Claudia Roberta de Castro Moreno

Short Sleep Is Associated with Obesity Among Truck Drivers

Recent studies suggest that short‐sleep duration is independently associated with obesity in the general population. The population of truck drivers is of particular interest, because they frequently work irregular shifts that in turn are associated with short‐sleep duration. In addition, truck drivers have a high prevalence of sedentary habits, poor diet, and obesity. The present study aimed at verifying the association between sleep patterns and factors associated with obesity in this population. The study sample consisted in 4,878 truck drivers who participated in a campaign promoted by a highway company in the State of São Paulo, Brazil. This campaign offered highway truck drivers a medical and laboratorial evaluation. The truck drivers completed a questionnaire concerning demographic data, sleep duration, consumption of medications, and medical problems, such as diabetes, cardiopathy, and hypertension; as well as the Berlin questionnaire, which is able to discriminate low and high risk for obstructive sleep apnea. Blood samples were collected to measure glucose and cholesterol levels. Also, body weight and height were registered to calculate the body mass index (BMI). The mean age (±SD) of the truck drivers studied was 40±10 years. Out of the truck drivers analyzed, 28.3% (n=1,379) had a BMI ≥30.0 Kg/m2 (obesity). Among the 4,878 drivers included in the study, 1,199 (24.6%) were on medications and 334 (6.8%) were diabetic. Drivers (26.9%) with the greater BMI had a short sleep length. The independent factors associated with obesity were sleep duration <8 h/day (OR=1.24), age >40 years (OR=1.20), glucose levels >200 (OR=2.02), cholesterol levels >240 (OR=1.57), snoring (OR=1.74), and hypertension (OR=2.14). Smoking was not associated with obesity (OR=0.69), and diabetes was considered a control variable. In conclusion, this study supports the hypothesis that short sleep duration as well as age >40 years are independently associated with obesity. This particular combination (short‐sleep duration and obesity) is independently associated with several healthcare problems, including high levels of cholesterol, glucose, snoring, and hypertension. However, due to the cross‐sectional nature of this study, no cause–effect relationship can be drawn from these results.

Sleep and sleepiness among working and non-working high school evening students.

The aim of this study was to evaluate patterns of sleepiness, comparing working and non‐working students. The study was conducted on high school students attending evening classes (19:00–22:30 h) at a public school in São Paulo, Brazil. The study group consisted of working (n=51) and non‐working (n=41) students, aged 14–21 yrs. The students answered a questionnaire about working and living conditions and reported health symptoms and diseases. For seven consecutive days, actigraphy measurements were recorded, and the students also filled in a sleep diary. Sleepiness ratings were given six times per day, including upon waking and at bedtime, using the Karolinska Sleepiness Scale. Statistical analyses included three‐way ANOVA and t‐test. The mean sleep duration during weekdays was shorter among workers (7.2 h) than non‐workers (8.8 h) (t=4.34; p<.01). The mean duration of night awakenings was longer among workers on Tuesdays and Wednesdays (28.2 min) and shorter on Mondays (24.2 min) (t=2.57; p=.03). Among workers, mean napping duration was longer on Mondays and Tuesdays (89.9 min) (t=2.27; p=.03) but shorter on Fridays and Sundays (31.4 min) (t=3.13; p=.03). Sleep efficiency was lower on Fridays among non‐workers. Working students were moderately sleepier than non‐workers during the week and also during class on specific days: Mondays (13:00–15:00 h), Wednesdays (19:00–22:00 h), and Fridays (22:00–00:59 h). The study found that daytime sleepiness of workers is moderately higher in the evening. This might be due to a work effect, reducing the available time for sleep and shortening the sleep duration. Sleepiness and shorter sleep duration can have a negative impact on the quality of life and school development of high school students.

The Nutritional Status and Eating Habits of Shift Workers: A Chronobiological Approach

The eating habits of workers may vary according to the season of the year and corresponding work schedule. A study aiming at verifying the changes in their diet in summer and winter, as well as the nutritional status of those who work fixed shifts, was conducted. The distribution during the 24 h in the quantity of calories and macronutrients ingested and the circadian rhythm of calories consumed were also analyzed. The study was conducted on 28 workers subject to three fixed work (morning, afternoon, and night) shifts at a transport company in the city of São Paulo, Brazil. The mean age of the workers was 32.8 (SD ± 5.3) yrs. Their food intake was ascertained by the use of a 3-day dietary record, and their nutritional status was evaluated by their body mass index (BMI), both in winter and summer. Two-way ANOVA (shift and season) showed food consumption—measured in calories/24 h—was significantly higher in winter than summer (F(1.25) = 11.7; p < 0.001). No statistically significant differences were found among shifts (F(2.25) = 0.85; p < 0.44), and the interaction effect between shift and season was also not significant (F(2.25) = 0.15; p < 0.86). No seasonal difference in BMI was detected (Kruskal-Wallis test). Cosinor analyses showed circadian rhythmicity in calories consumed by morning (p < 0.01) as well as afternoon shift workers (p < 0.001), both in the winter and summer. Circadian rhythmicity in calories consumed by night workers was found only in summer (p < 0.01). The changes observed in the workers’ eating habits from one season to another and during the 24 h period show the need for further studies to help develop educational programs to improve the nutrition of shift employees taking into consideration shift schedule and season of the year when work is performed.

Satisfação no trabalho - uma breve revisão

Este artigo tem o objetivo de apresentar uma breve revisao sobre satisfacao no trabalho, analisando suas diferentes concepcoes. Associadas a essas concepcoes, tambem sao apresentadas caracteristicas do trabalho que interferem e determinam a satisfacao, bem como as consequencias da satisfacao e da insatisfacao no ambiente de trabalho.

Obstructive sleep apnea syndrome in truck drivers

OBJECTIVE To determine the prevalence of obstructive sleep apnea syndrome (OSAS), as well as to identify factors associated with a greater risk of developing OSAS, among truck drivers. METHODS The study population comprised 209 truck drivers (mean age, 38.8 years; 98.5% males) at two branches of a transportation company. The mean body mass index was 26.5 +/- 4.4 kg/m(2). The participants completed questionnaires regarding sociodemographic data, physical activity and OSAS. The prevalence of OSAS was estimated using the Berlin Questionnaire, associations between OSAS and the factors studied being assessed through univariate and multivariate regression analysis. RESULTS The prevalence of OSAS in the population was 11.5%. Of the 209 truck drivers, 72 (34.5%) reported having fallen asleep while driving and 81 (38.7%) reported snoring. The following variables were found to present statistically significant associations with OSAS: informal employment (OR = 0.27; p = 0.01); body mass index > 25 kg/m(2) (OR = 13.64; p = 0.01); and poor sleep quality (OR = 3.00; p = 0.02). CONCLUSIONS The prevalence of OSAS in this study was lower than that reported in other studies of truck drivers and yet higher that that observed for the general population. In addition, our results suggest that work characteristics, such as employment status, are associated with OSAS. These data show the relevance of considering work activity in studies of factors associated with OSAS.

Implementation of 12-hour shifts in a Brazilian petrochemical plant: impact on sleep and alertness.

A recent worldwide trend in chemical and petrochemical industries is to extend the duration of shifts. Optimization of the labor force to reduce costs is one reason to increase the length of working time in a shift. Implementation of 12h shifts is a controversial decision for managers and scientists. Literature reviews show alertness is lower during the nighttime hours, and sleep duration is reduced and worse during the daytime. The main objective of this study was to evaluate the impacts of 12h shifts on alertness and sleep. To evaluate the duration and quality of sleep and alertness during work, 22 male shift workers on a continuous rotating schedule at a petrochemical plant completed activity logs and estimated alertness using analog 10-cm scales for 30 consecutive days, three times (at 2h, 6h, and 10h of the shift) every work shift. Statistical tests (analysis of variance [ANOVA] and Tukey) were performed to detect differences between workdays and off days. The shift schedule was 2 days/3 nights/4 off days, followed by 3 days/2 nights/5 off days, followed by 2 days/2 nights/5 off days. Sleep duration varied significantly (p <. 001) among the work shifts and off days. Comparing work nights, the shortest mean sleep occurred after the second night (mean = 311.4 minutes, SD = 101.7 minutes), followed by the third night (mean = 335.3 minutes, SD = 151.2 minutes). All but one shift (sleep after the first work night) were significantly different from sleep after the first 2 workdays (p <. 002). Tukey tests showed no significant differences in sleep quality between workdays and nights, with the exception of sleep after the third day compared to sleep after night shifts. However, significant differences were detected between off days and work nights (p <. 01). ANOVA analysis showed borderline differences among perceived alertness during day shifts (p =. 073) and significant differences among the hours of theshifts(p =. 0005), especially when comparing the 2nd hour of the first day with the 10th hour of all the day shifts. There were no significant differences in perceived alertness during night work among the first, second, and third nights (p =. 573), but there were significant differences comparing the times (2nd, 6th, 10th hour) of the night shifts (p ≤. 001). The evaluation of sleep (duration and quality) and level of alertness have been extensively used in the literature as indicators of possible performance decrements at work. The results of this study show poorer sleep after and significantly decreased alertness during night work. Shifts of 12h are usually implemented for technical and economic reasons. These results point out the necessity of a careful trade-off between the financial and technical gains longer shifts might bring and the possible losses due to incidents or accidents from performance decrements during work. (Chronobiology International, 17(4), 521–537, 2000)

Irregular working times and metabolic disorders among truck drivers: a review

A number of studies to better understand the complex physiological mechanism involved in regulating body weight have been conducted. More specifically, the hormones related to appetite, leptin and ghrelin, and their association to obesity have been a focus of investigation. Circadian patterns of these hormones are a new target of research. The behaviour of these hormones in individuals subject to atypical working times such as shiftwork remains unclear. Shiftwork is characterized by changes in biological rhythms and cumulative circadian phase changes, being associated with high rates of obesity and metabolic syndrome. Truck drivers, who work irregular shifts, frequently present a high prevalence of obesity, which might be associated with work-related factors and/or lifestyle. In this context, the aim of this paper was to discuss the relationship of body mass index, appetite-related hormones and sleep characteristics in truck drivers who work irregular shifts compared with day workers.

Satisfação no trabalho e capacidade para o trabalho entre docentes universitários

The main aim of this study was to verify the correlation between job satisfaction and work ability among college educators. A quantitative approach was carried out in a cross-sectional design. The study included 154 educators, among them 50.6% were male and 40.4% female, with mean age of 39.25 years. Data collection included three questionnaires: 1. Socio-demographic and functional data; 2. Job satisfaction scale; 3. Work Ability Index -WAI. Job satisfaction and WAI showed a significant statistically correlation (r=0.23, p<0.01). It can be conclude that the increase of job satisfaction can improve the educators work ability.

Distúrbios psíquicos menores e condições de trabalho em motoristas de caminhão

OBJECTIVE To estimate the prevalence of minor psychiatric disorders and to identify associated stressors among truck drivers. METHODS A cross-sectional study was conducted with 460 truck drivers from a cargo transportation company of the Southern and Southeastern regions of Brazil, in 2007. Workers completed a questionnaire about sociodemographic, lifestyle and working conditions data. Working conditions were the independent variables, including occupational stressors, job satisfaction and job demand-control. The outcome evaluated was the occurrence of minor psychiatric disorders. Multiple and univariate logistic regression analyses were performed. RESULTS The prevalence of minor psychiatric disorders was 6.1%. The most frequently reported stressors were traffic congestion, tracking control and extended working hours. High job demand, low social support and extended daily working hours, as reported by drivers, were associated with minor psychiatric disorders. CONCLUSIONS Work involving extended working hours was associated with the occurrence of minor psychiatric disorders, both in the analysis of general working conditions and as a factor considered to be a stressor by drivers. Thus, regulation of working hours with focus on the limitation of the daily working hours is necessary to reduce the chance of developing minor psychiatric disorders in drivers.OBJETIVO: Estimar a prevalencia de disturbios psiquicos menores e identificar estressores associados entre motoristas de caminhao. METODOS: Estudo transversal conduzido com 460 motoristas de caminhao de uma transportadora de cargas das regioes Sul e Sudeste do Brasil, em 2007. Os trabalhadores preencheram questionario com dados sociodemograficos, estilos de vida e condicoes de trabalho. As variaveis independentes foram condicoes de trabalho, incluindo estressores ocupacionais, satisfacao e demanda-controle no trabalho. O desfecho avaliado foi a ocorrencia de disturbios psiquicos menores. Foram realizadas analises de regressao logistica univariada e multipla. RESULTADOS: A prevalencia de disturbios psiquicos menores foi de 6,1%. Os estressores mais citados foram congestionamentos, controle de rastreamento e jornada extensa de trabalho. A alta demanda no trabalho, o baixo apoio social e a jornada extensa diaria referidos pelos motoristas estiveram associados aos disturbios psiquicos menores. CONCLUSOES: O trabalho em jornadas extensas foi associado a ocorrencia de disturbios psiquicos menores, tanto na analise das condicoes gerais de trabalho quanto como fator referido como estressor pelos motoristas. A regulamentacao da jornada de trabalho com limitacao de horas de trabalho diario e, portanto, uma medida necessaria para a reducao da chance de desenvolvimento de disturbios psiquicos menores em motoristas.

A fresh look at the use of nonparametric analysis in actimetry

Actimetry has been used to estimate the sleep-wake cycle instead of the rest-activity rhythm. Although algorithms for assessing sleep from actimetry data exist, it is useful to analyze the rest-activity rhythm using nonparametric methods. This would then allow rest-activity rhythm stability, fragmentation and amplitude to be quantified. In addition, sleep and wakefulness efficiency can be quantified separately. These variables have been used in studies analyzing the effect of age, diseases and their respective treatments on human circadian rhythmicity. In this study, we carried out a comprehensive analysis of the main results from published articles and devised a functional model of interaction among the several components involved in generating the sleep-wake cycle. The nonparametric variables render it possible to infer the main characteristics of circadian rhythms, such as synchronization with a zeitgeber, and its amplitude and robustness.