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Eric Konofal

Publications and source records attributed to Eric Konofal.

13 recordsLinked to original sources

Family-based association study of the restless legs syndrome loci 2 and 3 in a European population.

Three loci for the restless legs syndrome (RLS) on chromosomes 12q, 14q, and 9p (RLS1, RLS2, and RLS3) have been mapped, but no gene has been identified as yet. RLS1 has been confirmed in families from three different populations. We conducted a family-based association study of 159 European RLS trios. The subjects were genotyped using microsatellite markers evenly covering the candidate regions on chromosomes 14q and 9p with an average intermarker distance of 1.1 cM. Transmission disequilibrium tests were used to analyze the data, and empirical P values were estimated by permutation testing. On chromosome 14q, a significant association (empirical P = 0.0033) was found with a haplotype formed by markers D14S1014 and D14S1017 when analyzing all families. On chromosome 9p, no significant association in the sample of all families and only marginally significant associations were detected, with a haplotype involving markers D9S1846-D9S171 in a subset of South European trios and with a haplotype at D9S156-D9S157 in a subset of Central European trios (P = 0.0086 and 0.0077, respectively). These results represent the first confirmation of these loci in a mixed European population. Variable results observed in families of different ethnic groups further corroborate the genetic complexity of RLS.

Chromosomes, Human, Pair 12↗

Restless legs syndrome triggered by heart surgery.

This report presents the case of a 9-year-old child with a familial history of restless legs syndrome who began to complain of restless legs syndrome symptoms after heart surgery. Hypotheses on the potential interactions between genetic and environmental factors in the development of her restless legs syndrome are discussed. Increasing evidence supports reduced brain iron in the pathophysiology of idiopathic restless legs syndrome. It is possible that the child inherited a compromised brain and peripheral iron regulation, which predisposed her to restless legs syndrome. The interaction between her dysfunctional iron management and her intraoperatory blood loss may have led to a significant decrease in brain iron, triggering restless legs syndrome symptoms. Other factors, such as immobilization and sleep deprivation after surgery, may have contributed to trigger the restless legs syndrome symptoms. If confirmed by further evidence, this patient suggests the need to carefully monitor for restless legs syndrome symptoms in young surgical patients who present with a familial history of restless legs syndrome.

Child↗

ADHD and insomnia.

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Antidepressive Agents↗

Sleep and alertness in children with attention-deficit/hyperactivity disorder: a systematic review of the literature.

STUDY OBJECTIVE: To review evidence on sleep and alertness in children with attention-deficit/hyperactivity disorder (ADHD) controlling for potential confounding factors. METHODS: A PubMed search. Studies using ADHD diagnostic criteria other than DSM-III-R or IV and studies not excluding or controlling for psychiatric comorbidity or medication status were not included in the review. Results from objective studies were combined using meta-analysis. RESULTS: From the 46 studies located, 13 were retained. With regard to objective studies, the proportion of subjects who fell asleep during the Multiple Sleep Latency Test, the number of movements in sleep, and the apnea-hypopnea index were significantly higher in children with ADHD than in controls. We found no significant differences in other objective parameters (sleep-onset latency; number of stage changes; percentages of stage 1 sleep, stage 2 sleep, slow-wave sleep, or rapid eye movement sleep; rapid eye movement sleep latency; and sleep efficiency). Limited evidence from subjective studies suggests no significant differences in sleep-onset difficulties and bedtime resistance between children with ADHD and controls, after controlling for comorbidity and medication status. Data on sleep duration, night and morning awakenings, and parasomnias are still very limited. CONCLUSION: Results from our systematic review suggest that children with ADHD have higher daytime sleepiness, more movements in sleep, and higher apnea-hypopnea indexes compared with controls. Given the limited number of studies controlling for confounding factors, further subjective and objective studies are needed to better understand alterations in sleep and alertness in children with ADHD.

Arousal↗

Restless legs syndrome and attention-deficit/hyperactivity disorder: a review of the literature.

STUDY OBJECTIVE: To review evidence on the association between restless legs syndrome (RLS) and attention-deficit/hyperactivity disorder (ADHD), to discuss the hypothetical mechanisms underlying this association, and to consider the potential interest for common pharmacologic treatments of RLS and ADHD when co-occurring. METHOD: A PubMed search. RESULTS: In clinical samples, up to 44% of subjects with ADHD have been found to have RLS or RLS symptoms, and up to 26% of subjects with RLS have been found to have ADHD or ADHD symptoms. Several mechanisms may explain this association. Sleep disruption associated with RLS might lead to inattentiveness, moodiness, and paradoxical overactivity. Diurnal manifestations of RLS, such as restlessness and inattention, might mimic ADHD symptoms. Alternatively, RLS might be comorbid with idiopathic ADHD. Subjects with RLS and a subset of subjects with ADHD might share a common dopamine dysfunction. Limited evidence suggests that some dopaminergic agents, such as levodopa/carbidopa, pergolide, and ropinirole, may be effective in children with RLS associated with ADHD symptoms. CONCLUSIONS: Although still limited, evidence from clinical studies demonstrates an association between RLS and ADHD or ADHD symptoms. Further clinical studies using standard criteria and procedures are needed to better estimate the degree of association. Epidemiologic studies are required to assess the relationship between ADHD and RLS symptoms in nonclinical samples. Further investigations should address the mechanisms underlying the relationship between RLS and ADHD. Several dopaminergic agents seem to be promising treatment for RLS associated with ADHD symptoms. To date, however, the absence of randomized and blinded controlled studies does not allow evidence-based recommendations.

Adolescent↗

Stages 1-2 non-rapid eye movement sleep behavior disorder associated with dementia: a new parasomnia?

A 55-year-old woman with a progressive dementia and frontal syndrome was hospitalized because she was agitated every night after falling asleep (spoke, laughed, cried, tapped, kicked, walked, and fell down). She slept 5.5 hours during video polysomnography, but the theta rhythm electroencephalograph recording typical of sleep stages 1 to 2 and the spindles and K-complexes typical of sleep stage 2 contrasted with continuous muscular twitching, prominent rapid eye movements, vocalizations, and continuous, complex, purposeful movements typical of rapid eye movement (REM) sleep behavior disorder. This newly described stages 1--2 non-REM sleep behavior disorder suggests that central motor pattern generators were disinhibited during non-REM sleep.

Dementia↗

Ropinirole in a child with attention-deficit hyperactivity disorder and restless legs syndrome.

A 6-year-old male being treated with limited efficacy by methylphenidate immediate release for attention-deficit hyperactivity disorder also presented with sleep disruption due to potential restless legs/periodic limb movement syndrome. Treatment with the dopamine agonist ropinirole resulted in a significant improvement in both his attention-deficit hyperactivity disorder symptoms and sleep problems.

Attention Deficit Disorder with Hyperactivity↗

Effect of genetically caused excess of brain gamma-hydroxybutyric acid and GABA on sleep.

BACKGROUND: Exogenous gamma-hydroxybutyrate (GHB) increases slow-wave sleep and reduces daytime sleepiness and cataplexy in patients with primary narcolepsy. OBJECTIVE: To examine nighttime sleep and daytime sleepiness in a 13-year-old girl homozygous for succinic semialdehyde dehydrogenase (SSADH) deficiency, a rare recessive metabolic disorder that disrupts the normal degradation of 4-aminobutyric acid (GABA), and leads to an accumulation of GHB and GABA within the brain. METHODS: Sleep interview, nighttime polysomnography, Multiple Sleep Latency Tests, and continuous 24-hour in-lab recordings in the patient; overnight polysomnography in her recessive mother and in a 13-year-old female control. RESULTS: During quiet wakefulness, background electroencephalographic activity was slow and composed of 7-Hz activity. Sleep stage 3/4 was slightly increased (28.1% of total sleep period, norms 15%-28%), and the daytime mean sleep latency was short in the patient (3 minutes 42 seconds, norms > 8 minutes). Stage 2 spindles were infrequent in the child (0.18/minute, norms: 1.2-9.2/minute) and her mother (0.65/minute) but normal (4.6/minute) in the control. At the beginning of the second night, a tonic-clonic seizure occurred, followed by a dramatic increase in stage 3/4 sleep, that lasted 46.3 % of the total sleep period, double the normal value. The mother showed a reduced total sleep time and rapid eye movement sleep percentage. DISCUSSION: This suggests that a chronic excess of GABA and GHB induces subtle sleep abnormalities, whereas increased slow-wave sleep evoked by a sudden event (here an epileptic seizure) may be caused by a supplementary increase in GABA and GHB.

Adolescent↗

Effectiveness of iron supplementation in a young child with attention-deficit/hyperactivity disorder.

A 3-year-old child was referred to consultation for hyperactivity, attention deficit, impulsivity, and sleep problems. He met Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition criteria for attention-deficit/hyperactivity disorder. At baseline, the Conners' Parent Rating Scale and the Conners' Teacher Rating Scale raw total scores were 30 and 32, respectively. The child had low a serum ferritin level (13 ng/mL). After 8 months of treatment with Tardyferon (ferrous sulfate, 80 mg/day), his serum ferritin increased to 102 ng/mL. Both parents and teachers reported considerable behavioral improvement. The Conners' Parent and Teacher Rating Scale raw total scores decreased to 19 and 13, respectively. This is the first report of the effectiveness of iron supplementation in a young child with attention-deficit/hyperactivity disorder.

Attention Deficit Disorder with Hyperactivity↗

REM sleep behavior disorder and REM sleep without atonia in patients with progressive supranuclear palsy.

STUDY OBJECTIVE: To compare sleep characteristics, rapid eye movement (REM) sleep without atonia, and REM sleep behavior disorder (RBD) in patients with progressive supranuclear palsy (tauopathy), patients with Parkinson's disease (a synucleinopathy), and control subjects. DESIGN: Sleep interview, overnight polysomnography, and Multiple Sleep Latency Tests. PATIENTS: Forty-five age- and sex-matched patients with probable progressive supranuclear palsy, (n=15, aged 68 +/- 8 years, 7 men), patients with Parkinson disease (n=15), and control subjects (n=15). SETTINGS: Tertiary-care academic hospital. INTERVENTION: N/A. RESULTS: Compared to the 2 other groups, patients with progressive supranuclear palsy had a longer duration of wakefulness after sleep onset and twice as much sleep fragmentation and percentage of stage 1 sleep but had similar apnea-hypopnea indexes, periodic leg movements indexes, and mean daytime sleep latencies. REM sleep percentage was as low in patients with progressive supranuclear palsy (8% +/- 6% of total sleep time) as in patients with Parkinson disease (10% +/- 4%), versus 20% +/- 6% in controls (analysis of variance, P < .0001). Interestingly, patients with progressive supranuclear palsy had percentages of REM sleep without atonia (chin muscle activity: 33% +/- 36% of REM sleep) similar to those of patients with Parkinson disease (28% +/- 35%) and dramatically higher than those of controls (0.5% +/- 1%, analysis of variance, P = .008). Four (27%) patients with progressive supranuclear palsy had more than 50% REM sleep without atonia (as did a similar number of patients with Parkinson disease), and 2 of them (13%, vs 20% of patients with Parkinson disease) had clinical RBD. The four patients with progressive supranuclear palsy with excessive daytime sleepiness slept longer at night than the 11 patients with progressive supranuclear palsy who were alert (442 +/- 14 minutes vs 312 +/- 74 minutes, student t tests, P = .004), suggesting a primary nonnarcoleptic hypersomnia. CONCLUSION: REM sleep without atonia and RBD were as frequent in patients with progressive supranuclear palsy as in patients with Parkinson disease. It suggests that the downstream cause of parkinsonism, rather than its primary neuropathology (synucleinopathy vs tauopathy), is a key factor for REM sleep behavior disorder.

Aged↗

Iron deficiency in children with attention-deficit/hyperactivity disorder.

BACKGROUND: Iron deficiency causes abnormal dopaminergic neurotransmission and may contribute to the physiopathology of attention-deficit/hyperactivity disorder (ADHD). OBJECTIVE: To evaluate iron deficiency in children with ADHD vs iron deficiency in an age- and sex-matched control group. DESIGN: Controlled group comparison study. SETTING: Child and Adolescent Psychopathology Department in European Pediatric Hospital, Paris, France. PATIENTS: Fifty-three children with ADHD aged 4 to 14 years (mean +/- SD, 9.2 +/- 2.2 years) and 27 controls (mean +/- SD, 9.5 +/- 2.8 years). MAIN OUTCOME MEASURES: Serum ferritin levels evaluating iron stores and Conners' Parent Rating Scale scores measuring severity of ADHD symptoms have been obtained. RESULTS: The mean serum ferritin levels were lower in the children with ADHD (mean +/- SD, 23 +/- 13 ng/mL) than in the controls (mean +/- SD, 44 +/- 22 ng/mL; P < .001). Serum ferritin levels were abnormal (<30 ng/mL) in 84% of children with ADHD and 18% of controls (P < .001). In addition, low serum ferritin levels were correlated with more severe general ADHD symptoms measured with Conners' Parent Rating Scale (Pearson correlation coefficient, r = -0.34; P < .02) and greater cognitive deficits (r = -0.38; P < .01). CONCLUSIONS: These results suggest that low iron stores contribute to ADHD and that ADHD children may benefit from iron supplementation.

Adolescent↗

[Sleep and vigilance in hyperactive children].

Inattention, impulsiveness and hyperactivity are the main clinical features that characterise the attention deficit hyperactivity disorder (ADHD). Children with ADHD essentially present with diurnal manifestations but studies have recently shown a link between sleep and daytime symptoms. ADHD children could present sleep problems such as agitated sleep, sleep-onset difficulties, low arousal threshold during the night. Such sleep difficulties have been shown to occur more frequently in children with severe diurnal ADHD symptoms. Sleep studies using polysomnography have been performed in children with ADHD. Abnormalities during sleep such as increased motricity could be responsible for hypovigilance as measured using multiple sleep latency tests. Prevalence and physiopathology of sleep disorders including awakening mechanisms (micro-arousals, arousal threshold) from sleep yet need to be clarified in ADHD children. Understanding the mechanisms governing the sleep-wake balance seems essential for the comprehension of ADHD. Excessive nocturnal motricity could be the expression of a monoaminergic dysfunctioning previously reported in ADHD and could lead to new therapeutic gateways as well as hypovigilance.

Attention↗