Validation of Fitbit Charge 2 and Fitbit Alta HR Against Polysomnography for Assessing Sleep in Adults With Obstructive Sleep Apnea.

STUDY OBJECTIVES: Consumer wearable devices may be a helpful method of assessing sleep, but validation is required for their use in clinical practice. Our aim was to validate two models of Fitbit sleep trackers that rely on both accelerometer and heart rate sensors against polysomnography in participants with obstructive sleep apnea (OSA). METHODS: Participants were adults presenting with symptoms of OSA and attending our outpatient sleep clinic. A polysomnography (PSG) was applied to all participants at the same time they were wearing a Fitbit sleep tracker. Using paired t tests and Bland-Altman plots, we compared the sleep measures provided by the wearable devices with those obtained by PSG. Since Fitbit devices' automatic detection of sleep start time can cause bias, we performed a correction using Huber loss function-based linear regression and a leave-one-out strategy. RESULTS: Our sample consisted of 65 patients. Diagnosis of OSA was confirmed on 55 (84.6%). There were statistically significant differences between PSG and Fitbit measures for all sleep outcomes but rapid eye movement sleep. Fitbit devices overestimated total sleep time, and underestimated wake after sleep onset and sleep onset latency. After correction of bias, Fitbit-delivered measures of sleep onset latency did not significantly differ of those provided by PSG. CONCLUSIONS: Fitbit wearable devices showed an acceptable sensitivity but poor specificity. Consumer sleep trackers still have insufficient accuracy for clinical settings, especially in clinical populations. Solving technical issues and optimizing clinically-oriented features could make them apt for their use in clinical practice in a nondistant future.

Contribution of sleep deprivation to suicidal behaviour: A systematic review.

Sleep disturbances and suicidal behaviour are highly prevalent phenomena, representing with a significant burden to society. Sleep has been acknowledged as a potential biomarker for suicidal behaviour. Over the past decade several studies have explored the association between sleep problems and suicidal behaviour. This area has attracted a growing research interest, hence updated information is needed. We therefore present a wide-scope review of the literature summarizing the most relevant studies on epidemiological and theoretical issues underlying this association. Implications of these findings for clinical practice and future research are discussed. We performed a systematic search of PubMed and Embase databases up to October 2018 to identify studies exploring the association between sleep and suicide. Sixty-five articles met the selection criteria, thus they were included in the review. There was a significant and independent association between sleep disturbances and suicide risk. Psychiatric disorders, sleep deprivation-induced neurocognitive deficits, emotional dysregulation, alterations in circadian rhythms, and negative feelings, among other factors, contributed to this relationship. Sleep loss may lead to higher levels of impulsivity, thus increasing unplanned suicidal behaviour. Sleep disturbances may therefore predict suicidal behaviour, hence becoming a potential therapeutic target.

Criterios neurofisiológicos en el síndrome de Guillain-Barré infantil. Ocho años de experiencia / Electrodiagnostic criteria for childhood Guillain-Barré syndrome. Eight years’ experience

Introducción. El síndrome de Guillain-Barré es la causa más frecuente de parálisis flácida aguda en niños. Los criterios diagnósticos difieren según el subtipo, desmielinizante o axonal; y la prevalencia, por área geográfica. El estudio electromiográfico permite identificar variantes, valorar el pronóstico y predecir la evolución; es, además, una herramienta objetiva para el seguimiento. Objetivo. Describir las características electromiográficas de los casos de síndrome de Guillain-Barré valorados en el hospital y su clasificación por patrón fisiopatológico. Pacientes y métodos. Se incluyen todos los casos diagnosticados entre los años 2005 y 2012. Se realizaron estudios de conducción nerviosa motora y sensitiva y ondas F, en 14 niñas y 11 niños, entre 1 y 13 años de edad. Resultados. Se diagnosticaron 19 casos de polineuropatía desmielinizante inflamatoria aguda (AIDP) y cinco de neuropatía axonal motora aguda (AMAN). El electromiograma se realizó entre los días 1 y 30 tras el inicio de los síntomas. En los casos de AIDP, se objetivó desmielinización multifocal, cuatro de ellos con el sural preservado y 13 con alteración o ausencia de la onda F. En los casos de AMAN, cuatro tenían potenciales de baja amplitud y en uno no se evocaban. Conclusiones. La forma desmielinizante de la enfermedad es la más frecuente, aunque destaca el elevado número de casos de AMAN, en probable relación con la población objeto de estudio. La evolución fue favorable en tres casos de neuropatía axonal motora y en 15 de polineuropatía desmielinizante aguda. En cuatro casos se cronificaron los síntomas, tres de ellos con desmielinización persistente, hallazgo similar al de otros estudios en niños (AU)

Introduction. The Guillan-Barré syndrome is the most frequent case of acute flacid paralysis in children. The diagnostic criteria differ according to the demyelinating or axonal variant and the prevalence by geographical area. The electromyographic study permits identifying variants, evaluating the prognosis and predicting the evolution, is in addition an objective tool for the monitoring. Aim. To describe the electromyographic characteristics of the Guillain-Barré syndrome evaluated in hospital and its classification by physiopathological pattern. Patients and methods. All the cases diagnosed between 2005 and 2012 are included. Studies of motor and sensitive nervous conduction and F waves in 14 girls and 11 boys between 1 and 13 years of age. Results. 19 cases of acute inflammatory demyelinating polyneuropathy (AIDP) and five of acute motor axonal neuropathy (AMAN) were diagnosed. The electromyogram was performed between 1 and 30 days after the beginning of symptoms. In AIDP cases, multifocal demyelination, four of them with the preserved sural and 13 with alteration and absence of F wave were objectified. In the cases of AMAN, four had low amplitude potential and in one of them they were not evoked. Conclusions. The demyelinating form of the illness is the most frequent although the high number of AMAN cases stands out, probably related to the population object of study. The evolution was favorable in three cases of motor axonal neuropathy and in 15 accute demyelinating polyneuropathy. In four cases the symptoms became chronic; three of them with persistent demyelination a similar occurrence in other studies with children (AU)

[Electrodiagnostic criteria for childhood Guillain-Barre syndrome. Eight years' experience]. / Criterios neurofisiologicos en el sindrome de Guillain-Barre infantil. Ocho anos de experiencia.

INTRODUCTION. The Guillan-Barre syndrome is the most frequent case of acute flacid paralysis in children. The diagnostic criteria differ according to the demyelinating or axonal variant and the prevalence by geographical area. The electro-myographic study permits identifying variants, evaluating the prognosis and predicting the evolution, is in addition an objective tool for the monitoring. AIM. To describe the electromyographic characteristics of the Guillain-Barre syndrome evaluated in hospital and its classification by physiopathological pattern. PATIENTS AND METHODS. All the cases diagnosed between 2005 and 2012 are included. Studies of motor and sensitive nervous conduction and F waves in 14 girls and 11 boys between 1 and 13 years of age. RESULTS. 19 cases of acute inflammatory demyelinating polyneuropathy (AIDP) and five of acute motor axonal neuropathy (AMAN) were diagnosed. The electromyogram was performed between 1 and 30 days after the beginning of symptoms. In AIDP cases, multifocal demyelination, four of them with the preserved sural and 13 with alteration and absence of F wave were objectified. In the cases of AMAN, four had low amplitude potential and in one of them they were not evoked. CONCLUSIONS. The demyelinating form of the illness is the most frequent although the high number of AMAN cases stands out, probably related to the population object of study. The evolution was favorable in three cases of motor axonal neuropathy and in 15 accute demyelinating polyneuropathy. In four cases the symptoms became chronic; three of them with persistent demyelination a similar occurrence in other studies with children.

Clinical, polysomnographic and laboratory characteristics of narcolepsy-cataplexy in a sample of children and adolescents.

OBJECTIVE: To report our findings from a sample of narcoleptic children and adolescents evaluated in our unit from 1988 to 2005. PATIENTS AND METHODS: The sample was composed of nine children (5 boys) with a mean age of 14.5 years at diagnosis. The protocol included the following: Epworth, Ullanlinna narcolepsy scale, and Stanford cataplexy questionnaires; physical, psychological and neurological examinations; neuroimaging; PSG+MSLT recordings; HLA and in two cases Hcrt-1 level in CSF. RESULTS: Narcolepsy was sporadic in all cases. The first symptom was EDS with a mean age at onset of 9.4±2.5 years (range 6-13 years). All patients complained of cataplexy. Other symptoms were hypnagogic hallucinations (4 children) and sleep paralysis (3 children). All the children performed poorly at school, 4 had emotional disorders with depression, 4 displayed nocturnal eating and weight gain. Mean BMI was 25.0 kg/m(2). One girl was diagnosed as having precocious puberty, polycystic ovary syndrome (PCOS), hyperandrogenism and insulin resistance. The MRI showed a partial empty sella. Hcrt-1 was undetectable in her CSF. The mean Ullanlinna score was 24.6; PSG showed disturbed nocturnal sleep and the MSLT showed a mean sleep latency of 2.1 min and 3 SOREMPs. Eight children were DR2-DQ1-positive, whereas one boy was DR2-negative but DQ1-positive. In two patients, Hcrt-1 was undetectable. All children, in addition to scheduled naps during the day, were treated with modafinil or methylphenidate combined with an antidepressant and in two cases with sodium oxybate. CONCLUSION: NC was sporadic in all children and associated with precocious puberty and PCOS, hyperandrogenism and insulin resistance in one case. EDS, cataplexy, disturbed nocturnal sleep, nocturnal eating, poor school performance, and emotional disorders were the principal complaints. All patients had DQB1∗0602 and Hcrt-1 was evaluated in two cases (undetectable in both).

Epileptic nystagmus: a case study video-EEG correlation.

Epileptic nystagmus (EN) is an uncommon phenomenon characterized by repetitive and rapid saccades, in association with epileptic discharges. We present a critical video-EEG recording in a patient with occipital seizures that appeared clinically as EN. The subject, male, 70 years-old, was examined because of generalized tonic-clonic seizures, preceded by left cephalic version. These were controlled using i.v. PHT, but partial seizures persisted, which we recorded using video-EEG. Clinically, we observed episodes of left conjugate deviation of the eyes, accompanied by horizontal nystagmoid movements, with a rapid leftward component and visual hallucinations. The patient did not lose consciousness. Ictal EEG: spike rhythm in the posterior right occipito-temporal region extending to adjacent and contralateral regions, followed by post-discharge of slow waves. The video-EEG was interpreted as partial oculo-clonic status epilepticus of right temporo-occipital origin. Cranial MRI: old, bilateral hemorrhaging occipital contusions associated with previous cranial injury. The picture persisted for two days, and disappeared with administration of CBZ 600 mg/d. Our patient's nystagmus seemed to be related to the critical activity recorded in the right occipito-temporal region. The co-existence of visual hallucinations and the video-EEG correlation support this possibility. This phenomenon is probably due to epileptic activation of the cortical center of saccadic movements, with a rapid phase of nystagmus, contralateral to the focus, and a slow ipsilateral phase in association with a defect in the gaze-fixing system ("leaky neural integrator") [published with videosequences].