Um estudo psicofisiológico da síndrome da apnéia obstrutiva do sono: avaliação do impacto sobre depressão, memória e sonolência diurna

Abstract

The acknowkedgement of the importance of sleep for human health and its systemized study made it possible to identify specific sleep diseases and among the diseases identified the Obstructive Sleep Apnea Syndrome (OSAS) stands out. This syndrome consists of arrests in breathing that occur during sleep due to the closing of upper airways. As breathing totally ceases or partially ceases, there is a decrease in the levels of oxigen in the bloof trigerring a central response of arousal or microarousal which in turn fragmentizes sleep, making sleep superficial and non recovering. Consequently, problems are brought on for the person during the period of awakeness. Recently, psychological correlates of OSAS have been studied, revealing evidences of the relation between this sydrome and depression, daytime sleepiness and memory loss. The goal of this study was to verify the correlation of OSAS with depression,daytime sleepiness and daily memory. The hypotheses were that a higher level of sleep would be associated with more seve dpressive states, significant losses of daily memory, as well as the increase in daytime sleepiness. The sample was made up of 30 patients from 29 to 59 years old and were treated at a private hospital in the city of Patos de Minas, Brasil. Nineteen were male and eleven female. In a routine medical diagnosis, patients were submitted to a polysomnography in which physiological measures ( i.e. number of sleep apneas/hypoapneas per hour) were taken during sleep. Patients who reached the sleepapnea/hypoapnea index (AHI) compatible with the syndromes characterization (AHI > 5 events/hour) were invited to participate in the study. Participants completed Beck Depression Inventary (BDI), Questionaire of Daily Forgets (QEC-Questionário dos Esquecimentos Diários) and Epworth Sleepiness Scale (Epworth).Spearman coeficients between AHI-BDI, AHI-QEC, AHI-Epworth were calculated. Kruskal-Wallis was also performed to verify the division of the groups according to the level of OSAS severity. The hypotheses of the study were not confirmed however, correlations between the following variables were found: AHIsleep eficiency, AHI- slow wave sleep, QEC-BDI. As for the Kruskal-Wallis test, statistically significant differences between groups were detected when AHI and percentage of slow wave sleep were evaluated. Although the present study show no linear correlation between OSAS and depression, daily memory and daytime sleepiness, analysis of the correlations as a whole suggests future lines of investigation such as the relation between depression and memory as well as memory with daytime sleepiness and REM sleep.