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In this chapter we describe the history, research, education, and practice of sleep medicine in Argentina, pointing out the importance of the role of public policies in the development of sleep medicine grounds. With the drawbacks of a developing or “emerging” country, sleep medicine in Argentina has been growing up in the past decades. This fact allows us to be optimistic despite the unfavorable scenarios that our country usually goes through. Sleep medicine in Argentina is still rather young in the field of medicine and needs much more effort to consolidate as a specialty.

Study Objectives Although sympathetic hyperactivity with preserved parasympathetic activity has been extensively recognized in fatal familial insomnia (FFI), the symptoms of parasympathetic nervous system failure observed in some patients are difficult to explain. Using heart rate variability (HRV), this study aimed to discover evidence of parasympathetic dysfunction in patients with FFI and the difference of parasympathetic activity between patients with FFI and Creutzfeldt–Jakob disease (CJD). Methods This study enrolled nine patients with FFI, eight patients with CJD and 18 healthy controls (HCs) from May 2013 to August 2020. All participants underwent a nocturnal video-polysomnography with lead II electrocardiography, and the data were analyzed using linear and nonlinear indices of HRV during both wake and sleep states. Results Compared to the HC and CJD groups, the FFI group had a continuously higher heart rate with a lower amplitude of oscillations. The low frequency (LF)/high frequency (HF) ratio and ratio of SD1 to SD2 and correlation dimension D2 (CD2) were significantly different in the FFI group compared to the HC group. The root mean square of successive differences (RMSSD), HF and SD1 in the FFI group were significantly lower than in the HC group. RMSSD, SD1, and CD2 in the FFI group were all significantly lower than in the CJD group. Conclusions Cardiovascular dysautonomia in FFI may be partly attributable to parasympathetic abnormalities, not just sympathetic activation. HRV may be helpful as a noninvasive, quantitative, and effective autonomic function test for FFI diagnosis.

Background The understanding of fatal familial insomnia (FFI), a rare neurodegenerative autosomal dominant prion disease, has improved in recent years as more cases were reported. This work aimed to propose new diagnostic criteria for FFI with optimal sensitivity, specificity, and likelihood ratio. Methods An international group of experts was established and 128 genetically confirmed FFI cases and 281 non-FFI prion disease controls are enrolled in the validation process. The new criteria were proposed based on the following steps with two-round expert consultation: (1) Validation of the 2018 FFI criteria. (2) Diagnostic item selection according to statistical analysis and expert consensus. (3) Validation of the new criteria. Results The 2018 criteria for possible FFI had a sensitivity of 90.6%, a specificity of 83.3%, with a positive likelihood ratio (PLR) of 5.43, and a negative likelihood ratio (NLR) of 0.11; and the probable FFI criteria had a sensitivity of 83.6%, specificity of 92.9%, with a PLR of 11.77, and a NLR of 0.18. The new criteria included more specific and/or common clinical features, two exclusion items, and summarized a precise and flexible diagnostic hierarchy. The new criteria for possible FFI had therefore reached a better sensitivity and specificity (92.2% and 96.1%, respectively), a PLR of 23.64 and a NLR of 0.08, whereas the probable FFI criteria showed a sensitivity of 90.6%, a specificity of 98.2%, with a PLR of 50.33 and a NLR of 0.095. Conclusions We propose new clinical diagnostic criteria for FFI, for a better refining of the clinical hallmarks of the disease that ultimately would help an early recognition of FFI and a better differentiation from other prion diseases.

The mandatory social isolation (MSI) due to the pandemic caused by COVID-19 in the world produced many changes in sleep and different areas of mental health. Objectives: To evaluate the early effects of MSI on sleep, anxiety, and depression in Argentina.An anonymous observational cross-sectional web-based study was distributed throughout the country and was completed by 2,594 respondents to analyze demographic information, quality of sleep, REM sleep-related events, depressive, and anxiety symptoms.The study revealed that 53, 21, 22, 23, and 16% of people surveyed were poor sleepers, had dream-related behaviors, nightmares, depression, and anxiety symptoms, respectively. Multivariate logistic regression showed a positive correlation between anxiety, being a poor sleeper, and having nightmares.We identified the early effects of MSI on sleep quality, dreaming activity, anxiety, and depression in Argentina during the COVID-19 outbreak. Our findings can be used to formulate sleep and psychological interventions to improve mental health during the pandemic and post-pandemic times.

Objectives At the end of 2019 the SARS-CoV-2 outbreak spread around the globe with a late arrival to South America. The objective of this study was to evaluate the impact of the long period of mandatory social isolation that took place in Argentina on the general psychological well-being of healthcare workers due to the COVID-19 pandemic. Methods A survey was conducted during June 2020, in healthcare workers. Pittsburgh Sleep Quality Index, Insomnia Severity Index, Sleepiness-Wakefulness Inability and Fatigue Test, and Goldberg depression and anxiety scale, were used to analyze the effects of the SARS-Cov 2 outbreak after three months of mandatory social isolation. Analyses were performed by logistic regression and a clustering algorithm in order to classify subjects in the function of their outcome's severity. Results From 1059 surveys, the majority reported symptoms of depression (81.0%), anxiety (76.5%), poor sleep quality (84.7%), and insomnia (73.7%) with 68.9% suffering from nightmares. Logistic regression showed that being in contact with COVID-19 patients, age, gender and the consumption of sleep medication during the mandatory social isolation were relevant predictors for insomnia, anxiety, and depression. Clustering analysis classified healthcare workers in three groups with healthy/mild, moderate, and severe outcomes. The most vulnerable group was composed mainly of younger people, female, non-medical staff, or physicians in training. Conclusion An extremely high proportion of Argentinian healthcare workers suffered from sleep problems, anxiety, and depression symptoms. The clustering algorithm successfully separates vulnerable from non-vulnerable populations suggesting the need to carry out future studies involving resilience and vulnerability factors., Highlights • COVID-19 social isolation is related to insomnia, anxiety, and depression symptoms. • Nightmares were correlated with high levels of anxiety during COVID-19 outbreak. • Younger people, women, and non-medical health workers were the most affected population. • K-means algorithm successfully separates vulnerable from non-vulnerable populations.

Kleine-Levin syndrome is an uncommon disorder with recurrent episodes of hypersomnia, and behavioral abnormalities such as binge-eating and hypersexuality. Our aims were to report cases of the Kleine-Levin syndrome diagnosed in Buenos Aires, Argentina and to characterize the clinical presentation of these patients. We evaluated patients with Kleine-Levin syndrome according to the International Classification of Sleep Disorders. Psychiatric, physical and neurological symptoms were present. Some patients were investigated with brain Magnetic Resonance Imaging, Single Photon Emission Computed Tomography, electroencephalogram and some with polysomnography. Seven patients (2 female, 5 male), ages from 8 to 47 years (median 20.7 years) were included in the study. The duration of symptoms was 1.5-20 days with a mean of 8. The range of interval between episodes: 2.5-24 months, median=13. All seven patients had a history of hypersomnia (one of them post head injury); 5 reported hyperphagia and 2 reduced appetite. Brain MRI was performed in 6 patients: 1 showed non-specific abnormalities and another presented diencephalic hematoma; the rest were normal. Our paper is the first one in Buenos Aires reporting Kleine-Levin syndrome of different ethiologies. The prevalence is difficult to estimate in our country.

Under the hypothesis that the uncontrolled neuronal synchronization propagates recruiting more and more neurons, the aim is to detect its onset as early as possible by signal analysis. This synchronization is not noticeable just by looking at the EEG, so mathematical tools are needed for its identification. Objective. The aim of this study is to compare the results of spectral entropies calculated in different frequency bands of the EEG signals to decide which band may be a better tool to predict an epileptic seizure. Materials and Methods. Invasive ictal records were used. We measured the Fourier spectrum entropy of the electroencephalographic signals 4 to 32 minutes before the attack in low, medium and high frequencies. Results. The high-frequency band shows a markedly rate of increase of the entropy, with positive slopes and low correlation coefficient. The entropy rate of growth in the low-frequency band is practically zero, with a correlation around 0.2 and mostly positive slopes. The mid-frequency band showed both positive and negative slopes with low correlation. Conclusions. The entropy in the high frequencies could be predictor, because it shows changes in the previous moments of the attack. Its main problem is the variability, which makes it difficult to set the threshold that ensures an adequate prediction. Fil: Blanco, Susana Alicia Ana. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Belgrano. Facultad de Ingenieria; Argentina Fil: Garay, Arturo. Centro de Educación Médica e Investigaciones Clínicas; Argentina Fil: Coulombie, Diego. Universidad Nacional de la Matanza. Instituto de Investigación y Desarrollo; Argentina

The effects of increasing calcium concentration and isoproterenol on myocardial relaxation were compared in cat and rat papillary muscles and toad ventricular strips. Isoproterenol effects were studied at equivalent positions of the calcium contractility response curve in the three species: at the plateau and at 25% and 50% of maximum. Calcium concentration was increased from the 25% point to the plateau of the calcium contractility curve for each species. Contractility was characterized by maximal velocity of tension development (+Ṫ). To study the relaxation phase, the following parameters were measured: maximal velocity of relaxation, (−Ṫ), the relationship between +Ṫ and −Ṫ (+Ṫ/−Ṫ), time to peak tension (TTP), time to half relaxation (t 1/2), relaxation time (Rt), total twitch duration (Tt) and the time constant of isometric tension decline from the time of −Ṫ (Tau). In rat muscles, t 1/2, Rt and Tt at all calcium levels, and Tau and +Ṫ/−Ṫ at the 50% and 100% of the calcium contractility curve, behaved as ‘lusitropic’: they significantly decreased with isoproterenol and not with calcium. Similar results were obtained in cat muscles except that at the 50% point of the calcium contractility curve, +Ṫ/−Ṫ was not significantly decreased. The behaviour of toad ventricle was different from that of mammalian heart: +Ṫ/−Ṫ and Tau appeared as lusitropic at all levels of the calcium curve, whereas only at the plateau some of the ‘time’ parameters were able to discriminate the isoproterenol lusitropic effect. These differences may reflect the strong dependence in amphibian heart of the time course of the action potential duration, not observed in mammalian ventricle.