAS). Few prospective studies exist. We hypothesized that demographic and polysomnographic (PSG) variables would predict respiratory and general perioperative complications. Study Design Prospective, observational cohort study. Setting Pediatric tertiary center. Subjects and Methods Consecutive children undergoing adenotonsillectomy for OSAS within 12 months of PSG were evaluated for complications occurring within 2 weeks of surgery. Results There were 329 subjects, with 27% <3 years old, 24% obese, 16% preterm, and 29% with comorbidities. In this higher risk population, 28% had respiratory complications (major and/or minor), and 33% had nonrespiratory complications. Significant associations were found between PSG parameters and respiratory complications as follows: apnea hypopnea index (rank-biserial correlation coefficient [r] = 0.174, P = .017), SpO2 nadir (r = −0.332, P < .0005), sleep time with SpO2 <90% (r = 0.298, P < .0005), peak end-tidal CO2 (r = 0.354, P < .0005), and sleep time with end-tidal CO2 >50 mm Hg (r = 0.199, P = .006). Associations were also found between respiratory complications and age <3 years (r = −0.174, P = .003) or black race (r = 0.123, P = .039). No significant associations existed between PSG parameters and nonrespiratory complications. A model using age <3 years, SpO2 nadir, and peak CO2 predicted respiratory complications better than the American Academy of Pediatrics or American Academy of Otolaryngology—Head and Neck Surgery Foundation guidelines but was imperfect (area under the curve = 0.72). Conclusion Thus, PSG predicted perioperative respiratory, but not nonrespiratory, complications in children with OSAS. Age <3 years or black race are high-risk factors. Present guidelines have limitations in determining the need for postoperative admission.

Feasibility of comprehensive, unattended ambulatory polysomnography in school-aged children.

STUDY OBJECTIVES Although unattended ambulatory polysomnography (PSG) is frequently performed in adults, few studies have been performed in children. The objective of this study was to evaluate the feasibility of comprehensive, ambulatory PSG, including electroencephalography, in school-aged children in the home environment. METHODS A total of 201 children, born premature with birth weights of 500-1,250 grams, currently aged 5-12 years and living in Canada and Australia, underwent unattended ambulatory PSG. RESULTS PSG was initially technically satisfactory in 183 (91%) cases. Fourteen studies were satisfactory when repeated, resulting in an overall satisfactory rate of 197 (98%). Artifact-free signals were obtained for ≥ 75% of recording time in more than 92% of subjects, with the exception of nasal pressure, which was satisfactory for ≥ 75% of recording time in only 67% of subjects. However, thermistry signals were satisfactory for ≥ 75% of recording time in 92% of subjects, and some measure of airflow was present for ≥ 75% of recording time in 96% of subjects. Children slept very well, with a long total sleep time (534 ± 73 [mean ± SD] minutes), high sleep efficiency (92% ± 5%), and low arousal index (9 ± 3/h). Parents and children reported a high rate of satisfaction with the study. CONCLUSIONS This large, international study has shown that comprehensive, unattended, ambulatory PSG is feasible, technically adequate and well-tolerated in school-aged children when performed under research conditions. Further studies regarding the cost efficacy of this approach, and generalizability of the findings to a clinical population, are warranted.

Nocturnal saturation and glucose tolerance in children with cystic fibrosis.

Background Glucose intolerance is common in cystic fibrosis (CF), and is associated with worsening pulmonary function and nutritional status, and increased mortality. As sleep-disordered breathing is associated with disorders of glucose metabolism, it was hypothesised that recurrent episodes of hypoxaemia during sleep, and sleep disruption, would be associated with inflammation and glucose intolerance in CF. Methods 25 children (aged 14±4 (mean±SD) years) with CF underwent polysomnography, actigraphy, measurement of serum inflammatory markers and oral glucose tolerance testing. Blood glucose area under the curve (AUC), as a cumulative measure of glucose response, was determined. Polysomnography data were compared with retrospective data from 25 healthy controls. Results Forced expiratory volume in 1 s was 92±14% predicted. 24 subjects underwent glucose tolerance testing, of whom 29% had impaired glucose tolerance and 4% had diabetes. The mean nocturnal oxygen saturation correlated negatively with glucose AUC at 120 min (r=−0.49, p=0.015). Partial correlations and regression models including age, body mass index, nocturnal saturation and pulmonary function indicated that nocturnal saturation accounted for the majority of the predictive power for glucose AUC (R2=0.24, p=0.001). There were no meaningful relationships between sleep quality, inflammation and glucose tolerance. Conclusions Lower oxyhaemoglobin saturation is associated with worse glucose regulation in children with CF. Further studies are needed to determine whether lower saturation negatively impacts glucose regulation or, alternatively, whether abnormalities in glucose metabolism are an early sign of pulmonary dysfunction.

Perinatal Risk Factors Associated with the Obstructive Sleep Apnea Syndrome in School-Aged Children Born Preterm.

STUDY OBJECTIVES The obstructive sleep apnea syndrome (OSAS) is more prevalent in ex-preterm children compared to the general pediatric population. However, it is unknown whether OSAS in ex-preterm children is associated with specific perinatal risk factors. This multicenter cohort study aimed to determine perinatal factors associated with OSAS at school age. METHODS 197 ex-preterm (500-1,250 g) children aged 5-12 y who participated as neonates in a double-blind, randomized clinical trial of caffeine versus placebo (Caffeine for Apnea of Prematurity) underwent comprehensive ambulatory polysomnography. A negative binomial regression model was used to identify perinatal risk factors associated with OSAS. RESULTS 19 children had OSAS (9.6%). Chorioamnionitis and multiple gestation were positively associated with OSAS with P values of 0.014 and 0.03, respectively. Maternal white race (P = 0.047) and maternal age (P = 0.002) were negatively associated with OSAS. Other risk factors, such as birth weight, Apgar score at 5 min, antenatal corticosteroids, delivery route, and sex were not significant. CONCLUSIONS OSAS is very frequent, and is associated with chorioamnionitis and multiple gestation in ex-preterm children. Those born to older white mothers appear to be protected. We speculate that the former may be due to systemic inflammation and the latter to a higher socio-economic status. COMMENTARY A commentary on this article appears in this issue on page 721.

Rapid Eye Movement Latency in Children and Adolescents

Rapid eye movement sleep distribution changes during development, but little is known about rapid eye movement latency variation in childhood by age, sex, or pathologic sleep states. We hypothesized that: (1) rapid eye movement latency would differ in normal children by age, with a younger cohort (1-10 years) demonstrating shorter rapid eye movement latency than an older group (>10-18 years); (2) rapid eye movement latency in children would differ from typical adult rapid eye movement latency; and (3) intrinsic sleep disorders (narcolepsy, pediatric obstructive sleep apnea syndrome) would disrupt normal developmental patterns of rapid eye movement latency. A retrospective chart review included data from clinic visits and of rapid eye movement latency and other parameters measured by overnight polysomnography. Participants included 98 control children, 90 children with obstructive sleep apnea syndrome, and 13 children with narcolepsy. There were no statistically significant main effects of age category or sex on rapid eye movement latency. Rapid eye movement latency, however, exhibited a significant inverse correlation with age within the older control children. Healthy children exhibited rapid eye movement latencies significantly longer than adults. Normal control patients demonstrated significantly longer rapid eye movement latency than obstructive sleep apnea syndrome and narcolepsy patients.