Relations Between Sleep and Temperament in Preschool Children With ADHD.

Objective: The objective of this study was to assess the links between temperament and sleep in a group of preschoolers with ADHD. Method: Twenty-five ADHD (M = 5.37 years, SD = 1.09) and 22 typically developing (TD; M = 5.10, SD = 1.18) preschoolers participated in the study. Sleep was assessed with the Sleep Disturbance Scale and wrist actigraphy. The Preschool Temperament and Character Inventory (PsTCI) was used to evaluate the child temperament. Results: ADHD children showed a temperamental profile characterized by higher novelty seeking, lower persistence, self-directness, and cooperativeness and marginally lower harm avoidance (HA) compared with controls. HA was associated negatively to wakefulness after sleep onset and sleep fragmentation and positively with sleep efficiency and sleep time. Reward dependence was negatively associated with wake episode length. Conclusion: Sleep and temperament are correlated in preschoolers with ADHD and temperament might represent an intermediate endophenotype underlying the relation between ADHD and sleep disorders.

Actigraphic Sleep Pattern of Preschoolers With ADHD.

Objective: To assess the features of sleep in preschoolers with ADHD by means of questionnaire and actigraphy. Method: Twenty-five ADHD and 21 age-matched typically developing (TD) preschool children underwent the Child Behavior Checklist (CBCL) for ages 1½ to 5 and Pre-School-Age Psychiatric Assessment interview. Sleep was assessed by means of a modified Sleep Disturbance Scale for Children and wrist actigraphy for at least 5 days. Results: Children with ADHD, compared with TD, showed higher scores in CBCL Withdrawal (58.83 vs. 51.15, p < .0001), Attention Problems (69.88 vs. 51.54, p < .0001), and Aggressive Behavior (59.46 vs. 51.08, p < .0001) dimensions; they also showed increased actigraphic nocturnal activity (activity index 31.57 vs. 25.74, p < .05); and night-to-night variability for sleep minutes (56.44 vs. 32.79, p < .01), mean wake episodes (1.34 vs. 0.98, p < .05), mean activity (2.64 vs. 1.71, p < .05), and activity index (5.15 vs. 3.77, p < .05). Conclusion: This pilot study in preschoolers with ADHD showed increased motor activity during sleep and night-to-night variability for sleep duration and motor activity.

Deficient Emotional Self-Regulation in Preschoolers With ADHD: Identification, Comorbidity, and Interpersonal Functioning.

OBJECTIVE: This study aims to develop an age-adjusted Child Behavior Checklist- (CBCL) and Teacher Report Form (TRF)-based method for the detection of deficient emotional self-regulation (DESR) in preschoolers with ADHD and to assess its incidence, comorbidities, and consequences on interpersonal functioning. METHOD: Eighty-six ADHD preschoolers and 104 controls were assessed using CBCL, TRF/1½ to 5, Psychiatric Interview With Preschool Age Psychiatric Assessment, Leiter-R, and ADHD rating scales. RESULTS: Greatest sensitivity and specificity were obtained applying slightly lower threshold scores compared with school-age children (CBCL: Anxiety/Depression [A/D] ≥ 59, Attention Problems [AP] ≥ 60, Aggression Behaviors [AB] ≥ 58; TRF: A/D ≥ 59, AP ≥ 60, AB ≥ 60). DESR was detected in 33/86 (38.4%) and in 16/54 (29.6%) ADHD preschoolers versus 2/104 (1.9%) controls using CBCL and TRF, respectively. DESR is associated with significantly greater comorbidity and impairment in interpersonal functioning. CONCLUSION: Among ADHD preschoolers, DESR (a) requires lower CBCL and TRF threshold scores for detection, compared with school-age children, (b) displays similar incidence rates, and (c) is associated with enhanced psychiatric comorbidity and interpersonal difficulties.

Sleep architecture and NREM alterations in children and adolescents with Asperger syndrome.

STUDY OBJECTIVES: To analyze sleep in children with Asperger syndrome (AS) by means of standard sleep questionnaires, to evaluate sleep architecture and NREM sleep alterations by means of cyclic alternating pattern (CAP) and to correlate objective sleep parameters with cognitive behavioral measures. DESIGN: Cross-sectional study involving validated sleep questionnaires, neuropsychological scales, and PSG recording. SETTING: Sleep medicine center. PARTICIPANTS: Eight children with AS, 10 children with autism, and 12 healthy control children. INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: Children with AS had a higher prevalence of problems of initiating sleep and daytime sleepiness. Sleep architecture parameters showed minor differences between the 3 groups. CAP parameters showed an increased percentage of A1 and a decreased percentage of A2 subtypes in subjects with AS vs. controls. All A subtype indexes (number per hour of NREM sleep) were decreased, mostly in sleep stage 2 but not in SWS. With respect to children with autism, subjects with AS showed increased CAP rate in SWS and A1 percentage. In subjects with AS, verbal IQ had a significant positive correlation with total CAP rate and CAP rate in SWS and with global and SWS A1 index. The percentage of A2 negatively correlated with full scale IQ, verbal and performance IQ. CBCL total score correlated positively with CAP rate and A1 index while externalizing score correlated negatively with A3%. CONCLUSIONS: This study shows peculiar CAP modifications in children with AS and represents an attempt to correlate the quantification of sleep EEG oscillations with the degree of mental ability/disability.

Sleep cyclic alternating pattern in normal preschool-aged children.

STUDY OBJECTIVES: To evaluate the characteristics of the cyclic alternating pattern (CAP) in the sleep of preschool-aged children in order to obtain normative parameters in this age range. DESIGN: Prospective study. SETTINGS: University sleep laboratory. PARTICIPANTS: Ten normal healthy subjects (6 girls and 4 boys, mean age 4.6 years; range 3-6 years) underwent polysomnography recordings for 2 consecutive nights in a standard laboratory setting. Sleep data were stored on a computer using a polysomnography digital system (Embla N7000, Medcare, Iceland). Sleep structure was visually scored according to the Rechtschaffen and Kales criteria. The cyclic alternating pattern was visually scored following the criteria by Terzano et al. These criteria were modified for the purposes of this study because it was noticed that, at the age of the group under analysis, most electroencephalogram arousals, often accompanied by electromyogram activation, are expressed at the level of the electroencephalogram by theta frequencies and not alpha or higher frequencies. MEASUREMENTS AND RESULTS: The CAP rate in preschool-aged children (25.93%) showed a progressive increase with the deepness of sleep, with highest values during non-rapid eye movement (NREM) stage 3 (44.0%) and 4 sleep (46.08%) and lowest values in NREM stage 2 (17.26%). The CAP time showed its longest duration during stage 2 sleep, followed by stage 4, stage 3, and NREM stage 1. The CAP cycle duration showed no differences across NREM stages. The cyclic alternating pattern phase A was longer and phase B was shorter during stage 1 than during stages 2, 3, and 4. A1 phases were the most numerous (63.2%), followed by A2 (21.5%) and by A3 (15.3%). The distribution of A-phase subtypes across NREM sleep stages (A index) showed significant differences for the A1 subtypes that occurred more frequently during stage 3 and 4 sleep than during stages 1 and 2. The A2 index showed no significant differences across NREM sleep stages, while the A3 index was significantly higher during stage 1 sleep than during stages 2, 3, and 4. The analysis of the A1 interval distribution showed a log-normal-like distribution with a peak around 25 seconds for the A1 phases and no clear peak for A2-A3 phases. CONCLUSIONS: The analysis of CAP in preschool-aged children is characterized by an increase of CAP rate during slow-wave sleep and a high percentage of A1 phases and A2 phases. However, the lower percentage of A1 paralleled by an increase of A2 could represent a signal of higher sleep instability in this age group as compared with prepubertal school-aged children.

Sleep cyclic alternating pattern in normal school-age children.

OBJECTIVES: To evaluate cyclic alternating pattern (CAP) in sleep of school-age children in order to obtain a standardized database for CAP parameters in this age range. METHODS: CAP parameters were quantified in 10 normal healthy subjects (6 males and 4 females, mean age 8.3 years; range 6-10 years). All subjects underwent polysomnography recordings for two consecutive nights in a standard laboratory setting. Sleep data were stored on computer using a 16-channel polysomnography digital system. Sleep macrostructure was visually scored according to the criteria by Rechtschaffen and Kales (Brain Information Service/Brain Research Institute, University of California, Los Angeles, 1968); CAP was visually scored following the criteria by Terzano et al. (Sleep Med 2 (2001) 537). RESULTS: CAP rate showed a progressive increase with the deepness of sleep, with high values during slow wave sleep (SWS). CAP time showed its longest duration during non-REM (NREM) sleep stage 2 (S2), followed by SWS and sleep stage 1 (S1). No differences across NREM sleep stages were found for CAP cycle and phase B mean duration; on the contrary, phase A showed longer duration during SWS than in S1 and S2. Phases A1 were the most numerous (84.45%) followed by A3 (9.14%) and by A2 (6.44%). The distribution of phases A subtypes across NREM stages showed significant differences for the A1 subtypes that occurred more frequently during SWS than in S2 and S1 (and during S2 than in S1). Subtypes A3 were more frequent during S1 than SWS while no differences were found for subtype A2. The analysis of A1 interval distribution showed a log-normal-like distribution with a peak around 25 s for the A1 phases and no clear peak for A2-A3 phases. CONCLUSIONS: The analysis of CAP in school-age children is characterized by an increase of CAP rate during SWS and a high percentage of A1 phases. The distribution of interval between consecutive A1 phases showed a peak around 25 s.