Behavioral and emotional characteristics of Canadian children with obesity and moderate-severe sleep-disordered breathing treated with positive airway pressure: longitudinal changes and associations with adherence.

STUDY OBJECTIVES: Behavioral characteristics and outcomes of positive airway pressure (PAP) therapy in children with obesity and moderate-severe sleep-disordered breathing (SDB) have not been reported. Our aims were to 1) determine baseline behavioral/emotional symptoms of this population and characterize changes over time with PAP, and 2) examine associations between baseline behavioral/emotional symptoms and PAP adherence. METHODS: This multicenter prospective cohort study of children with obesity prescribed PAP for moderate-severe SDB assessed PAP adherence (≥ 4 h/night, >50% of nights, usage diaries, downloads) and compared behavioral/emotional characteristics with parent- and child-reported Conners Rating Scale (Conners) and the Child Behavior Checklist (CBCL) at baseline and 1 year after PAP prescription between adherent and nonadherent participants; scores at baseline were compared retrospectively between adherence groups. RESULTS: Twenty-four children were included (median 14.1 years [IQR:12.4,16.0]; 87.5% males). Baseline Conners and CBCL scores were elevated (parent- and child-reported Conners inattention and hyperactivity subscales and CBCL subscales [total, internalizing, externalizing]). Baseline parent-reported Conners scores were significantly more elevated in the nonadherent than adherent group (inattention: 73.3 ± 8.5 vs 60.5 ± 14.6, P = .01; hyperactivity: 70.9 ± 11.1 vs 59.1 ± 16.0, P = .05). This difference was present 1 year later for inattention (P = .01) but not for hyperactivity (P = .09). Parent-reported CBCL scores improved over 1 year in adherent but not nonadherent participants. CONCLUSIONS: We found that children with obesity and moderate-severe SDB have elevated symptoms of behavioral/emotional concerns on standardized testing. Parent-reported emotional characteristics improved in the adherent but not in the nonadherent group. Children with greater inattention/hyperactivity at baseline were less adherent to PAP, suggesting this may contribute to PAP nonadherence. CITATION: Constantin E, MacLean JE, Barrowman N, et al. Behavioral and emotional characteristics of Canadian children with obesity and moderate-severe sleep-disordered breathing treated with positive airway pressure: longitudinal changes and associations with adherence. J Clin Sleep Med. 2023;19(3):555-562.

Effect of Play2Sleep on mother-reported and father-reported infant sleep: a sequential explanatory mixed-methods study of a randomized controlled trial.

STUDY OBJECTIVES: This study evaluated the effect on infant sleep of a novel intervention (Play2Sleep) that combined infant sleep information with self-modeled video feedback on parent-infant interactions. METHODS: An explanatory sequential mixed-methods design consisting of a randomized controlled trial with 63 mother-father-infant triads randomized to Play2Sleep or comparison home visit interventions was used. We used repeated measures analysis of covariance to detect changes in infant night wakings, nocturnal wakefulness, and sleep durations and Wilcoxon signed rank test to evaluate changes in perception of infant sleep problems. Family interviews (n = 20) were used to explain the quantitative findings and analyzed qualitatively using thematic analysis. RESULTS: Play2Sleep was effective in reducing maternal-reported infant wakefulness, F(1,55) = 5.33, P = .03, partial η2 = .09, and the number of paternal-reported naps, F(1,58) = 4.90, P = .03, partial η2 = .08. Parents in the Play2Sleep group reported significant improvements in problematic infant sleep that were not observed in the comparison group; however, Play2Sleep was not effective in reducing the number of parent-reported night wakings. Information overwhelm, learning infant cues, and working together with a subtheme of father involvement were key qualitative themes developed to explain the quantitative results. Unplanned exploratory analyses revealed a significant improvement in maternal depression symptoms in the Play2Sleep group. CONCLUSIONS: This study suggests Play2Sleep could improve infant sleep by promoting parental awareness of infant cues and father involvement and improving maternal depression. Additional research is needed to determine the optimal number and timing of sessions. CLINICAL TRIAL REGISTRATION: Registry: ClinicalTrials.gov; Name: Play2Sleep: Using Play to Improve Sleep; URL: https://clinicaltrials.gov/ct2/show/NCT02742155; Identifier: NCT02742155. CITATION: Keys EM, Benzies KM, Kirk VG, Duffett-Leger L. Effect of Play2Sleep on mother-reported and father-reported infant sleep: a sequential explanatory mixed-methods study of a randomized controlled trial. J Clin Sleep Med. 2022;18(2):439-452.

Cardiovascular changes in children with obstructive sleep apnea and obesity after treatment with noninvasive ventilation.

STUDY OBJECTIVES: Adults with obesity and obstructive sleep apnea (OSA) are at risk for cardiometabolic disease, and this risk likely extends to children with both conditions. Noninvasive ventilation (NIV; including continuous and bilevel positive airway pressure) is often used to treat OSA in children with obesity. The aim of this study was to examine the impact of NIV treatment on heart rate variability (HRV), as a marker of cardiovascular risk, in children with obesity and newly diagnosed OSA. METHODS: A prospective multicenter cohort study was conducted in children with obesity prescribed NIV therapy for newly diagnosed moderate-severe OSA. Measurements of HRV were derived from polysomnography recordings at baseline and after 12 months of treatment. HRV parameters were examined by sleep stage, before and after arousal and oxygen desaturation events. HRV parameters were compared between time points using pair t tests as well as mixed model analysis. RESULTS: Twelve children had appropriate data for analysis at baseline and 12 months. Heart rate decreased by 4.5 beats/min after NIV treatment, with no change in HRV parameters. HRV parameters differed by sleep stage and showed an increase in arousal-related sympathetic-parasympathetic balance after 12 months of NIV treatment. HRV parameters did not differ before and after oxygen desaturation events. CONCLUSIONS: NIV for the treatment in children with obesity and OSA resulted in a small decrease in heart rate and an increase in arousal-related sympathetic-parasympathetic balance. These findings suggest small, potentially positive impacts of NIV on cardiovascular risk in children with concurrent obesity and OSA.

Factors related to positive airway pressure therapy adherence in children with obesity and sleep-disordered breathing.

STUDY OBJECTIVES: Positive airway pressure (PAP) is used to treat children with concurrent obesity and sleep-disordered breathing (SDB), but achieving adherence remains challenging. We aimed to identify factors associated with PAP adherence in a prospective cohort of children with obesity prescribed PAP for newly diagnosed SDB. METHODS: A questionnaire to assess factors related to PAP adherence was administered to participants and their parent ≥12 months after enrollment. Adherence (PAP use ≥4 hours/night on >50% of nights) was measured with PAP machine downloads, diaries, and physician assessments. Questionnaire responses were compared between adherent/nonadherent participants and between children/parents. Age, total and obstructive apnea-hypopnea index (OAHI), lowest oxygen saturation, and highest carbon dioxide were compared between adherent/nonadherent children with univariate differences of medians, with 95% confidence intervals. RESULTS: Fourteen children (median age: 14.3 years; 93% male; all with obstructive sleep apnea) were included. Eleven (79%) were adherent to PAP. SDB symptom improvement was reported in 9 of 14 children (64%); 8 of 14 children (57%) had positive experiences with PAP. Most children assumed an active role in PAP initiation and felt supported by the clinical team. Responses between adherent/nonadherent groups and between children/parents were similar. Oxygen saturation nadir (median difference between nonadherent and adherent groups: 8.9%; 95% confidence interval: 1.7, 16.1), but not age, apnea-hypopnea index, OAHI, or maximum carbon dioxide, was associated with PAP adherence. CONCLUSIONS: Children with obesity-related SDB with lower nocturnal oxygen saturation nadir were more likely to adhere to PAP therapy. Ensuring adequate understanding of PAP therapy and medical team support are key factors in PAP success.

Sleep Parameters and Overnight Urinary Melatonin Production in Children With Persistent Post-concussion Symptoms.

BACKGROUND: Sleep disturbance is common after a mild traumatic brain injury (mTBI) in children, yet its biology is poorly understood. We aimed to explore sleep-related problems (SRPs), sleep-activity patterns, and endogenous melatonin production in children with different recovery trajectories following mTBI. We hypothesized that children with delayed recovery would have more SRPs and abnormal sleep-activity patterns, which would correlate with lower overnight melatonin production. METHODS: In this prospective controlled cohort study, we enrolled 83 children with persistent symptoms, 26 children who had clinically recovered following mTBI, and 25 healthy controls. SRPs were evaluated using the sleep subscale of the Post-Concussion Symptom Inventory. Sleep actigraphy was performed for five to seven days at 37 (S.D. 7) days post-injury. Health-related quality of life and mood disturbance was assessed using the Child Health Questionnaire and the Behavior Assessment System for Children, respectively. Endogenous melatonin production was assessed using overnight urine collection. RESULTS: The groups were similar in age (13.9 [S.D. 2.6] years) and sex (52% female). Regression analysis demonstrated increased SRP in the symptomatic group (9.0; 95% confidence interval: 7.6, 11.1) compared with the recovered group (1.6; 95% confidence interval: 1.0, 2.4) and controls (2.0; 95% confidence intervals: 1.2, 3.2). Actigraphy parameters and urinary melatonin levels were not significantly different between groups. Neither SRPs nor actigraphy parameters correlated with anxiety and depression scores. CONCLUSIONS: Although children with persistent post-concussion symptoms reported more SRPs, this was not related to actigraphy sleep parameters or melatonin production. Further research is warranted to understand the pathophysiology of post-traumatic sleep disturbance.

Executive Coaching for Leadership Development: Experience of Academic Physician Leaders.

PURPOSE: To identify the perceived impact and benefit of executive coaching by a physician coach in the context of their leadership roles. METHOD: A descriptive qualitative inquiry was conducted. Individual semi-structured interviews ex post facto were conducted with physician leaders who completed an executive coaching program during the period 2015-2016.Interviews were transcribed verbatim, and data were analyzed by applying an emergent thematic analysis approach. RESULTS: Five interviews were conducted. Participants were female specialist physicians age 25-50 years with leadership experience that was minimal (one), more than two years (one), five years (one) or greater than 10 years (two). The experiences of the interview participants captured seven themes: isolation, time management, self-doubt, support, productivity, moving forward and workplace culture change/shift. For all participants, executive coaching appeared to positively impact their personal and professional development. There was a high degree of congruence in the experience of the executive coaching program by participants. CONCLUSIONS: The physician leaders who underwent a series of executive coaching sessions had very similar experiences overall. The added professional development tool of executive coaching for specialist physicians may have a significant role in supporting productivity, increasing workplace engagement and transforming the culture of medical practice.

Long-Term Impact of Sleep-Disordered Breathing on Quality of Life in Children With Obesity.

STUDY OBJECTIVES: (1) To determine baseline quality of life (QOL) among children with obesity and newly diagnosed moderate-severe sleep-disordered breathing (SDB) and to compare it to the reported QOL of children with obesity or SDB alone and healthy children. (2) To evaluate QOL change after 1 year. METHODS: A prospective multicenter cohort study was conducted in children (8-16 years) with obesity, prescribed positive airway pressure (PAP) therapy for moderate-severe SDB. Outcomes included parent-proxy and self-report total and subscale scores on the PedsQL questionnaire (baseline and 1-year). RESULTS: Total PedsQL scores were indicative of impaired QOL in 69% of cases based on parent-report and in 62% on self-report. Parents reported significantly lower QOL in our cohort than that reported in other studies for children with obesity or SDB alone or healthy children, on total PedsQL score and on social and psychosocial subscales. PedsQL total scores for participants were significantly higher (mean difference 7.3 ± 15.3, P = .03) than those reported by parents. Parents reported significant improvements in total PedsQL (mean change 7.29 ± 13.73, P = .04) and social functioning (mean change 17.65 ± 24.69, P = .04) scores after 1 year. No significant differences were found by children's self-report or by PAP adherence. CONCLUSIONS: QOL of children with obesity and SDB is lower than in children with obesity or SDB alone or healthy children. One year later, children reported no significant changes in QOL; parents reported significant improvements in total PedsQL and social functioning scores. PAP adherence did not significantly affect QOL change in this population. COMMENTARY: A commentary on this article appears in this issue on page 307.

Insulin Resistance and Hypertension in Obese Youth With Sleep-Disordered Breathing Treated With Positive Airway Pressure: A Prospective Multicenter Study.

STUDY OBJECTIVES: There is evidence that cardiometabolic disease associated with obesity and sleep-disordered breathing (SDB) in adults is present in youth. SDB is often treated with positive airway pressure (PAP) in youth with obesity. Our aims were to determine: (1) the prevalence of cardiometabolic disease and (2) whether PAP improves markers of cardiometabolic disease, in youth with obesity and newly diagnosed moderate-severe SDB. METHODS: A prospective multicenter cohort study was conducted in youth (8 to 16 years old) with obesity, prescribed PAP therapy for newly diagnosed moderate-severe SDB. Assessments occurred at baseline and at 6 and 12 months. Outcomes included markers of insulin resistance (change in homeostasis model assessment of insulin resistance (HOMA-IR) at 6 months = primary outcome), hypertension (24-hour ambulatory/blood pressure) and inflammation (high-sensitivity C-reactive protein: hs-CRP). RESULTS: Twenty-seven participants were enrolled. Of those with baseline testing available, 10/25 (40%) had HOMA-IR above the 97th percentile, 10/23 (44%) were hypertensive, 16/23 (70%) had loss of nocturnal blood pressure dip and hs-CRP was elevated in 16/27 (64%). There were no significant changes over time in markers of metabolic dysfunction or blood pressure, nor between PAP-adherent and non-adherent subgroups. CONCLUSIONS: In youth with obesity and SDB, metabolic dysfunction and hypertension were highly prevalent. There were no statistically significant improvements in cardiometabolic markers 1 year after the prescription of PAP therapy, although clinically relevant improvements were seen in insulin resistance and systolic blood pressure load, important predictors of future risk of cardiovascular disease. Larger, longer-term studies are needed to determine whether PAP improves cardiometabolic outcomes in obese youth. COMMENTARY: A commentary on this article appears in this issue on page 1025.

Incidence of children at risk for obstructive sleep apnea undergoing common day surgery procedures.

OBJECTIVE: The purpose of this study was to evaluate the prevalence of sleep-related breathing disorders (SRBD) in children undergoing elective day surgery procedures. METHODS: A validated Pediatric Sleep Questionnaire (PSQ) was distributed to the parents of children aged 2months to 18 years who met inclusion criteria and were undergoing urologic, otolaryngologic, and general surgical day surgery procedures a 3-month period of time. The prevalence of children at risk for pediatric SRBD was determined from PSQ results. RESULTS: From a total of 288 PSQ Questionnaires, 9.1% of urology, 11.1% of general surgery, and 51.9% of otolaryngology patients admitted to day surgery were found to be at risk for sleep disordered breathing. The median PSQ score for the children at risk was 9.2 for urological surgeries, 10.9 for general surgery, and 11.3 for otolaryngological procedures. CONCLUSIONS: There is an increased prevalence of children at risk of SRBD awaiting common day surgery procedures than previously expected based on existing literature. Patients undergoing otolaryngological procedures were at greater risk of sleep-related breathing disorders when compared with patients undergoing urological or general surgical procedures. There may be a role for screening of pediatric patients with a PSQ prior to day-surgery. LEVEL OF EVIDENCE: Type of study: prognosis study, level IV.

Noninvasive monitoring of CO2 during polysomnography: a review of the recent literature.

PURPOSE OF REVIEW: Sleep-related breathing disorders are complex conditions that require the integration of clinical and sleep laboratory findings to support a diagnosis. Analysis of carbon dioxide (CO2) levels during sleep provides important additional information to the clinician that is not obtained from other polysomnographic indices, and that may have a direct impact on both diagnosis and patient mortality. Although arterial blood gas (ABG) is considered the gold standard for assessing PaCO2 levels, there are numerous drawbacks. Noninvasive methods for PaCO2 estimation include end-tidal and transcutaneous monitoring, which allow for continuous monitoring of trends. RECENT FINDINGS: Review of the recent literature suggests that transcutaneous methods correlate strongly with PaCO2 levels and can provide an accurate surrogate in replacement of ABGs. End-tidal methods provide breath to breath information that can be used to assess hypoventilation; however, they have more variability, especially in patients with increased dead space and small tidal volumes. To date, however, there are limited studies investigating noninvasive CO2 monitoring during sleep. SUMMARY: Given the benefits of CO2 monitoring and the importance of assessing for hypercapnia, noninvasive continuous CO2 monitoring should be considered for all patients undergoing polysomnography.

Non-respiratory indications for polysomnography and related procedures in children: an evidence-based review.

OBJECTIVE: This evidence-based review provides a systematic and comprehensive review of the literature regarding the utility of polysomnography for the evaluation of non-respiratory sleep disorders in children including hypersomnias, parasomnias, sleep-related movement disorders, and sleep in other special populations. METHODS: A task force of pediatric sleep medicine experts performed a systematic review of the literature regarding the use of polysomnography for non-respiratory sleep disorders in children. They identified and graded 76 papers as evidence. RESULTS: The main results include (1) polysomnography combined with the multiple sleep latency test is useful for evaluating disorders of excessive somnolence to objectively quantify sleepiness. The results have to be interpreted with consideration of the pubertal stage and regularity of the sleep patterns of the child; (2) polysomnography is indicated in children with parasomnias or sleep related movement disorders who have a high likelihood of having obstructive sleep apnea (OSA); (3) polysomnography is not routinely indicated in children with enuresis unless there is a high likelihood of OSA; (4) polysomnography can be helpful in evaluating children with restless legs syndrome (RLS) and when periodic limb movement disorder (PLMD) is suspected. CONCLUSIONS: These findings suggest that, in children with non-respiratory sleep disorders, polysomnography should be a part of a comprehensive sleep evaluation in selected circumstances to determine the nature of the events in more detail or when the suspicion of OSA is relatively high.

Executive summary of respiratory indications for polysomnography in children: an evidence-based review.

OBJECTIVE: This comprehensive, evidence-based review provides a systematic analysis of the literature regarding the validity, reliability, and clinical utility of polysomnography for characterizing breathing during sleep in children. Findings serve as the foundation of practice parameters regarding respiratory indications for polysomnography in children. METHODS: A task force of content experts performed a systematic review of the relevant literature and graded the evidence using a standardized grading system. Two hundred forty-three evidentiary papers were reviewed, summarized, and graded. The analysis addressed the operating characteristics of polysomnography as a diagnostic procedure in children and identified strengths and limitations of polysomnography for evaluation of respiratory function during sleep. RESULTS: The analysis documents strong face validity and content validity, moderately strong convergent validity when comparing respiratory findings with a variety of relevant independent measures, moderate-to-strong test-retest validity, and limited data supporting discriminant validity for characterizing breathing during sleep in children. The analysis documents moderate-to-strong test-retest reliability and interscorer reliability based on limited data. The data indicate particularly strong clinical utility in children with suspected sleep related breathing disorders and obesity, evolving metabolic syndrome, neurological, neurodevelopmental, or genetic disorders, and children with craniofacial syndromes. Specific consideration was given to clinical utility of polysomnography prior to adenotonsillectomy (AT) for confirmation of obstructive sleep apnea syndrome. The most relevant findings include: (1) recognition that clinical history and examination are often poor predictors of respiratory polygraphic findings, (2) preoperative polysomnography is helpful in predicting risk for perioperative complications, and (3) preoperative polysomnography is often helpful in predicting persistence of obstructive sleep apnea syndrome in patients after AT. No prospective studies were identified that address whether clinical outcome following AT for treatment of obstructive sleep apnea is improved in association with routine performance of polysomnography before surgery in otherwise healthy children. A small group of papers confirm the clinical utility of polysomnography for initiation and titration of positive airway pressure support. CONCLUSIONS: Pediatric polysomnography shows validity, reliability, and clinical utility that is commensurate with most other routinely employed diagnostic clinical tools or procedures. Findings indicate that the "gold standard" for diagnosis of sleep related breathing disorders in children is not polysomnography alone, but rather the skillful integration of clinical and polygraphic findings by a knowledgeable sleep specialist. Future developments will provide more sophisticated methods for data collection and analysis, but integration of polysomnographic findings with the clinical evaluation will represent the fundamental diagnostic challenge for the sleep specialist.

Preverbal photoscreening for amblyogenic factors and outcomes in amblyopia treatment: early objective screening and visual acuities.

BACKGROUND: Previous studies have suggested that infant photoscreening yields better results than visual acuity screening in preschool-aged children. With conventional vision screening, the patient must be able to provide monocular visual acuity cooperation, whereas objective screening for amblyogenic factors can be done at much younger ages. METHODS: From February 1996 through February 2006, Alaska Blind Child Discovery photoscreened 21,367 rural and urban Alaskan children through grade 2, with an 82% positive predictive value (ie, true number of those referred); 6.9% were referred for a complete eye examination and treatment. All "referred" interpreted images for children younger than 48 months who were then followed up and treated for more than 2 years were reviewed to determine whether treatment was successful. RESULTS: Of 411 "positive" screening photos from children younger than 4 years, 94 patients had more than 2 years follow-up. The 36 children photoscreened before age 2 years had a mean treated visual acuity of 0.17 logarithm of the minimum angle of resolution (logMAR), which was significantly better than that of 58 children screened between ages 25 and 48 months (mean, 0.26 logMAR). Despite similar levels of amblyogenic risk factors, the proportion of children failing to reach a visual acuity of 20/40 was significantly less among those screened before age 2 years (5%) than in those screened from ages older than 2.0 years and younger than 4.0 years (17%). CONCLUSION: Very early photoscreening yields better visual outcomes in amblyopia treatment compared with later photoscreening in preschool-aged children.

Compliance rates in children using noninvasive continuous positive airway pressure.

STUDY OBJECTIVES: For a subpopulation of children with obstructive sleep apnea, the mainstay of treatment is nasal continuous positive airway pressure (nCPAP). Accurate measures of "time in use" have not been used to assess compliance with nCPAP in large numbers of children. Data from a comprehensive nCPAP program are used to describe nCPAP use among children aged 6 months to 18 years and provide time-in-use compliance rates. DESIGN: Retrospective cohort study SETTING: University Pediatric Teaching Hospital INTERVENTIONS: Initiation of nCPAP treatment MEASUREMENTS AND RESULTS: Seventy-nine children were identified as requiring treatment with nCPAP, with 65 (82%) successfully established on nCPAP during the 46-month study period. Objective compliance data were available on 50 children: 66% were boys, 78% had a complicating medical disorder, the mean age was 10 +/- 5.1 years, and the median apnea-hypopnea index was 11.3 (interquartile range, 5.4-25.9). Follow-up ranged from 8 to 979 days. Forty-eight percent of children used nCPAP immediately. Seventy-six percent of children used nCPAP for at least half the days, with use defined as 1 or more hours of recording during a 24-hour period. Mean daily use was 4.7 hours (interquartile range, 1.4-7.0), and mean daily use on days nCPAP was used was 6.3 hours (interquartile range, 3.3-8.5) CONCLUSIONS: With patience, a behavioral modification approach, and parental commitment, children will be accepting of nCPAP and reasonably compliant with treatment.

Continuous positive airway pressure for children: a discussion on how to maximize compliance.

As pediatric sleep facilities and resources expand, increasing numbers of children with sleep-disordered breathing requiring continuous positive airway pressure (CPAP) treatment are being identified. Despite extensive expertise in treating adults with CPAP, many centres have little experience using CPAP in the pediatric population. The successful initiation and continued effective treatment with CPAP requires a unique and specialized approach to the pediatric patient and their family. Nearly, half of children needing CPAP will be uncooperative upon initial exposure to this unusual treatment. This review aims to outline an approach to the successful initiation of CPAP treatment in children including some trouble-shooting strategies to maximize initial and ongoing compliance with prescribed therapy.

Transcutaneous carbon dioxide monitoring and capnography during pediatric polysomnography.

INTRODUCTION: Transcutaneous monitoring and capnography are 2 surrogate methods of measuring arterial carbon dioxide levels employed by pediatric sleep laboratories. Both techniques are noninvasive, validated, and quantitative indirect predictors of arterial carbon dioxide level, and both have been widely adopted for use during pediatric and adult polysomnography (PSG). We hypothesized that there would be close agreement between the two techniques when compared in a pediatric population. METHODS: Children referred for diagnostic polysomnography to the Pediatric Sleep Laboratory at the Alberta Children's Hospital from June 2000 to October 2003 were included. All subjects underwent an overnight computerized PSG as per American Thoracic Society standards, including both transcutaneous and end-tidal monitoring. A registered PSG technician manually scored studies and eliminated all CO2 data that was not interpretable. Total "uninterpretable data" time was calculated for both channels. Statistical analysis of the level of agreement between transcutaneous and end-tidal signals was performed using a Bland-Altman analysis. RESULTS: The PSG studies of 609 children (363 males), mean age 7.9 +/- 4.6 years (range 0.1-18.4), were reviewed. On average, interpretable data was available for 61.8% +/- 35.1% and 71.5% +/- 25.2 % of total recording time from the end-tidal and transcutaneous channels respectively. The maximum and mean CO2 measurements obtained by both devices showed close agreement with a mean difference of 0.1 +/- 5.4 mm Hg and 0.6 +/- 3.9 mm Hg respectively. CONCLUSION: Transcutaneous and end-tidal carbon dioxide monitoring during polysomnography are well tolerated and provide interpretable and comparable results in the majority of children.

Periodic limb movements in children: prevalence in a referred population.

STUDY OBJECTIVES: To determine the prevalence of periodic limb movements of sleep (PLMS) in children referred for evaluation of sleep disorders. DESIGN: A retrospective analysis of all overnight polysomnograms (PSG) performed at a tertiary-level pediatric care facility. SETTING: All PSG studies were performed in the pediatric sleep laboratory associated with the Alberta Children's Hospital in Calgary, AB, Canada. The pediatric sleep laboratory was situated in the Foothills Hospital Alberta Lung Association Sleep Center until August 2002. At that time, the pediatric sleep laboratory was relocated to the Alberta Children's Hospital. PARTICIPANTS: All children of any age undergoing PSG for any reason between October 1999 and March 2003. MEASUREMENTS AND RESULTS: All PSG records were reviewed, and the following data was extracted: periodic limb movement index (PLM index), periodic limb movements with arousal index (PLM w/arousal index), apnea-hypopnea index (AHI), and patient demographics (age, sex, comorbidities). A total of 591 PSG studies were reviewed. Thirty-three of the 591 children (5.6%) had evidence of PLMs > 5 per hour. Twenty of the 33 (60.0%) had coexistent obstructive sleep apnea (AHI > 1/hour). Only 7 of the 591 children studied (1.2%) had evidence of PLM > 5 per hour with no other comorbidity. Two of 13 children with PLM > 5 per hour and no evidence of obstructive sleep apnea had attention-deficit/hyperactivity disorder. The prevalence of PLMS in the 28 of the 591 subjects with a preexisting diagnosis of ADHD was increased at 7.1%. CONCLUSIONS: PLMS is an uncommon disorder of childhood. In a select population at increased risk for having a sleep disorder, the prevalence of isolated PLMS is only 1.2%.