Cronotipo, jetlag social e duração do sono : fatores associados à síndrome metabólica?

Abstract

Introduction: The increased frequency of metabolic syndrome (MS) is associated with different standards and lifestyles, including alteration of the sleep-wake cycle resulting from working in alternating and night shifts, thus is seen at an even greater proportion when compared to day workers. Objective: To analyze the association of chronotype, social jetlag and sleep duration with MS among night workers who are overweight, as well as to identify its prevalence and compare with sociodemographic, work, health and lifestyle variables. Methods: This is a crossover randomized, double-blind, controlled clinical trial, for which in the present study only the baseline data were analyzed. The study sample consisted of 36 nursing professionals from a hospital unit located in the city of São Paulo. The research participants answered a questionnaire on sociodemographic, work, health and lifestyle variables and were assessed anthropometrically, as well as blood pressure. Fasting blood was collected in order to obtain plasma concentrations of blood glucose, serum triglycerides and HDL-cholesterol. To assess the chronotype, social jetlag and sleep duration, the Munich Chronotype Questionnaire for Shift-Workers (MCTQshift) was used. To assess the association between sleep duration, chronotype and social jetlag with MS, a difference in means test (General Linear Models ¿ GLM) was performed. Statistical analyses were performed using STATISTICA version 7.0 and Stata version 12.0 (Stata Corp., Texas, USA) software. Results: The prevalence of MS was 27.8%. No differences were found in the proportions for sociodemographic, work, health and lifestyle variables according to the presence or absence of MS. Likewise, there was no association between sleep duration, chronotype, social jetlag and MS. Conclusion: Although the prevalence of MS was high in the researched group, sleep duration, chronotype and social jetlag are not associated with MS among overweight nighttime nursing workers. The sociodemographic, work, health and lifestyle variables were also unrelated to the presence or absence of MS.