Leg movements and periodic leg movements during sleep in the development across childhood and adolescence from 1 to 18 years.

OBJECTIVE: Age specific reference values of leg movements (LMS) and periodic leg movements (PLMS) in sleep considering their true periodicity to evaluate sleep pathologies, especially possible childhood RLS or PLMD. METHODS: In a prospective first night study of 52 healthy children/adolescents divided into six age groups from 1 to 18 years, polysomnographies were conducted and scored considering AASM rules. The frequency of LMS and PLMS were evaluated for NREM, REM, total sleep time (TST), including attention to time structure (inter-leg movement intervals, time distribution during the night) and periodicity of LMS. RESULTS: LMS and PLMS decreased with increasing age (P < 0.05). Children and adolescents older than 10 years had a PLMS index less than 5/h TST, in younger children the PLMS index was higher; 34.7% of total LMS and PLMS were accompanied by an EEG-arousal without age dependence. Periodicity index was low (median 0.2 decreasing with age to 0.1). Inter-leg movement intervals showed a decreasing incidence of shorter intervals with age. The course of LMS during the night displayed a lack of clear structure of distribution. CONCLUSIONS: To evaluate pediatric motoric sleep disturbances it is necessary to consider the age dependence of LMS/PLMS and their true periodicity.

Normative values of polysomnographic parameters in childhood and adolescence: arousal events.

OBJECTIVE: This study focused on differences in arousals during sleep, using the arousal rules of the American Academy of Sleep Medicine, by gender, age, and maturity in healthy children. METHODS: One-night polysomnography was performed on 209 healthy German children (age 1-18 years) at their habitual bedtimes in 16 laboratories. Subjects were grouped by gender (112 females, 97 males), age, and Tanner stage. RESULTS: Normative values of arousal events in sleep are presented, including indexes of spontaneous and respiratory arousals, total electroencephalogram (EEG) arousals, phasic increase in submental electromyogram (EMG) in stage R, and leg movements. With increasing age, a decrease was seen in: EEG arousal index ≥1-2.9 s, EEG arousal index ≥3 s, index of total EEG arousals, index of respiratory arousals, chin EMG enhancement in stage R ≥1-2.9 and ≥3 s, index of total leg movements, and leg movements with EEG arousals (p<0.05). Only spontaneous arousals showed no association with age. There was a significant negative correlation between Tanner stage and arousals ≥1-2.9 s, respiratory arousals, leg movements, and leg movements with arousals (p<0.05). Only arousals ≥3 s and total leg movements showed gender differences (p<0.05). CONCLUSIONS: For the diagnosis of pediatric sleep disturbances, the given arousal data enable estimation of the degree of deviation from normal findings for age and maturity. There is need for further research on, and further discussion of, the arousal rules of the American Academy of Sleep Medicine.

Normative values of polysomnographic parameters in childhood and adolescence: cardiorespiratory parameters.

OBJECTIVE: To provide normative values for pediatric sleep cardiorespiratory parameters following AASM rules, assessing effects of gender, age, and Tanner stage. METHODS: One-night polysomnograhy was performed at subjects' habitual bedtimes in 16 laboratories on 209 healthy German children, 1-18 years old. RESULTS: Normative values of cardiorespiratory parameters in pediatric sleep are presented. No obstructive and mixed apneas occurred. Hypopneas were seldom. Respiratory frequency and apnea-hypopnea-index decreased with age (p<0.001). In all groups central apneas ≥ 20 s were present but uncommon. Oxygen desaturations or respiratory arousals following central apnea were rare. Heart rate showed an inverse correlation to age (p<0.001). Heart rate was lower in sleep, lowest in stage N. The mean heart rate of females was higher than males (p<0.05). Neither Tanner stage nor corresponding age (p<0.05) influenced: mean apnea duration, central apnea index ≥ 20 s, hypopnea index, index of periodic breathing, or oxygen saturation nadir. All other parameters except maximal apnea duration and central apnea index after movements with oxygen desaturation show dependency on both Tanner stage and corresponding age (p<0.05). CONCLUSIONS: Using AASM rules, the development of cardiorespiratory parameters in healthy children, ages 1-18 is shown. Age-related norms may improve sleep pathology identification.

Normative values of polysomnographic parameters in childhood and adolescence: quantitative sleep parameters.

OBJECTIVE: To provide normative values for sleep macroarchitecture of healthy children aged 1-18 years using the AASM sleep scoring criteria, assessing the effects of gender, age, and Tanner pubertal stage. METHODS: One-night polysomnography was performed at subjects' habitual bedtimes in 16 laboratories on 209 healthy German children. RESULTS: Normal values of sleep macrostructure show significant age dependencies (p<0.05). Increasing with age: awakening index, R latency (RL), sleep efficiency (SE) (total sleep time (TST)/sleep period time (SPT)) and SE (TST/time in bed), stage N2, mean sleep cycle duration, number of stage shifts. Decreasing with age: TST, SPT, wake after sleep onset, stage N3, stage R, movement time (MT), number of sleep cycles. The following sleep parameters show a dependency on Tanner stages as well as corresponding age (p<0.05):TST, SPT, awakening index, R latency, stage N2, stage N3, MT, number of sleep cycles, mean sleep cycle duration. No gender dependencies were found. CONCLUSION: The given study, considering AASM rules, shows the development of sleep in normal children ages 1-18. Subject selection criteria and other factors influencing sleep as well AASM guideline modifications including scoring arousals in N2 and scoring MT as a measure of sleep fragmentation are discussed.

Characteristics of Sleep-Related Obstructive Respiratory Disturbances in Childhood.

Sleep-related obstructive respiratory disturbances in childhood differ significantly from the adult's obstructive sleep apnea syndrome (OSAS). In contrast to adults, in children with OSAS the disturbance of the macrostructure of sleep, the increase of the number of apneas and hypopneas, and the diminution of oxygen saturation are not so prominent. Restlessness of the sleep, as reflected by movement arousals together with cortical (electroencephalograph-recorded) arousals, is important. The combination of clinical symptoms and polysomnographic parameters is necessary to diagnose OSAS in children.