Obstructive sleep apnea (OSA) has been related to elevation of inflammatory cytokines and development of insulin resistance in morbidly obese (MO) subjects. However, it is still unclear whether the systemic concentration of anti-inflammatory mediators is also affected in MO subjects directly related to the severity of OSA and level of insulin resistance. Normal weight and MO subjects were subjected to overnight polysomnography in order to establish the severity of OSA, according to the apnea-hypopnea index (AHI). Blood samples were obtained for estimation of total cholesterol and triglycerides, insulin, glucose, insulin resistance, tumor necrosis factor alpha (TNF-α), interleukin 12 (IL12), and interleukin 10 (IL-10). Serum levels of IL-10 were significantly lower in MO subjects with OSA than in MO and control individuals without OSA. Besides being inversely associated with serum TNF-α and IL-12, decreased IL-10 levels were significantly related to increased AHI, hyperinsulinemia, and insulin resistance. Serum IL-10 is significantly reduced in morbidly obese subjects with severe OSA while also showing a clear relationship with a state of hyperinsulinemia and insulin resistance probably regardless of obesity in the present sample. It may be of potential clinical interest to identify the stimulatory mechanisms of IL-10 in obese individuals with OSA.

In the search of the sleep substance, many studies have been addressed for different hormones, responsible for sleep-wake cycle regulation. In this article we mentioned the participation of steroid hormones, besides its role regulating sexual behavior, they influence importantly in the sleep process. One of the clearest relationships are that estrogen and progesterone have, that causing changes in sleep patterns associated with the hormonal cycles of women throughout life, from puberty to menopause and specific periods such as pregnancy and the menstrual cycle, including being responsible for some sleep disorders such as hypersomnia and insomnia. Another studied hormone is cortisol, a hormone released in stressful situations, when an individual must react to an extraordinary demand that threatens their survival, but also known as the hormone of awakening because the release peak occurs in the morning, although this may be altered in some sleep disorders like insomnia and mood disorders. Furthermore neurosteroids such as pregnanolone, allopregnanolone and pregnenolone are involved in the generation of slow wave sleep, the effect has been demonstrated in experimental animal studies. Thus we see that the sleep and the endocrine system saved a bidirectional relationship in which depends on each other to regulate different physiological processes including sleep.

No abstract

The coronavirus disease (COVID-19) that broke out in China in December 2019 rapidly became a worldwide pandemic. In Mexico, the conditions requiring the declaration of a sanitary emergency were reached by the last week of March 2020, and health authorities’ limited mobility and imposed social isolation were the main strategies to keep the virus from spreading. Thus, daily living conditions changed drastically in a few days, generating a stressful situation characterized by an almost complete lack of mobility, social isolation, and forced full-time interactions with family members. Soon, complaints of sleep disturbances, anxiety, and symptoms of depression were reported. The present study reports the results of an online survey performed during the first two months of isolation. Questionnaires exploring sleep disturbances, anxiety, and depression were sent to people who responded to an open invitation. A total of 1230 participants filled out the sleep questionnaire, 812 responded to the anxiety questionnaire, and 814 responded to the depression questionnaire. Both men and women reported poor sleep quality, but women showed a higher proportion (79%) than men (60%); young women were more likely to be affected by social isolation. Concerning anxiety and depression, both sexes reported high similar symptoms. These data suggest that stressful conditions related to social isolation and the economic uncertainty caused by the pandemic may induce mental health disturbances, which may become worse with sleep restriction.

Depression in children is often an elusive disorder and its diagnostic tools are a matter of controversy. Several scales have been developed in an attempt to specifically detect some of the major aspects of depression, i.e. anhedonia, sadness, hopelessness. On the other hand, in adults depression frequently induces changes in sleep patterns, particularly a shortening in REM sleep latency. The alteration of sleep patterns in depressed children has been a matter of controversy. It is possible that a diagnostic deficiency might be the source of the contradictory reports. In the present study, The Child Depression Inventory, a rating scale specifically developed for child depression was applied to 396 school children (8-12 years of age). Nearly 15% of the children (N = 45) obtained scores higher than the established limit in this test for normal healthy subjects. A sample of children found within the highest (N = 25) and within the lowest (N = 25) scores in the scale were selected. After a clinical evaluation, only those who meet the inclusion criteria (N = 21 for depressed and N = 7 for healthy controls) were electroencephalographically recorded. Children with depressive symptoms showed a significant shortening in REM sleep latency (mean = 108 min) when compared to non-depressed (mean = 150 min). In addition, significant increases were observed in sleep latency, REM sleep duration and the number of awakenings. Furthermore, results showed an unexpected high frequency of EEG abnormalities in children with depressive symptoms (75%) characterized by sharp waves and polyspikes in the frontal region. The present results support the notion that depression, in children, is accompanied by changes in sleep patterns, mainly concerning REM sleep.

The Epworth Sleepiness Scale (ESS) has been reputed as a quick, valid, and reliable method to assess Daytime sleepiness (DS). Since its publication, it has been translated into a number of languages. Our aim was to determine validity and reliability indicators of an Spanish language version ESS for Mexican population. Considering that in developing countries the majority of persons use public transportation, validity and reliability indicators were also assessed utilizing the ESS without item 8. ESS was applied to a Group of college students (GCS), a selected group of Healthy subjects (HS), and a Group of patients with Sleep disorders (GPSD). We made an ESS comparison among the 3 groups, calculated the correlation between the ESS and the Multiple Sleep Latency Test (MSLT) and determined construct validity and internal consistency. GCS and GHS had lower ESS scores than GPSD. Regarding convergence validity, we obtained a negative correlation between the ESS and the MSLT; we also found a rise in the ESS score associated with an increase in the Apnea-hypopnea index (AHI). With respect to construct validity (employing main component analysis and varimax rotation), we found that one factor explains 52.01% of variance. We determined that the ESS internal consistency was 0.85. When item eight was suppressed, validity and reliability remained acceptable. The present ESS Spanish-language exhibited suitable levels of validity and reliability. Use of the ESS, suppressing item eight, allows assessment of DS more accurately in individuals who do not travel by automobile on a regular basis.

No abstract

Sleep clearly influences learning and memory since sleep deprivation and stress impairs both cognitive processes. Working memory is an essential cognitive process and refers to a short-term holding of incoming information required to update the long-term mnemonic storage and to manipulate new elements in order to solve problems and make decisions. Nevertheless, the influence of sleep deprivation on working memory has scarcely been studied. In this study we evaluated working memory using the N-back test after increasing periods of wakefulness. Healthy young males were kept awake for 36 hours and the two N-back tasks with low (1-Back) and high (3-Back) levels of complexity were applied every 6 hours. Additionally, salivary cortisol was determined along the study. Unlike the control non-deprived participants, the sleep deprived volunteers showed a significant decrease in their efficiency to solve the 1-Back task after 24 hours of sleep deprivation. However, no differences were observed after 30 and 36 hours of sleep deprivation. Concerning the 3-Back task no differences were observed after sleep deprivation. Regarding reaction time, the deprived group manifested slower responses for the 1-Back task and for the 3-Back task after 30 hours and 36 hours of sleep deprivation, respectively. Cortisol levels presented the normal daily oscillation and no differences were observed between groups. This data suggests that sleep deprivation affects basal states of attention instead of working memory while performing simple tasks. The impact of sleep deprivation on the cognitive performance depends on the moment of day when the task is applied and the complexity of the tests used to assess these mnemonic skills.