The Impact of Shift Work on Brazilian Train Drivers with Different Chronotypes: A Comparative Analysis through Objective and Subjective Criteria

Centro de Estudo Multidisciplinar em Sonolência e Acidentes (CEMSA), São Paulo, Brazil.
Medical Principles and Practice (Impact Factor: 0.96). 01/2013; 22(4). DOI: 10.1159/000345978
Source: PubMed

ABSTRACT Objective: The aim of this study was to compare sleep pattern, tiredness sensation and quality of life between different chronotypes in train drivers from a Brazilian transportation company. Subjects and Methods: Ninety-one train drivers, working a rotary work schedule including night shift, were divided into three groups according to their chronotype (morning types, intermediate or evening types) and were assessed for their sleep and quality of life, as characterized by a subjective questionnaire and the Psychomotor Vigilance Task (PVT), applied before and immediately after the night shift. The pattern of activity and rest was measured for 10 days by actigraphy, and the chronotype was determined through the Morningness-Eveningness Questionnaire. Results: Forty-one (45.1%) individuals were classified as morning type, 44 (48.4%) were classified as intermediate and 6 (6.6%) as evening type. The evening types had a tendency to remain awake for a longer period of time before the night shift (p = 0.05) and scored worse overall for quality of life compared to morning types (p = 0.11). There was no significant difference between the groups regarding variability in the PVT performance, even when covaried by the period of waking time before the test. There was no significant difference either in feelings of fatigue before and after starting the shift. Conclusion: Although the evening type number was small, evening type individuals scored worse relative to sleep and quality of life than morning type individuals.

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    ABSTRACT: Objective: The objective of this study was to analyze the effect of individual circadian preferences of drivers with fixed night work schedules on sleep patterns. Subjects and Methods: A total of 123 professional drivers, 32 indifferent preference drivers and 91 morning preference drivers of an intermunicipality and interstate bus transportation company were evaluated. All drivers underwent polysomnographic recordings after their shifts. Furthermore, they filled out a questionnaire that contained sociodemographic and health questions. The Horne and Östberg questionnaire was used to assess the subjects' morningness-eveningness preference. Results: The mean age was 42.54 ± 6.98 years and 82 (66.66%) of the drivers had worked for ≥15 years. A significant effect on rapid eye movement (REM) was observed in the morning preference drivers. They showed an increased sleep latency and an REM sleep percentage of 5% of the total REM time. This reveals a significant effect on sleep architecture associated with work time. Conclusion: The drivers reported that morning preference had a significant effect on their sleep pattern indicating less REM sleep and longer REM sleep latency in the morning preference group. Thus, it is important to evaluate interactions between individual aspects of health and other parameters, such as sleep quality and work organizational factors, to promote night shift workers' health and well-being. © 2013 S. Karger AG, Basel.
    Medical Principles and Practice 08/2013; 22(6). DOI:10.1159/000354104 · 0.96 Impact Factor
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    ABSTRACT: 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.
    Sleep And Breathing 10/2014; DOI:10.1007/s11325-014-1070-1 · 2.87 Impact Factor


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May 29, 2014