The prevalence of pediatric obstructive sleep apnea syndrome (OSAS) is approximately 3% in children. Adenotonsillar hypertrophy is the most common cause of OSAS in children, and obesity, hypotonic neuromuscular diseases, and craniofacial anomalies are other major risk factors. Snoring is the most common presenting complaint in children with OSAS, but the clinical presentation varies according to age. Agitated sleep with frequent postural changes, excessive sweating, or abnormal sleep positions such as hyperextension of neck or abnormal prone position may suggest a sleep-disordered breathing. Night terror, sleepwalking, and enuresis are frequently associated, during slow-wave sleep, with sleep-disordered breathing. Excessive daytime sleepiness becomes apparent in older children, whereas hyperactivity or inattention is usually predominant in younger children. Morning headache and poor appetite may also be present. As the cortical arousal threshold is higher in children, arousals are not easily developed and their sleep architectures are usually more conserved than those of adults. Untreated OSAS in children may result in various problems such as cognitive deficits, attention deficit/hyperactivity disorder, poor academic achievement, and emotional instability. Mild pulmonary hypertension is not uncommon. Rarely, cardiovascular complications such as cor pulmonale, heart failure, and systemic hypertension may develop in untreated cases. Failure to thrive and delayed development are serious problems in younger children with OSAS. Diagnosis of pediatric OSAS should be based on snoring, relevant history of sleep disruption, findings of any narrow or collapsible portions of upper airway, and confirmed by polysomnography. Early diagnosis of pediatric OSAS is critical to prevent complications with appropriate interventions.

Korean adolescents have severe nighttime sleep deprivation and daytime sleepiness because of their competitive educational environment. However, daytime sleep patterns and sleepiness have never been studied using age-specific methods, such as the pediatric daytime sleepiness scale (PDSS). We surveyed the daytime sleepiness of Korean adolescents using a Korean translation of the PDSS. We distributed the 27-item questionnaire, including the PDSS and questions related to sleep pattern, sleep satisfaction, and emotional state, to 3,370 students in grades 5-12. The amount of nighttime sleep decreased significantly with increasing age. During weekday nights, 5-6(th) graders slept for 7.95±1.05 h, 7-9(th) graders for 7.57±1.05 h, and 10-12(th) graders for 5.78±1.13 h. However, the total amounts of combined daytime and nighttime sleep during weekdays were somewhat greater, 8.15±1.12 h for 5-6(th) graders, 8.17±1.20 h for 7-9(th) graders, and 6.87±1.40 h for 10-12(th) graders. PDSS scores increased with age, 11.89±5.56 for 5-6(th) graders, 16.57±5.57 for 7-9(th) graders, and 17.71±5.24 for 10-12(th) graders. Higher PDSS scores were positively correlated with poor school performance and emotional instability. Korean teenagers sleep to an unusual extent during the day because of nighttime sleep deprivation. This negatively affects school performance and emotional stability. A Korean translation of the PDSS was effective in evaluating the severity of daytime sleepiness and assessing the emotional state and school performance of Korean teenagers.

Delaying the time of start of school allows for longer sleep duration, better mood, and better school performance. In South Korea, a campaign was launched in 2014 to delay the school start time to 9 a.m. We analyzed the campaign’s effects on adolescents’ total sleep duration, sleepiness (presented as weekend catch-up sleep), emotions, and school performance. Based on data from 2013, changes of sleep patterns, emotions, and academic achievement in adolescents were evaluated using the 2012–2016 Korea Youth Risk Behavior Web-based survey from two educational districts: Gyeonggi (fully participated in the delayed school start time campaign; intervention group) and Daegu/Gyeongbuk/Ulsan (DGU, never participated; control group). The primary outcomes were sleep duration, time of sleep onset, and difference in sleep duration between weekdays and the weekend. Secondary outcomes were the proportional changes of mood, stress, and school performance. The sleep duration of students in the intervention group temporarily increased in 2015. However, because there was a simultaneous delay in time of sleep onset, sleep duration returned to pre-campaign levels in 2016. Although sleep duration did not increase, weekend catch-up sleep decreased by approximately 19 minutes for students in the intervention group. Meanwhile, in the control group sleep duration tended to decrease over the same period. The impact of the campaign on students' emotions and school performance could not be confirmed. This study demonstrated that delaying the school start time to 9 a.m. reduced duration of weekend catch-up sleep with a transient increase in sleep duration in adolescents.

Background: Congenital muscular torticollis (CMT) is a common musculoskeletal disorder occurring at birth or in infancy.Purpose: This study aimed to investigate the risk of comorbidities in CMT and explore the differences in neurodevelopmental outcomes between children who received physical therapy and those who did not.Methods: Children with CMT born in 2008 and 2009 in Korea were included. CMT was defined as a primary diagnosis of congenital deformity of sternocleidomastoid muscle according to the International Classification of Diseases 10th revision. Here we investigated the associated neurological/musculoskeletal comorbidities of children with CMT versus those of the general population. We divided those with torticollis into treatment and nontreatment groups and assessed their developmental outcomes within both groups of children using the Korean-Ages and Stages Questionnaire (K-ASQ).Results: Of the 917,707 children, 0.2% (n=1,719) were diagnosed with CMT. In children with torticollis, the prevalence of congenital hip deformities significantly increased to 4.5% (n=78). The prevalence of congenital head/spine deformities and other congenital malformations of the skull and facial bones increased to 2.6% (n=44), while the prevalence of congenital foot deformities was 2.4% (n=42). The risk ratio (RR) for delayed development based on the K-ASQ was higher for the total assessment (adjusted RR=0.97; 95% confidence interval, 0.93–0.99) in the CMT patients without physical therapy than in those with therapy. There was no significant intergroup difference in the assessment of each developmental area.Conclusion: The prevalence of comorbid musculoskeletal deformities was higher in children with CMT than in the control group. The risk of developmental delay was higher in children who did not receive physical therapy than in those who did.

Background: The use of helmet treatment for positional plagiocephaly has increased recently; however, its effect is unknown in Korea.Purpose: This study aimed to investigate the effectiveness of helmet therapy and identify its influencing factors.Methods: Ninety pediatric patients diagnosed with moderate to severe positional plagiocephaly received helmet therapy. Severity of moderate to severe positional plagiocephaly was defined as cranial vault asymmetry (CVA) >10 mm or CVA index (CVAI) >6%. Patients were categorized by age, severity, and daily helmet wear. Multiple regression analysis controlled for factors like sex and prematurity. Treatment success was assessed by comparing pre/post-helmet theray CVA and CVAI, considering normalization or decrease to mild plagiocephaly (CVA ≤10 mm or CVAI ≤6%).Results: A total of 90 participants were enrolled (mean age, 5.6±1.6 months; male, 53 [58.9%]). The mean helmet therapy duration was 6.4±2.7 months, while the mean daily wear time was 18.4±2.7 hours. Among the 90 patients, 66 (73.3%) had moderate disease and 24 (26.7%) had severe disease. The mean CVA and CVAI decreased by 6.3±2.7 mm and 4.3%±1.8% after versus before treatment (P<0.001). Treatment was successful in 76 infants (84.4%). The most effective changes in CVA and CVAI were noted in those who began treatment before 9 months of age (6.2±2.5 mm and 5.0%±1.9%, P<0.001), had high compliance (6.2±2.4 mm and 4.9%±1.9%, P<0.001), and had high severity (8.0±2.3 mm and 6.6%±1.7%, P<0.001).Conclusion: Starting helmet treatment before 9 months and wearing it over 15 hours daily yielded better outcomes.