Accuracy of a smartphone application in estimating sleep in children.

PURPOSE: Chronic sleep problems can lead to difficulties for both the individual and society at large, making it important to effectively measure sleep. This study assessed the accuracy of an iPhone application (app) that could potentially be used as a simple, inexpensive means to measure sleep over an extended period of time in the home. METHODS: Twenty-five subjects from the ages of 2-14 who were undergoing overnight polysomnography (PSG) were recruited. The phone was placed on the mattress, near their pillow, and recorded data simultaneously with the PSG. The data were then downloaded and certain parameters were compared between the app and PSG, including total sleep time, sleep latency, and time spent in various defined "stages." RESULTS: Although there seemed to be a visual relationship between the graphs generated by the app and PSG, this was not confirmed on numerical analysis. There was no correlation between total sleep time or sleep latency between the app and PSG. Sleep latency from the PSG and latency to "deep sleep" from the app had a significant relationship (p = 0.03). No combination of PSG sleep stages corresponded with app "stages" in a meaningful way. CONCLUSIONS: The Sleep Cycle App may have value in increasing the user's awareness of sleep issues, but it is not yet accurate enough to be used as a clinical tool.

Insulin-like growth factor-I and insulin-like growth factor binding protein-1 are related to cardiovascular disease biomarkers in obese adolescents.

CONTEXT: Insulin-like growth factor (IGF)-I and IGF binding protein (IGFBP)-1 have been linked to cardiovascular disease (CVD) risk and pathophysiology in adults, but there are limited data in youth. OBJECTIVE: The aim of the study was to examine the relationship between IGF and IGFBP-1 with traditional and non-traditional CVD risk factors including inflammatory markers and body composition in an obese pediatric cohort. DESIGN: A cross-sectional study. SETTING: The study was carried out at a university children's hospital. SUBJECTS: Sixty-one obese non-diabetic adolescents. OUTCOMES: Fasting IGF-I, IGFBP-1, lipoprotein profiles, high-sensitivity C-reactive protein (hsCRP), and total adiponectin as well as insulin sensitivity measures, blood pressure (BP), and anthropometrics. RESULTS: IGFBP-1 was negatively associated with insulin sensitivity measures, body mass index (BMI), and diastolic BP in males. IGF-I was negatively associated with hsCRP (r = -0.479, p < 0.0005), and IGFBP-1 was positively associated with adiponectin (r = 0.545, p < 0.0005). The IGF-I/CRP and IGFBP-1/adiponectin associations remained significant when controlling for both BMI and insulin sensitivity index (SI ). Both IGF-I and IGFBP-1 were negatively associated with waist circumference (r = -0.327 and r = -0.275, respectively) and sagittal abdominal diameter (r = -0.333 and r = -0.371, respectively), while IGFBP-1 was negatively associated with fat mass (r = -0.347, p = 0.01) as well as neck circumference and fat-free mass in males. Controlling for BMI z-score and SI , IGFBP-1 remained negatively associated with diastolic blood pressure (r = 0.706, p = 0.001 and neck circumference (r = -0.548, p = 0.15) in males. CONCLUSIONS: IGF-I and IGFBP-1 associate with CVD risk markers and may add to clinical assessments of cardiometabolic dysfunction in youth.

Relationship between sleep, sleep apnea, and neuropsychological function in children with Down syndrome.

PURPOSE: To determine whether sleep and sleep disordered breathing (SDB) contribute to the neuropsychological deficits of patients with Down syndrome, and whether treatment of SDB results in improvement in cognitive function. METHODS: In this cohort study, 25 children with Down syndrome underwent overnight polysomnography (PSG), Multiple Sleep Latency Testing (MSLT), and a battery of neuropsychological tests. Patients with SDB underwent a follow up PSG after treatment. All patients repeated the neuropsychological tests 13 months later. RESULTS: At baseline, there was no relationship between SDB and performance on the neuropsychological tests. However, total sleep time and sleep latency were related to tests of cognitive ability (p < 0.05) and comprehension (p < 0.01). The amount of time in slow-wave sleep correlated with tests of achievement (p < 0.01), and adaptive behavior (p < 0.01). Ten patients had SDB confirmed on PSG. Five of these patients were treated successfully with adenotonsillectomy and/or continuous positive airway pressure. The five who did not tolerate treatment were deficient in tests of adaptive behavior (Vineland p < 0.05) visual-motor integration (Beery p < 0.01) and achievement (Woodcock-Johnson p < 0.05) compared to those successfully treated. After treatment the patients improved in ratings of attention (Conners p < 0.05). CONCLUSIONS: Although SDB is common in children with Down syndrome, it is not a major contributor to their cognitive deficits. Cognitive function is related to the amount of sleep and particularly slow wave sleep. Successful treatment of SDB may improve their attention.

Accuracy of computer algorithms and the human eye in scoring actigraphy.

PURPOSE: The purpose of this study is to determine the optimal scoring method and parameter settings of actigraphy by comparison to simultaneous polysomnography (PSG). METHODS: Fifteen studies of simultaneous PSG and actigraphy were completed in adolescents (mean age = 16.3 years) and analyzed. Scoring actigraphy by the human eye was compared to a commercial computerized algorithm using various parameters. The PSG was considered the reference standard. RESULTS: There was a better correlation between actigraphy and PSG sleep start/end, total sleep time, wake after sleep onset, and sleep efficiency when the rest period was determined by the human (mean r = 0.640) rather than auto-set by the software (r = 0.406). The best results came when the rest intervals were set based on the PSG (r = 0.694). Scoring the printed actogram by the human eye was superior to the auto analyses as well (r = 0.575). Higher correlations and lower biases were obtained from lower wake threshold settings (low and medium) and higher immobility times (10 and 15 min). CONCLUSIONS: Visual scoring by simple inspection of the actigraphy tracing had a reasonable correlation with the gold standard PSG. Accurate determination of the rest interval is important in scoring actigraphy. Scoring actigraphy by the human eye is superior to this computer algorithm when auto-setting major rest periods. A low wake threshold and 10-15 min of immobility for sleep onset and sleep end yield the most accurate computerized results. Auto-setting major rest intervals should be avoided to set start/end of rest intervals; adjustments for artifacts and/or a sleep diary for comparison are helpful.

Rates of diagnoses of sleep disorders in children with chronic medical conditions.

STUDY OBJECTIVES: This investigation examines sleep disorder (SD) diagnoses in a large population of children and adolescents with chronic medical conditions (CMCs). Little is known about SD diagnoses in this population. The large population used in this study allowed examination of SD rates by CMC type and demographics. METHODS: Data were from the Coordinated Health Care for Complex Kids (CHECK) project designed for Medicaid-funded children and adolescents with at least 1 CMC from a large metropolitan area. The study population (n = 16,609) was limited to children and adolescents, 0 to 18 years of age. SD and CMC diagnoses were obtained from Medicaid claims data. RESULTS: Fourteen percent of the population (mean age of 9.1 years [standard deviation = 5.2]; 35.8% African American; 56.4% male; 77 with more than 1 CMC) received a sleep disorder diagnosis. The most frequent diagnosis was sleep-disordered breathing (11.2%), followed by nocturnal enuresis (1.2%) and insomnia (1%). SDs were diagnosed more frequently in those with multiple CMCs than in those with 1 CMC (19.7% vs 5.8%; P < .001). Insomnia rates in Hispanic/Latinx (1.2%) and African American (0.8%) children and adolescents were significantly lower (both P < .001) than in Caucasians (3.5%). Odds of receiving a sleep diagnosis varied among CMCs. CONCLUSIONS: Our analysis of Medicaid claims data of a large urban cohort offers detailed information about the rates of sleep diagnoses and suggests underdiagnosis of SDs in this vulnerable, high-risk, primarily ethnic minority population. Underrecognition of sleep disorders has short- and long-term health and economic consequences. Study results may help clinicians implement appropriate SD screening and management for children and adolescents with CMCs. CITATION: Adavadkar PA, Pappalardo AA, Glassgow AE, et al. Rates of diagnoses of sleep disorders in children with chronic medical conditions. J Clin Sleep Med. 2022;18(8):2001-2007.

Visceral adiposity is related to insulin sensitivity and inflammation in adolescents with obesity and mild sleep disordered breathing.

OBJECTIVES: To evaluate the relationships between adipose tissue distribution, insulin secretion and sensitivity, sleep-disordered breathing, and inflammation in obese adolescents. METHODS: Cross-sectional study of 56 obese adolescents who underwent anthropometric measures, dual-energy X-ray absorptiometry, overnight polysomnography, oral glucose tolerance test (OGTT) and frequently sampled intravenous glucose tolerance test. Correlation and regression analyses were used to assess relationships between adiposity, insulin secretion and sensitivity, measures of sleep-disordered breathing (oxyhemoglobin nadir, SpO2; apnea hypopnea index, AHI; arousal index, AI; maximum end-tidal CO2; non-REM sleep duration), and inflammation (high-sensitivity C-reactive protein, hsCRP). RESULTS: Subjects (55% female) were mean (SD) 14.4 (2.1) years, with BMI Z-score of 2.3 (0.4). AHI was >5 in 10 (18%) subjects and 1< AHI ≤5 in 22 (39%). Visceral adipose tissue area (VAT) was positively correlated with OGTT 1 and 2 h insulin and 1 h glucose, and hsCRP (r=0.3-0.5, p≤0.007 for each). VAT was negatively correlated with sensitivity to insulin (r=-0.4, p=0.005) and SpO2 nadir (r=-0.3, p=0.04) but not with other sleep measures. After adjustment for BMI-Z, sex, population ancestry, age, and sleep measures, VAT remained independently associated with insulin measures and 1 h glucose, but no other measures of glycemia. SAT was not associated with measures of glycemia or insulin resistance. CONCLUSIONS: Among adolescents with obesity, visceral adiposity was associated with insulin resistance, SpO2 nadir, and inflammation. The independent association of visceral adiposity with insulin resistance highlights the potential role of VAT in obesity-related chronic disease.

Adenotonsillectomy outcomes in treatment of obstructive sleep apnea in children: a multicenter retrospective study.

RATIONALE: The overall efficacy of adenotonsillectomy (AT) in treatment of obstructive sleep apnea syndrome (OSAS) in children is unknown. Although success rates are likely lower than previously estimated, factors that promote incomplete resolution of OSAS after AT remain undefined. OBJECTIVES: To quantify the effect of demographic and clinical confounders known to impact the success of AT in treating OSAS. METHODS: A multicenter collaborative retrospective review of all nocturnal polysomnograms performed both preoperatively and postoperatively on otherwise healthy children undergoing AT for the diagnosis of OSAS was conducted at six pediatric sleep centers in the United States and two in Europe. Multivariate generalized linear modeling was used to assess contributions of specific demographic factors on the post-AT obstructive apnea-hypopnea index (AHI). MEASUREMENTS AND MAIN RESULTS: Data from 578 children (mean age, 6.9 +/- 3.8 yr) were analyzed, of which approximately 50% of included children were obese. AT resulted in a significant AHI reduction from 18.2 +/- 21.4 to 4.1 +/- 6.4/hour total sleep time (P < 0.001). Of the 578 children, only 157 (27.2%) had complete resolution of OSAS (i.e., post-AT AHI <1/h total sleep time). Age and body mass index z-score emerged as the two principal factors contributing to post-AT AHI (P < 0.001), with modest contributions by the presence of asthma and magnitude of pre-AT AHI (P < 0.05) among nonobese children. CONCLUSIONS: AT leads to significant improvements in indices of sleep-disordered breathing in children. However, residual disease is present in a large proportion of children after AT, particularly among older (>7 yr) or obese children. In addition, the presence of severe OSAS in nonobese children or of chronic asthma warrants post-AT nocturnal polysomnography, in view of the higher risk for residual OSAS.

Catecholamines, adiponectin, and insulin resistance as measured by HOMA in children with obstructive sleep apnea.

INTRODUCTION: Obstructive sleep apnea (OSA) has been implicated in the pathophysiology of metabolic syndrome. Its contribution to insulin resistance is complicated by obesity and puberty. We hypothesized that OSA is associated with worse insulin resistance and lower adiponectin after adjustment for obesity and puberty and that catecholamines might mediate these changes. METHODS: Normal controls and children with suspected OSA were recruited and categorized as pubertal or prepubertal. Overnight polysomnography (PSG) was performed. Subjects were categorized as OSA for total apnea hypopnea index (Total-AHI) > or = 1.5 events/h. Fasting blood glucose, insulin, adiponectin, and 24-hour urinary catecholamines were obtained. Homeostatic model assessment of insulin resistance (HOMA) was calculated. The independent effects of OSA upon HOMA, adiponectin, and urinary catecholamines following adjustment for body mass index (BMI) were determined. RESULTS (median; min, max): Subjects (n = 98, 42F; 11 +/- 4 years, 37 prepubertal) were generally overweight (BMI-Z = 2.1; -3, 4.1) and had wide-ranging insulin sensitivities (HOMA = 2.7; 0.5, 27) and PSG parameters (Total-AHI = 1.6; 0, 185). The risks of elevated insulin (P = 0.04) and HOMA (P = 0.05) were higher in OSA vs non OSA obese pubertal children. Polysomnographic markers of OSA, including Total-AHI (P = 0.001, R2 = 0.32), were negatively associated with adiponectin in pubertal children. Total-AHI and oxygen desaturation were associated with higher urinary normetanephrine and norepinephrine. CONCLUSIONS: In obese pubertal children, OSA was associated with worse insulin resistance. Worsening OSA was associated with lower adiponectin and increasing urinary catecholamines. Whether OSA directly lowers adiponectin and aggravates a predisposition to insulin resistance is unknown, but these preliminary findings highlight the importance of further studying pediatric OSA.

The relationship between sleep-disordered breathing, blood pressure, and urinary cortisol and catecholamines in children.

STUDY OBJECTIVES: Hypertension is a complication of obstructive sleep apnea (OSA) syndrome in adults. A correlation between OSA syndrome and elevated blood pressure (BP) is suggested in children, but its pathogenesis remains unclear. Our aim was to study the effects of sleep and sleep apnea on BP and sympathetic nervous system activation as measured by serum cortisol and urinary catecholamines. We hypothesized that children with OSA syndrome would have higher BP, urinary catecholamines, and cortisol compared with controls. METHODS: We measured BP during polysomnography in 78 children with suspected sleep-disordered breathing and 18 nonsnoring controls. BP was measured during wakefulness and every 30-60 minutes throughout the night. All participants had 24-hour urinary catecholamine and free cortisol collections 48 hours before polysomnography. RESULTS: BP varied with sleep stage; it was highest during wakefulness and N1 and lowest during non-rapid eye movement stage 3. Children classified as high apnea-hypopnea index (AHI) snorers (AHI >5 events/h) had a greater prevalence of systolic hypertension (57%) than low-AHI snorers (22%) and nonsnoring controls (22%; P = .04). The high-AHI snorers also had higher diastolic BP (P < .02) as well as blunted nocturnal diastolic BP changes during sleep (P = .02) compared with low-AHI snorers (AHI <5 events/h). Twenty-hour urinary free cortisol and 24-hour urinary catecholamines were not associated with BP. CONCLUSIONS: BP in children varies with sleep stage. OSA is associated with systolic hypertension, higher BP during rapid eye movement sleep, as well as elevation of diastolic BP and blunted BP changes with sleep.

Polysomnographic values in children undergoing puberty: pediatric vs. adult respiratory rules in adolescents.

STUDY OBJECTIVES: Polysomnographic respiratory events in children should be scored using pediatric respiratory rules. However, due to a lack of data on adolescents, recently revised rules allow children aged 13-18 years to be scored by adult or pediatric criteria. To clarify which criteria to use, we describe the evolution of respiratory events with Tanner stage, and we compare events in children aged 13-18 years with the new American Academy of Sleep Medicine adult and pediatric respiratory rules. DESIGN: Cross-sectional SETTING: Academic hospital PARTICIPANTS: Healthy subjects aged 8-18 years recruited for research purposes. INTERVENTIONS: Physical examination to determine Tanner stage, overnight polysomnogram, and determination of sex hormones. RESULTS: Sixty-eight subjects (Tanner 1-5) were studied, mean age [SD] = 13 +/- 3 years, median apnea hypopnea index (AHI)= 0.1 (range: 0-1.2)/h. The median percentages of total sleep time (TST) with SpO2 < 92% were 0.1 (0-4.2)%, and with end-tidal CO2 > 50 torr was 0.1 (0-88.6)%. Thirty-two subjects were aged 13-18 years, (Tanner 3-5). The difference between AHI scored by pediatric (median = 0 [0-0.9]/h) and adult (median = 0 [0 - 0.5]/h) criteria was statistically significant (P = 0.043), but not clinically relevant. CONCLUSIONS: Respiratory events in normal children aged 8-18 years are rare and unrelated to Tanner stage. Adult or pediatric respiratory rules can be used for scoring polysomnograms in asymptomatic subjects approaching adulthood. Further studies are needed in symptomatic children within this age group.

Diagnosis and evaluation of obstructive sleep apnoea in children.

INTRODUCTION: The aim of this article is to review the medical literature and describe clinical and laboratory findings in children with obstructive sleep apnoea (OSA) to differentiate children with OSA from those with primary snoring or other disorders, with a particular focus on Asian children. METHODS: Medline search via Pub Med, search terms sleep apnoea and children; and sleep apnoea and children and Asian. RESULTS AND CONCLUSIONS: Children with OSA usually present with snoring, daytime sleepiness, and/or difficulties in school or behaviour. The prevalence of OSA in Asian children is less than that of other groups, but the severity of the disorder on presentation may be greater. Overnight polysomnography remains the diagnostic "gold standard"; limited studies, or studies in the home, are not sufficient to exclude OSA in a child with suggestive symptoms, nor can they reliably assess the severity of the disorder which is important in planning treatment. Limited studies may, however, be useful in large-scale research studies.

Relationship between REM density, duty cycle, and obstructive sleep apnea in children.

STUDY OBJECTIVES: The pattern and distribution of rapid eye movement (REM) sleep changes during development, yet there have been few studies of REM density in children. Although children with obstructive apnea syndrome (OSAS) obstruct primarily during REM sleep, the relationship between REM density and obstructive apnea has not been established for this population. We hypothesized that (i) REM density and REM cycle duration increases over the course of the night in children, (ii) the duty cycle (inspiratory time divided by respiratory cycle time) increases over the course of the night in children with suspected OSAS, and (iii) the increase in REM density over the course of the night is associated with increased severity of obstructive apnea. DESIGN: REM density and respiratory parameters were measured during polysomnography. SETTING: Sleep laboratory PATIENTS: 76 children with suspected OSAS. INTERVENTIONS: NA MEASUREMENTS AND RESULTS: REM density and the duration of REM cycles increased over the course of the night until the fifth REM cycle, and then stabilized. The duty cycle increased across the first 6 REM cycles. However, the apnea hypopnea index (AHI) did not increase across REM cycles, and was not affected by the changes in REM density or duty cycle. We speculate that the increase in the duty cycle is a compensatory response to increased upper airway loads during sleep, and that this may lead to ventilatory or upper airway muscle fatigue.

Recommended Amount of Sleep for Pediatric Populations: A Consensus Statement of the American Academy of Sleep Medicine.

ABSTRACT: Sleep is essential for optimal health in children and adolescents. Members of the American Academy of Sleep Medicine developed consensus recommendations for the amount of sleep needed to promote optimal health in children and adolescents using a modified RAND Appropriateness Method. The recommendations are summarized here. A manuscript detailing the conference proceedings and the evidence supporting these recommendations will be published in the Journal of Clinical Sleep Medicine.

Consensus Statement of the American Academy of Sleep Medicine on the Recommended Amount of Sleep for Healthy Children: Methodology and Discussion.

ABSTRACT: Members of the American Academy of Sleep Medicine developed consensus recommendations for the amount of sleep needed to promote optimal health in children and adolescents using a modified RAND Appropriateness Method. After review of 864 published articles, the following sleep durations are recommended: Infants 4 months to 12 months should sleep 12 to 16 hours per 24 hours (including naps) on a regular basis to promote optimal health. Children 1 to 2 years of age should sleep 11 to 14 hours per 24 hours (including naps) on a regular basis to promote optimal health. Children 3 to 5 years of age should sleep 10 to 13 hours per 24 hours (including naps) on a regular basis to promote optimal health. Children 6 to 12 years of age should sleep 9 to 12 hours per 24 hours on a regular basis to promote optimal health. Teenagers 13 to 18 years of age should sleep 8 to 10 hours per 24 hours on a regular basis to promote optimal health. Sleeping the number of recommended hours on a regular basis is associated with better health outcomes including: improved attention, behavior, learning, memory, emotional regulation, quality of life, and mental and physical health. Regularly sleeping fewer than the number of recommended hours is associated with attention, behavior, and learning problems. Insufficient sleep also increases the risk of accidents, injuries, hypertension, obesity, diabetes, and depression. Insufficient sleep in teenagers is associated with increased risk of self-harm, suicidal thoughts, and suicide attempts. COMMENTARY: A commentary on this article apears in this issue on page 1439.

Infant polysomnography: reliability and validity of infant arousal assessment.

Infant arousal scoring based on the Atlas Task Force definition of transient EEG arousal was evaluated to determine (1). whether transient arousals can be identified and assessed reliably in infants and (2). whether arousal and no-arousal epochs scored previously by trained raters can be validated reliably by independent sleep experts. Phase I for inter- and intrarater reliability scoring was based on two datasets of sleep epochs selected randomly from nocturnal polysomnograms of healthy full-term, preterm, idiopathic apparent life-threatening event cases, and siblings of Sudden Infant Death Syndrome infants of 35 to 64 weeks postconceptional age. After training, test set 1 reliability was assessed and discrepancies identified. After retraining, test set 2 was scored by the same raters to determine interrater reliability. Later, three raters from the trained group rescored test set 2 to assess inter- and intrarater reliabilities. Interrater and intrarater reliability kappa's, with 95% confidence intervals, ranged from substantial to almost perfect levels of agreement. Interrater reliabilities for spontaneous arousals were initially moderate and then substantial. During the validation phase, 315 previously scored epochs were presented to four sleep experts to rate as containing arousal or no-arousal events. Interrater expert agreements were diverse and considered as noninterpretable. Concordance in sleep experts' agreements, based on identification of the previously sampled arousal and no-arousal epochs, was used as a secondary evaluative technique. Results showed agreement by two or more experts on 86% of the Collaborative Home Infant Monitoring Evaluation Study arousal scored events. Conversely, only 1% of the Collaborative Home Infant Monitoring Evaluation Study-scored no-arousal epochs were rated as an arousal. In summary, this study presents an empirically tested model with procedures and criteria for attaining improved reliability in transient EEG arousal assessments in infants using the modified Atlas Task Force standards. With training based on specific criteria, substantial inter- and intrarater agreement in identifying infant arousals was demonstrated. Corroborative validation results were too disparate for meaningful interpretation. Alternate evaluation based on concordance agreements supports reliance on infant EEG criteria for assessment. Results mandate additional confirmatory validation studies with specific training on infant EEG arousal assessment criteria.

Ontogeny of arousal.

Ontogeny of arousal data constitute a vital supplement to the sparse literature on spontaneous neuronal activity. These data demonstrate that measurable infant spontaneous arousals (SAs) with an inherent oscillatory entrainment occur six times more in active sleep than in quiet sleep of the same duration and are identifiable as a human neurobiologic function. These SAs are not significantly associated with race or ethnicity, gender, total hours spent sleeping, percent time spent in active or quiet sleep, preterm status, history of a life-threatening event, having had a sibling who died of sudden infant death syndrome (SIDS), or having had a mother who smoked during this pregnancy. As measurable neurophysiologic events, SAs establish parameters for research at molecular and molar levels focusing on several critical areas: (1) the neuronal control of SA related to neurotransmitters, (2) as a significant antecedent factor in clinical cardiorespiratory events occurring in infants at high epidemiologic risk for SIDS; (3) as a regulatory biologic factor underlying temperament and executive cognitive functioning, and (4) morbidity and mortality effects possibly related to therapeutic interventions that alter SA levels.

Prevalence of periodic limb movements during sleep in normal children.

STUDY OBJECTIVES: Although the American Academy of Sleep Medicine (AASM) mandates that periodic limb movements during sleep (PLMS) be scored on every polysomnogram, and considers a periodic limb movement index (PLMI) > 5/h abnormal in children, there is a lack of community-derived data regarding the prevalence of PLMS in children, and no data to support this cutoff value. Therefore, the aim of this study was to determine the prevalence of PLMS in a sample of normal children. DESIGN: Retrospective study. PARTICIPANTS: 195 healthy, non-snoring children aged 5-17 years, recruited from the community, who underwent polysomnography for research purposes. METHODS: PLMS were scored using the AASM 2007 criteria. MEASUREMENTS AND RESULTS: The group age (median [IQR]) was 12.9 [10-15] years, and 58% were male. Sleep architecture was normal, and the obstructive apnea hypopnea index was 0.1 [0-0.3]/h. The median PLMI was 0/h, ranging from 0 to 35.5/h. Fifteen (7.7%) subjects had a PLMI > 5/h, and only 3 (1.5%) met the adult pathologic criterion of more than 15/h. Use of the 95th percentile PLMI cutoff of 7.2/h produced little difference in categorization between groups. Children with a PLMI > 5/h had a higher arousal index than those with a lower PLMI (11.6 [8.8-14.6] vs 8.1 [6.1-9.9]/h, respectively, P = 0.003). CONCLUSIONS: This study provides normative data to the field and supports the clinical periodic limb movement index cutoff of > 5/h based on both prevalence and the correlate of increased sleep fragmentation. Periodic limb movements during sleep are infrequent in normal children recruited from the community. CITATION: Marcus CL, Traylor J, Gallagher PR, Brooks LJ, Huang J, Koren D, Katz L, Mason TB, Tapia IE. Prevalence of periodic limb movements during sleep in normal children.

Relationship between sleep and pain in adolescents with juvenile primary fibromyalgia syndrome.

STUDY OBJECTIVES: To investigate sleep quality in adolescents with juvenile primary fibromyalgia syndrome (JPFS) and determine whether sleep abnormalities, including alpha-delta sleep (ADS), correlate with pain intensity. We hypothesized that successful treatment for pain with exercise therapy would reduce ADS and improve sleep quality. DESIGN: Single-center preintervention and postintervention (mean = 5.7 ± 1.0 weeks; range = 4.0-7.3 weeks) observational study. PATIENTS: Ten female adolescents (mean age = 16.2 ± 0.65 SD yr) who met criteria for JPFS and completed treatment. INTERVENTIONS: Multidisciplinary pain treatment, including intensive exercise therapy. MEASUREMENTS AND RESULTS: Pain and disability were measured by a pain visual analog scale (VAS) and the functional disability inventory. Subjective sleep measures included a sleep VAS, an energy VAS, and the School Sleep Habits Survey. Objective sleep measures included actigraphy, polysomnography (PSG), and the Multiple Sleep Latency Test. Baseline PSG was compared with that of healthy age- and sex-matched control patients. At baseline, patients had poorer sleep efficiency, more arousals/awakenings, and more ADS (70.3% of total slow wave sleep [SWS] versus 21.9% SWS, P = 0.002) than controls. ADS was unrelated to pain, disability, or subjective sleep difficulty. After treatment, pain decreased (P = 0.000) and subjective sleep quality improved (P = 0.008). Objective sleep quality, including the amount of ADS, did not change. CONCLUSIONS: Although perceived sleep quality improved in adolescents with JPFS after treatment, objective measures did not. Our findings do not suggest exercise therapy for pain improves sleep by reducing ADS, nor do they support causal relationships between ADS and chronic pain or subjective sleep quality.