Imbalance between thyroid hormones and the dopaminergic system might be central to the pathophysiology of restless legs syndrome: a hypothesis

Data collected from medical literature indicate that dopaminergic agonists alleviate Restless Legs Syndrome symptoms while dopaminergic agonists antagonists aggravate them. Dopaminergic agonists is a physiological regulator of thyroid-stimulating hormone. Dopaminergic agonists infusion diminishes the levels of thyroid hormones, which have the ability to provoke restlessness, hyperkinetic states, tremors, and insomnia. Conditions associated with higher levels of thyroid hormones, such as pregnancy or hyperthyroidism, have a higher prevalence of Restless Legs Syndrome symptoms. Low iron levels can cause secondary Restless Legs Syndrome or aggravate symptoms of primary disease as well as diminish enzymatic activities that are involved in dopaminergic agonists production and the degradation of thyroid hormones. Moreover, as a result of low iron levels, dopaminergic agonists diminishes and thyroid hormones increase. Iron therapy improves Restless Legs Syndrome symptoms in iron deprived patients. Medical hypothesis. To discuss the theory that thyroid hormones, when not counterbalanced by dopaminergic agonists, may precipitate the signs and symptoms underpinning Restless Legs Syndrome. The main cause of Restless Legs Syndrome might be an imbalance between the dopaminergic agonists system and thyroid hormones

Sleep disorders frequency in post-polio syndrome patients caused by periodic limb movements

Post-polio syndrome (PPS) in individuals with polio longer than 15 years is characterized by weakness and/or muscle fatigue, deficit of deglutition and breath and periodic limb movements (PLM) during sleep. We undertook a review of 99 patients with PPS, and assessed the frequency of PLM through polysomnographic recordings at our sleep disorders unit. the total number of PLK total time of sleep (TTS), efficiency of sleep (EfS), awaking index (AI) and apnea-hypopnea index (AHI) were analyzed. Sixteen patients presented PLM in excess of 5 for the entire night. When comparing these with the group without PLM, a correlation was found (p=0.001). Significant difference was found for the correlation of the parameters: IAH, ID, TTS and EfS when compared the two groups. There is a close relationship between PPS and PLM.Universidade Federal de São Paulo, EPM, Inst Sono, São Paulo, BrazilUniversidade Federal de São Paulo, EPM, Inst Sono, São Paulo, BrazilWeb of Scienc

Treatment of sleep central apnea with non-invasive mechanical ventilation with 2 levels of positive pressure (bilevel) in a patient with myotonic dystrophy type 1

AbstractWe are reporting a case of a 29 year-old female with diagnosis of myotonic dystrophy type 1 (Steinert’s disease) with excessive daytime sleepiness, muscle fatigue, snoring, frequent arousals, non-restorative sleep, and witnessed apneas. Pulmonary function tests revealed a mild decrease of forced vital capacity. Nocturnal polysomnography showed an increase of apnea/hypopnea index (85.9 events/h), mainly of central type (236), minimal oxygen saturation of 72%, and end-tidal carbon dioxide values that varied from 45 to 53 mmHg.Bi-level positive airway pressure titration was initiated at an inspiratory pressure (IPAP) of 8 and an expiratory pressure (EPAP) of 4 cm H2O. IPAP was then gradually increased to eliminate respiratory events and improve oxygen saturation. An IPAP of 12cm H20 and an EPAP of 4cm H2O eliminated all respiratory events, and the oxygen saturation remained above 90%.Bi-level positive airway pressure treatment at spontaneous/timed mode showed an improvement in snoring, apneas, and Epworth sleepiness scale decreased from 20 to 10. This case illustrates the beneficial effects of Bi-level positive airway pressure support in central sleep apnea syndrome of a patient with myotonic dystrophy type 1

Cyclic alternating pattern in normal children aged 12 to 24 months Padrão alternante cíclico em crianças normais de 12 a 24 meses

OBJECTIVE: The aim of this study is to complement existing data on the expression and characteristics of cyclic alternating pattern (CAP) in children, specifically in the 12 to 24 month age bracket. METHOD: Descriptive study. Settings: a university pediatric sleep laboratory. Participants: Twelve normal and healthy subjects (6 girls and 6 boys, mean age 18.9±4.72 months; range 12-24 months underwent a standard polysomnography night recording in our pediatric sleep laboratory. Sleep stages and CAP were analyzed according to standard international rules. RESULTS: CAP rate found in children of 12 to 24 months of age was (25.78±10.18%) and it is characterized by a linear increase of 2% per month, from 12% at 12 months reaching 35% at 24 months. With coefficient of determination R² of 0.91. The duration of A phases was 6.93±1.06 seconds, and B phases was found to last 21.44±2.31 seconds. The number of CAP cycles was 173.25±73.85 with an average index per hour of 33.55±14.61. The number of CAP sequences reached 25.25±9.55 per recording. CAP rate for the different type of A phases are (21.83±9.68%), for A1, (2.43±2.30%) for A3 and (1.67±1.11%) for A2. CONCLUSION: Our study provides normative data on CAP in a group of young children (12 to 24 months). The most salient result of this study is the strong correlation of CAP rate of 2% per month in this age group.OBJETIVO: O objetivo deste estudo é complementar os dados normativos sobre a expressão e as características do padrão alternante cíclico (CAP) em crianças, especificamente na faixa etária de 12 para 24 meses. MÉTODO: Estudo descritivo. Participantes: Doze indivíduos normais e saudáveis (6 meninas e 6 meninos, entre 12-24 meses de idade (média de 18,9±4,72 meses), foram submetidos a uma noite de gravação de polissonografia em nosso laboratório de sono pediátrico. As fases do sono e CAP foram analisados de acordo com padrão e normas internacionais. RESULTADOS: A taxa máxima encontrada em crianças de 12 a 24 meses de idade foi de (25,78%±10,18) e é caracterizada por um aumento linear de 2% ao mês, a partir de 12% em 12 meses atingindo 35% em 24 meses de idade. A duração da fase A foi de 6,93±1,06 segundos, e nas fases B foi encontrado a média de 21,44±2,31 segundos. O número de ciclos CAP foi 173,25±73,85, com um índice médio por hora de 33,55±14,61. O número de sequências CAP chegou a 25,25±9,55 por registro.Os índices dos subtipos de fases A foram (21,83%±9,68), para a A1, (2,43%±2,30) para a A3 e (1,67%±1,11) para A2. CONCLUSÃO: Nosso estudo fornece dados normativos sobre CAP em um grupo de crianças (12 a 24 meses de idade). O resultado mais saliente deste estudo é a forte correlação entre taxa do CAP e idade, mostrando que a cada mês ocorreu o aumento de 2%

Acute glucocorticoid effects on the multicomponent model of working memory

Objective in comparison with basal physiological levels, acute, high levels of cortisol affect learning and memory. Despite reports of cortisol-induced episodic memory effects, no study has used a comprehensive battery of tests to evaluate glucocorticoid effects on the multicomponent model of working memory. Here, we report the results of a double-blind, placebo-controlled, between-subjects study.Methods Twenty healthy young men were randomly assigned to either acute cortisol (30 mg hydrocortisone) or placebo administration. Participants were subjected to an extensive cognitive test battery that evaluated all systems of the multicomponent model of working memory, including various executive domains (shifting, updating, inhibition, planning and access to long-term memory).Results Compared with placebo, hydrocortisone administration increased cortisol blood levels and impaired working memory in storage of multimodal information in the episodic buffer and maintenance/reverberation of information in the phonological loop. Hydrocortisone also decreased performance in planning and inhibition tasks, the latter having been explained by changes in storage of information in working memory.Conclusions Thus, hydrocortisone acutely impairs various components of working memory, including executive functioning. This effect must be considered when administering similar drugs, which are widely used for the treatment of many clinical disorders. Copyright (C) 2011 John Wiley & Sons, Ltd.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Associacao Fundo de Incentivo a Pesquisa (AFIP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Universidade Federal de São Paulo, Dept Psychobiol, Escola Paulista Med, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Psychobiol, Escola Paulista Med, São Paulo, BrazilFAPESP: 2005/00362-3Web of Scienc

Effect of Acute and Chronic Physical Exercise on Patients with Periodic Leg Movements

ESTEVES, A. M., M. T. DE MELLO, M. PRADELLA-HALLINAN, and S. TUFIK. Effect of Acute and Chronic Physical Exercise on Patients with Periodic Leg Movements. Med. Sci. Sports Exerc., Vol. 41, No. 1,. pp. 237-242, 2009. Purpose: Nonpharmacological interventions may lead to an improvement in sleep quality. The objective of our study was to evaluate the effects of acute intensive exercise and chronic exercise on sleep patterns in patients with periodic leg movements (PLM). Methods: The study involved acute and chronic exercise. The acute intensive exercise group consisted of 22 volunteers who underwent a maximum effort test and a polysomnography (PSG) on the same night. The chronic exercise group included. 11 patients who performed 72 physical training sessions undergoing three PSG studies on the night of sessions 1, 36, and 72. Blood samples were collected from both acute and chronic groups for beta-endorphin dosage. Results: Our results showed that both forms of physical exercise lowered PLM levels. The acute physical exercise increased sleep efficiency, rapid eye movement (REM) sleep, and reduced wake after sleep onset, whereas the chronic physical exercise increased sleep efficiency, REM sleep, and reduced sleep latency. We also found a significant negative correlation between beta-endorphin release after acute intensive exercise and PLM levels (r = -0.63). Conclusion: Physical exercise may improve sleep patterns and reduce PLM levels. The correlation between beta-endorphin release after acute intensive exercise and PLM levels might be associated with the impact physical exercise has on the opiodergic system. We suggest that physical exercise may be a useful nonpharmacological treatment for PLM.FAPESP[03/06297-3]FAPESP[CEPID 98/143033]Psychopharmacological Research Support Foundation (AFIP