Sleep duration as an independent factor associated with vitamin D levels in the EPISONO cohort.

STUDY OBJECTIVES: Obstructive sleep apnea and short sleep duration have been separately associated with inadequate serum 25-hydroxyvitamin D [25(OH)D] levels. However, whether these 2 factors may concurrently influence 25(OH)D in the general population is unknown. We hypothesized that both obstructive sleep apnea and short sleep duration would be independently associated with lower concentrations of 25(OH)D in a sex-dependent manner. METHODS: In this cross-sectional study, 712 individuals, part of the prospective EPISONO cohort (Brazil), underwent polysomnography, answered sleep questionnaires, and had their blood collected for serum 25(OH)D quantification. RESULTS: Individuals with a sleep duration of < 6 hours had 2-fold increased odds of 25(OH)D < 20 ng/mL compared with those who reported 6 or more hours of sleep, even after adjusting for confounding factors. Subset sex analysis revealed that men with a sleep duration of < 6 hours had 4-fold increased odds of 25(OH)D < 20 ng/mL. In women, short sleep duration was not associated with lower 25(OH)D levels. The presence of obstructive sleep apnea (as classified according to the individual's apnea-hypopnea index) was not independently related to 25(OH)D concentrations in men or women. Sleep parameters, including sleep latency and sleep efficiency, had no association with 25(OH)D < 20 ng/mL. CONCLUSIONS: Short sleep, but not apnea-hypopnea index, was an independent factor associated with low 25(OH)D serum levels in men, but not in women. Apnea-hypopnea index scores were not associated with 25(OH)D levels in either sex. These results raise the possibility of investigating sex-specific characteristics, such as gonadal hormone regulation, and re-evaluating obstructive events by classifying them in mild, moderate, and severe obstructive sleep apnea. CITATION: de Oliveira DL, Dokkedal-Silva V, Fernandes GL, Kim LJ, Tufik S, Andersen ML. Sleep duration as an independent factor associated with vitamin D levels in the EPISONO cohort. J Clin Sleep Med. 2021;17(12):2439-2449.

The Role of Animal Models in Developing Pharmacotherapy for Obstructive Sleep Apnea.

Obstructive sleep apnea (OSA) is a highly prevalent disease characterized by recurrent closure of the upper airway during sleep. It has a complex pathophysiology involving four main phenotypes. An abnormal upper airway anatomy is the key factor that predisposes to sleep-related collapse of the pharynx, but it may not be sufficient for OSA development. Non-anatomical traits, including (1) a compromised neuromuscular response of the upper airway to obstruction, (2) an unstable respiratory control (high loop gain), and (3) a low arousal threshold, predict the development of OSA in association with anatomical abnormalities. Current therapies for OSA, such as continuous positive airway pressure (CPAP) and oral appliances, have poor adherence or variable efficacy among patients. The search for novel therapeutic approaches for OSA, including pharmacological agents, has been pursued over the past years. New insights into OSA pharmacotherapy have been provided by preclinical studies, which highlight the importance of appropriate use of animal models of OSA, their applicability, and limitations. In the present review, we discuss potential pharmacological targets for OSA discovered using animal models.

Narcolepsy, Precocious Puberty and Obesity in the Pediatric Population: a Literature Review.

Narcolepsy is a sleep disorder characterized by excessive daytime sleepiness, cataplexy, sleep paralysis and hypnagogic and hypnopompic hallucinations. The onset of the symptoms usually occurs in childhood, and previous studies have reported an association between narcolepsy and other endocrine diseases in the pediatric population, such as obesity and precocious puberty. The incidence of overweight or obesity ranges from 25% to 74% in patients with narcolepsy type I, while precocious puberty is present in 17% of children with narcolepsy with cataplexy. However, the mechanisms involved in the association of narcolepsy with obesity and precocious puberty have not been fully elucidated yet. In this review, we aimed to discuss narcolepsy in pediatric populations, highlighting the diagnostic difficulties and the complexity of the possible mechanisms that can relate narcolepsy to precocious puberty and obesity. We also emphasized the fact that endocrine diseases must be taken into consideration in children diagnosed with narcolepsy.

Sleep pattern and spectral analysis of caregiver-mothers of sons with Duchenne muscular dystrophy, and an examination of differences between carriers and non-carriers.

OBJECTIVES: Sleep is essential for physical and mental well-being. However, poor sleep is a common complaint among caregivers. The aim of the present study was to determine sleep patterns of caregiver-mothers (CM group) of sons with Duchenne muscular dystrophy (DMD) and also to examine the differences between non-carriers and carriers of the gene related to DMD within the CM group. METHODS: Observational case-control study. PARTICIPANTS: The CM and control (CTRL) groups were matched for age, body mass index and social class. Polysomnography was conducted in a sleep laboratory for one night. The discrete fast Fourier transformation method was used to calculate the electroencephalogram (EEG) power spectrum for the entire night and sleep stages. RESULTS: The CM group presented higher sleep latency and N3 sleep stage compared with the CTRL. When carrier and non-carrier CM subgroups were analyzed, increased sleep latency and time awake, as well as reduced sleep efficiency and N2, were observed in the carrier group. Regarding respiratory parameters, carriers demonstrated higher hypopnea index values compared with non-carriers. Spectral analysis showed that carriers compared with non-carrier DMD caregiver-mothers presented lower spectral power in fast waves, mainly beta, during REM sleep in some EEG derivations. CONCLUSIONS: There was an impairment of sleep pattern in the CM group compared with CTRL mothers; this was possibly associated with difficulty in initiating sleep. Being a DMD gene carrying caregiver further compromised some aspects of sleep microstructure during REM sleep. The data demonstrated the importance of sleep evaluation in caregiver-mothers, and the relationship between sleep and being a carrier of the gene associated with DMD, which was demonstrated as possibly impacting sleep quality.

Revisão sistemática sobre a epidemiologia das doenças cardiovasculares e respiratórias e suas associações com a poluição do ar em Vitória/ES / Epidemiology of cardiovascular and respiratory diseases and its associations with air pollution in Vitória, Brazil: a systematic review

Introdução: A poluição do ar é um importante fator ambiental relacionado a doenças crônicas não transmissíveis, como doenças cardiovasculares e respiratórias. Essa relação torna-se importante em cidades com alta atividade industrial, como Vitória/ES. Esta pesquisa utilizou três revisões sistemáticas (RSs) distintas para avaliar a epidemiologia das doenças cardiovasculares (RS1), a epidemiologia das doenças respiratórias (RS2) e a associação entre poluição do ar e doenças cardiorrespiratórias (RS3) na cidade de Vitória. Métodos: A busca bibliográfica considerou três bases de dados (PubMed, Scopus e LILACS). Foi estabelecida uma quantidade mínima de três estudos para a condução de metanálises. A heterogeneidade de cada análise foi calculada pelo índice I2. Resultados: A busca bibliográfica resultou em 1.205 registros, dos quais 27 foram incluídos ­ 17 na RS1, cinco na RS2 e cinco na RS3. Apenas dois desfechos puderam ser avaliados por meio de metanálises: prevalência de hipertensão e prevalência de asma em crianças. Estima-se uma prevalência de 34% (IC95%: 24-45) de hipertensão e de 12% (IC95%: 1-32) de asma em crianças. Os poluentes mais avaliados foram MP10 e SO2, para os quais não se pôde realizar metanálises. Todas as análises apresentaram baixo número de registros incluídos e alta heterogeneidade. Conclusão: Há poucos dados disponíveis sobre a associação de doenças cardiorrespiratórias e poluição ambiental em Vitória. A heterogeneidade, a diversidade de desfechos e a baixa quantidade de estudos impediram a condução de análises mais profundas e limitaram o poder de síntese e conclusão dessas revisões, impossibilitando uma avaliação adequada dos objetivos propostos. São necessários mais estudos epidemiológicos com amostras de grande porte e representativas para que se tenha resultados conclusivos sobre a relação entre poluição ambiental e doenças cardiorrespiratórias em Vitória (AU)

Introduction: Air pollution is an important environmental factor related to chronic non-transmittable diseases, including cardiovascular and respiratory diseases. This relationship is especially relevant in cities with high industrial activity, such as Vitória, Brazil. This research used three systematic reviews (SRs) to evaluate the epidemiology of cardiovascular diseases (SR1), the epidemiology of respiratory diseases (RS2), and the association between air pollution and cardiorespiratory diseases (RS3) in Vitória, Brazil. Methods: A bibliographic search was conducted in three independent databases (PubMed, Scopus and LILACS). A minimum amount of three studies was established to perform meta-analyses. Heterogeneity was calculated using the I2 index. Results: The bibliographic search retrieved 1205 references, of which 27 were included ­ 17 in SR1, five in SR2, and five in SR3. Only two outcomes could be evaluated through meta-analysis: prevalence of hypertension and prevalence of asthma in children. The most frequently evaluated pollutants were PM10 and SO2. The estimated prevalence of hypertension was 34% (CI95%: 24-45) and of asthma in children was 12% (CI95%: 1-32). All analyses had a limited number of included references and showed high heterogeneity. Conclusions: There are limited data available regarding the association of cardiorespiratory diseases and air pollution in Vitória, Brazil. The heterogeneity, the diversity of outcomes, and the limited number of studies hampered the performance of a more detailed analysis and limited the conclusions of these reviews, preventing a proper appraisal of the proposed aims. Further epidemiological studies with bigger and more representative sample sizes are needed to generate conclusive data about the relationship between air pollution and cardiorespiratory diseases in Vitória, Brazil (AU)

Sleep restriction reduces the survival time and aggravates the neurological dysfunction and memory impairments in an animal model of cerebral hypoperfusion.

Cerebral blood flow is associated with the cerebrovascular prognosis. Sleep restriction (SR) may be a limiting factor of the prognosis after a cerebrovascular event, impairing the neurological recovery. We aimed to investigate the effects of SR on mortality rate and on behavioral and histological parameters of animals submitted to permanent cerebral hypoperfusion. Sixty male Wistar rats were distributed in 4 groups, according to the protocol of common carotid artery occlusion (CCAO) and SR: nSR+nCCAO, SR+nCCAO, nSR+CCAO, and SR+CCAO. The groups SR+nCCAO and SR+CCAO were submitted to SR during 10 days. The cerebral hypoperfusion was induced by the permanent CCAO. Neurological function and memory were assessed over 14 days of cerebral hypoperfusion. Analysis of neuropathological alterations were performed in the CA1 region of hippocampus. The mortality rate was 40% in the nSR+CCAO and SR+CCAO groups. SR significantly reduced the survival time of animals submitted to CCAO. After 7 and 14 days of cerebral hypoperfusion, 11% and 33% of the nSR+CCAO and SR+CCAO animals showed severe neurological dysfunction, respectively. A significant association between a high frequency of memory impairments with the group SR+CCAO was observed. The neuropathological alterations in CA1 region of hippocampus were similar among the groups. SR potentiates the negative effects of cerebral hypoperfusion conditions, suggesting that SR could be a factor associated with a worse prognosis after a cerebrovascular event.

Frequencies and Associations of Narcolepsy-Related Symptoms: A Cross-Sectional Study.

OBJECTIVES: Narcolepsy is a disabling disease with a delayed diagnosis. At least 3 years before the disorder identification, several comorbidities can be observed in patients with narcolepsy. The early recognition of narcolepsy symptoms may improve long-term prognosis of the patients. Thus, we aimed to investigate the prevalence of the symptoms associated with narcolepsy and its social and psychological association in a sample of Sao Paulo city inhabitants. METHODS: We performed a cross-sectional evaluation with 1,008 individuals from the Sao Paulo Epidemiologic Sleep Study (EPISONO). Excessive daytime sleepiness (EDS) was assessed by the Epworth Sleepiness Scale. Volunteers were also asked about the occurrence of cataplectic-like, hypnagogic or hypnopompic hallucinations, and sleep paralysis symptoms. The participants underwent a full-night polysomnography and completed questionnaires about psychological, demographic, and quality of life parameters. RESULTS: We observed a prevalence of 39.2% of EDS, 15.0% of cataplectic-like symptom, 9.2% of hypnagogic or hypnopompic hallucinations, and 14.9% of sleep paralysis in Sao Paulo city inhabitants. A frequency of 6.9% was observed when EDS and cataplectic-like symptoms were grouped. The other associations were EDS + hallucinations (4.7%) and EDS + sleep paralysis (7.5%). Symptomatic participants were predominantly women and younger compared with patients without any narcolepsy symptom (n = 451). Narcolepsy symptomatology was also associated with a poor quality of life and symptoms of depression, anxiety, and fatigue. CONCLUSIONS: Narcolepsy-related symptoms are associated with poor quality of life and worse psychological parameters.

Treatment of obstructive sleep apnea syndrome associated with stroke.

The association between sleep-disordered breathing and stroke has been a subject of increased interest and research. Obstructive sleep apnea (OSA) is an important risk factor for stroke incidence and mortality. Moreover, OSA is a common clinical outcome after stroke, directly influencing the patient's recovery. The treatment of choice for OSA is positive airway pressure (PAP) support and the PAP appliance is considered the most recommended clinical management for the treatment of patients with cardiovascular complications. However, the implementation of PAP in stroke patients remains a challenge, considering the increased frequency of motor and language impairments associated with the cerebrovascular event. In the present study, we reviewed the main findings describing the association between stroke and OSA treatment with continuous positive airway pressure. We also discussed the types of OSA treatment, the different options and indications of PAP treatment, PAP adherence and the clinical outcomes after treatment.

Is the chronotype associated with obstructive sleep apnea?

PURPOSE: Chronotype and obstructive sleep apnea (OSA) appear to have a similar lifelong evolution, which could indicate a possible effect of morningness or eveningness in the apnea-hypopnea index (AHI). The present study aimed to examine the prevalence of chronotypes in a representative sample of São Paulo city residents and to investigate the effect of chronotypes on the severity of OSA. METHODS: We performed a cross-sectional analysis using the São Paulo Epidemiologic Sleep Study (EPISONO). All participants underwent a full-night polysomnography and completed the Morningness-eveningness, Epworth Sleepiness Scale, and UNIFESP Sleep questionnaires. Chronotypes were classified as morning-type, evening-type, and intermediate. RESULTS: Morning-type individuals represented 52.1% of the sample, followed by intermediate (39.5%), and evening-type (8.4%) individuals. After stratifying the sample by body mass index (BMI) (>26.8 kg/m(2)) and age (>42 years), we observed increased AHI values in morning- and evening-type individuals. CONCLUSION: We demonstrated, for the first time, an age- and BMI-related effect of morning- and evening-types in OSA severity, suggesting that the intermediate chronotype might play a role as a protective factor in older and overweight patients.

Hypomyelination, memory impairment, and blood-brain barrier permeability in a model of sleep apnea.

We investigated the effect of intermittent hypoxia, mimicking sleep apnea, on axonal integrity, blood-brain barrier permeability, and cognitive function of mice. Forty-seven C57BL mice were exposed to intermittent or sham hypoxia, alternating 30s of progressive hypoxia and 30s of reoxigenation, during 8h/day. The axonal integrity in cerebellum was evaluated by transmission electron microscopy. Short- and long-term memories were assessed by novel object recognition test. The levels of endothelin-1 were measured by ELISA. Blood-brain barrier permeability was quantified by Evans Blue dye. After 14 days, animals exposed to intermittent hypoxia showed hypomyelination in cerebellum white matter and higher serum levels of endothelin-1. The short and long-term memories in novel object recognition test was impaired in the group exposed to intermittent hypoxia as compared to controls. Blood-brain barrier permeability was similar between the groups. These results indicated that hypomyelination and impairment of short- and long-term working memories occurred in C57BL mice after 14 days of intermittent hypoxia mimicking sleep apnea.