Iva Prihodova

Sleep disorders and daytime sleepiness in children with attention-deficit/hyperactivity disorder: A two-night polysomnographic study with a multiple sleep latency test

OBJECTIVEnTo evaluate sleep macrostructure, sleep disorders incidence and daytime sleepiness in attention-deficit/hyperactivity disorder (ADHD) affected children compared with controls.nnnMETHODSnThirty-one patients (26 boys, 5 girls, mean age 9.3±1.7, age range 6-12 years) with ADHD diagnosed according to DSM-IV criteria, without comorbid psychiatric or other disorders, as never before pharmacologically treated for ADHD. The controls were 26 age- and sex-matched children (22 boys, 4 girls, age range 6-12 years, mean age 9.2±1.5). Nocturnal polysomnography (PSG) was performed for two nights followed by the multiple sleep latency test (MSLT).nnnRESULTSnNo differences between the two groups comparing both nights were found in the basic sleep macrostructure parameters or in the time (duration) of sleep onset. A first-night effect on sleep variables was apparent in the ADHD group. Occurrence of sleep disorders (sleep-disordered breathing [SDB], periodic limb movements in sleep [PLMS], parasomnias) did not show any significant differences between the investigated groups. A statistically significant difference (p=0.015) was found in the trend of the periodic limb movement index (PLMI) between two nights (a decrease of PLMI in the ADHD group and an increase of PLMI in the control group during the second night). While the mean sleep latency in the MSLT was comparable in both groups, children with ADHD showed significant (sleep latency) inter-test differences (between tests 1 and 2, 1 and 4, 1 and 5, p<0.01).nnnCONCLUSIONnAfter the inclusion of adaptation night and exclusion of psychiatric comorbidities, PSG showed no changes in basic sleep parameters or sleep timing, or in the frequency of sleep disorders (SDB, PLMS) in children with ADHD compared with controls, thus not supporting the hypothesis that specific changes in the sleep macrostructure and sleep disturbances are connected with ADHD. A first-night effect on sleep variables was apparent only in the ADHD group. Though we found no proof of increased daytime sleepiness in children with ADHD against the controls, we did find significant vigilance variability during MSLT in the ADHD group, possibly a sign of dysregulated arousal.

Narcolepsy: clinical differences and association with other sleep disorders in different age groups

Narcolepsy-cataplexy (N-C) is a focal neurodegenerative disease with a genetic predisposition and autoimmune etiology; the pathogenesis of narcolepsy without cataplexy (Nw/oC) is less clear. One hundred and forty eight patients underwent clinical face-to face interviews, polysomnography, multiple sleep latency testing and HLA-DQB1*0602 typing. The cohort was divided into four age groups: children and adolescents under 19xa0years (Nxa0=xa031), adults aged 20–39xa0years (Nxa0=xa051), 40–59xa0years (Nxa0=xa028) and over 60xa0years (Nxa0=xa038). N-C was found in 93 adults (79.5xa0%) compared with 16 pediatric patients (51.6xa0%) (pxa0<xa00.01), suggesting that at least some of the children were candidates for developing cataplexy in the future. Statistical evaluation showed an increasing age-related proportion of associated sleep disorders—obstructive sleep apnea, periodic leg movements and restless leg syndrome (pxa0<xa00.001). Nw/oC patients showed sleep comorbidities less frequently than N-C group. A close connection with N-C was found particularly in REM behavior disorder (RBD) (pxa0<xa00.05). RBD affected a third of the patients in the youngest as well as in the oldest groups. However, association with other sleep disorders had no significant effect on nocturnal sleep (with the exception of obstructive sleep apnea), and the sleep comorbidities under study had no noticeable effect on daytime sleepiness.

Clinical features of childhood narcolepsy. Can cataplexy be foretold

BACKGROUNDnNarcolepsy is a life-long disease characterized by abnormal regulation of the sleep-wake cycle and increased penetration of rapid eye movement (REM) sleep. In children, narcolepsy without cataplexy is more frequently seen than in adults. The aim of our study was to evaluate clinical and polysomnographic parameters to verify if cataplexy appearing later in life can be foretold.nnnMETHODSn30 patients (12 boys), who contracted narcolepsy before the age of 18, were enrolled. All underwent clinical examination, nocturnal polysomnography (PSG), multiple sleep latency test (MSLT), HLA-DQB1∗0602 testing and, most of them Epworth Sleepiness Scale (ESS) rating. The Mann-Whitney rank and Fishers tests were used for statistical analysis.nnnRESULTSnNarcolepsy without cataplexy (NwC) was diagnosed in 40% of the patients. The mean age at the first symptoms was 14.0 ± 3.0, at diagnosis 15.6 ± 3.1 years. Narcolepsy was accompanied by hypnagogic hallucinations in 15 and sleep paralysis in 12 patients. Frequent symptoms were sleep inertia during awakening, REM behavior symptoms, behavioral and serious school problems. BMI was higher in patients with narcolepsy-cataplexy (N-C). A high ESS score was indicative of excessive daytime sleepiness (17.1 ± 2.5). Mean MSLT sleep latency was 4.0 ± 3.1 min with 3.2 ± 1.4 sleep onset REM periods (SOREMs) with no difference between the two study groups. HLA typing revealed no differences either. The N-C group showed a higher degree of wakefulness and superficial non-REM (NREM) stage 1 with a lower NREM stage 3 during PSG.nnnCONCLUSIONnNarcolepsy in childhood leaves very little scope for the prediction of cataplexy later in life.

Arousals in nocturnal groaning

BACKGROUND AND OBJECTIVEnNocturnal groaning (catathrenia) is a chronic sleep disorder classified as parasomnia with unclear effects on sleep and life quality. It is characterized by repeated episodes of monotonous vocalization in prolonged expiration (episodes of bradypnea) occurring mostly in REM sleep. We sought to assess its impact on sleep microstructure, i.e., the frequency of arousals relative to the groaning episodes. The frequency, duration and sleep-stage distribution of the groaning episodes were also studied.nnnMETHODSnEight patients with nocturnal groaning (5 male, 3 female, age range 11-32 years, mean age 23+/-7.1) were evaluated. All underwent standard neurologic examination and nocturnal videopolysomnography for two consecutive nights. The second night polysomnography data were used to evaluate sleep parameters. The groaning episodes (bradypneic events) were counted separately, not as clusters.nnnRESULTSnSleep macrostructure revealed no specific changes. The number of groaning episodes/bradypneic events during the night varied from 40 to 182 (total number 725). The duration of bradypnea was from 2 to 46s (mean duration 12.5s). Groaning episodes prevailed in REM sleep (76.5%). The rate for NREM 2 was 21.5%, and only sporadic episodes were noted in delta sleep (1.9%); 63.3% of the events were associated with arousals, and in 94% of them an arousal occurred before or together with the onset of bradypnea. The arousal index was increased in 5 patients (mean 20.4). Bruxism was present in 4 cases, in 1 patient appearing in close association with groaning episodes. Ronchopathy was noted in 4 cases.nnnCONCLUSIONnAlmost two-thirds of the groaning episodes were connected with arousals. Hypothetically, nocturnal groaning may well be a source of sleep disruption (mainly REM) in some cases. Because an arousal mostly preceded or coincided with groaning we believe that arousal mechanisms may be involved in the pathogenesis of nocturnal groaning.

Childhood parasomnia – A disorder of sleep maturation?

BACKGROUNDnChildhood parasomnias are believed to be a benign disorder due to immaturity of some neural circuits, synapses and receptors. The aim of our study was to explore a possible connection with other neurological developmental disorders.nnnMETHODSn72 children (mean age 9.9 ± 5.0 years, 47 boys) were clinically examined and 88 nocturnal v-PSG and 22 v-EEG recordings were evaluated. The most frequent diagnostic findings were: sleepwalking in 24 children, confusional arousal in 21, sleep terror in 8, groaning and enuresis each in 7, non-specific arousal disorder in 4 patients, and REM-related parasomnia in only one child. For statistical evaluation chi-square test, the two-sample t-test and Mann-Whitney rank test were used.nnnRESULTSnPerinatal risk history was found in 38% of the cohort. Developmental disorders were diagnosed in 30 children (41.7%), more frequently in combinations with: attention-hyperactivity disorder (30.6%), dyslexia and dysgraphia (13.9%), developmental dysphasia (9.7%), mild motor and/or intellectual dysfunction (6.9%). Abnormal movements in sleep, some of them also regarded as developmental, were diagnosed in 37 children (51.4%). Sleep-related breathing disorders were found in 29 patients (40.3%) -snoring (29.2%) and/or sleep apnea (11.1%). Only 16.7% had no comorbidity. Most of the children (60%) showed 2 or 3, exceptionally up to 5 comorbidities. Children, in whom no parasomnia was found in close relatives, had a mild but non-significant earlier onset of the disease (4.4 ± 4.0 against 6.3 ± 4.3 years).nnnCONCLUSIONnChildhood parasomnias are frequently associated with perinatal risk factors and developmental comorbidities, and can be regarded as a disorder of sleep maturation.

Childhood narcolepsy and autism spectrum disorders: four case reports

BACKGROUNDnChildhood narcolepsy is associated with various emotional, behavioural and cognitive dysfunctions as well as with psychiatric and neurodevelopmental disorders: anxiety, depression, attention deficit hyperactivity disorder and psychosis. A relationship between these conditions is unclear - comorbidity or similar pathophysiological mechanisms can be suggested.nnnOBJECTIVEnWe reported four children with narcolepsy type 1 (NT1) and autism spectrum disorder (ASD) - Asperger syndrome (AS).nnnRESULTS AND CONCLUSIONnTo the best of our knowledge co-occurrence of NT1 and AS has not been described in the literature as noted in this report.