Ruth Liane Henn

Impact of nightshift work on overweight and abdominal obesity among workers of a poultry processing plant in southern Brazil.

The authors examined the associations of shiftwork with overweight and abdominal obesity through a cross-sectional study of 1206 employees 18 to 50 yrs of age who were working on a production line in a poultry processing plant. Night-shift workers (n = 800) were considered exposed, whereas day shiftworkers (n = 406) were considered nonexposed. Overweight was defined as a body mass index ≥25 kg/m2 and abdominal obesity as a waist circumference ≥88 cm in women and ≥102 cm in men. The mean age of the workers was 30.5 yrs (standard deviation = 8.7 yrs), and 65.2% were women. Nightshift workers compared to dayshift workers showed higher prevalences of overweight (42.2% vs. 34.3%; p = .020) and abdominal obesity (24.9% vs. 19.5%; p = .037). After adjusting for sociodemographics, parental overweight status, behavioral characteristics, and sleep characteristics, including hours of sleep, the prevalence ratios for overweight and abdominal obesity were 1.27 (95% confidence interval [ CI]: 1.00–1.61) and 1.45 (95% CI: 1.10–1.92), respectively, for the nightshift workers compared to the dayshift workers. A consistent finding in our study was the independent contribution of night shiftwork to overweight and abdominal obesity among Brazilian workers. Further studies are needed to understand the biological mechanisms involved and the complex behavioral and social adaptations experienced by night-shift workers. (Author correspondence: mtolinto@gmail.com)

Development and validation of a food frequency questionnaire (FFQ-Porto Alegre) for adolescent, adult and elderly populations from Southern Brazil

This study assessed the validity of a food frequency questionnaire (FFQ-Porto Alegre), covering 135 food items, in comparison with the average of two consecutive 24-hour dietary recall questionnaires for adolescents, adults, and elderly who were randomly selected from a population-based survey. The Pearson correlation coefficients and cross-classification by quartiles of intake were used. The nutrients were log transformed and energy adjusted. The mean of adjusted de-attenuated correlation coefficient for adolescents was 0.44 and ranged from 0.18 (zinc) to 0.69 (folate) and for adult and elderly participants they were, respectively, 0.42, ranging from 0.16 (iron) to 0.73 (energy) and 0.52, ranging from 0.25 (vitamin E) to 0.84 (energy). The average classification percentage into the same or adjacent quartile for the two methods was 74.6% for adolescents, 74.9% for adults, and 81.2% for the elderly population. The FFQ showed fair relative validity for adolescents and adults, and may be used to study the dietary determinants of obesity and non-transmissible diseases in epidemiological surveys.

Avaliação de reprodutibilidade e validade de um questionário de freqüência alimentar em adultos residentes em Porto Alegre, Rio Grande do Sul, Brasil

The reproducibility and validity of a Food Frequency Questionnaire (FFQ) was evaluated in 83 adults living in a State capital in southern Brazil. The reproducibility and validity were tested with intra-class correlation coefficients (ICC). Mean nutrient intakes from three 24-hour dietary recalls (24hDR) were compared to mean intakes from each FFQ (FFQ1 and FFQ2), adjusted for energy intake and within-person variation. Nutrients were categorized into quartiles and assessed using weighted kappa statistics. Mean ICC for the test-retest FFQ ranged from 0.44 (95%CI: -0.19-0.76) to 0.83 (95%CI: 0.72-0.90) for energy-adjusted carbohydrate and vitamin C intakes, respectively. Mean ICC, energy-adjusted and corrected for within-person variability, ranged from 0.23 (95%CI: -0.22-0.61) to 0.86 (95%CI: 0.21-1.16) for vitamin A and lipids for the FFQ1, and 0.50 (95%CI: -0.16-0.91) to 0.95 (95%CI: 0.79-1.05) for vitamin A and energy for the FFQ2. For the FFQ1, calcium showed the lowest weighted kappa value (0.10; 95%CI: 0.00-0.26), while vitamin C (0.38; 95%CI: 0.23-0.53) and total energy (0.38; 95%CI: 0.24-0.52) had the highest weighted kappa for the FFQ2. The FFQ showed good reproducibility and reasonable relative validity.

Seasonal effect on nutrient intake in adults living in Southern Brazil

The objective of this study was to investigate the effect of seasonality on nutrient intake in healthy adults from the southernmost metropolitan area of Brazil. The dietary intake (24-hour dietary recall on six different days) in a sample of 162 adults (114 women), aged 20 to 69, was obtained during the year 2007. The nutrient intake was averaged for each season and adjusted for energy intake using the residual method. The effect of season on energy, macro and micro-nutrient intake was investigated based on the Generalized Estimate Equations (GEE) model. There were statistically significant differences between seasons for carbohydrate and total fat intake after controlling for gender, age, education, and interactions. In summer carbohydrate intake was higher than other seasons while the total fat intake was lower. These findings highlight the importance of considering seasonal variations not only for evaluating dietary intake but also nutrition and public health policy recommendations, particularly in adult populations living in temperate regions.

Associação entre aspectos psicossociais e excesso de peso referido em adultos de um município de médio porte do Sul do Brasil

The objective of this study was to investigate the association between psychosocial factors and self-reported overweight. A cross-sectional study was carried out with 1,100 adults in a Brazilian city. Structured interviews were conducted using a standard pre-tested questionnaire. Overweight was self-reported by participants and defined as body mass index (BMI) > 25kg/m². Psychosocial factors were quality of life (WHO-8: EUROHIS) and social support (Medical Outcomes Study). Crude and adjusted prevalence ratios (PR) were obtained by modified Poisson regression. After controlling for socio-demographic and behavioral variables, prevalence of overweight among individuals reporting low quality of life and low social support was 19% (PR = 1.19; 95%CI: 1.03-1.38) and 12% (PR = 1.12; 95%CI: 0.96-1.31), respectively, and was higher in those reporting high/moderate quality of life and high/moderate social support, respectively. The findings suggest that psychosocial factors can play a role in self-assessment of overweight.

Sleep deprivation and obesity in shift workers in southern Brazil

OBJECTIVE The objective of our study was to explore the association between sleep deprivation and obesity among shift workers. DESIGN A cross-sectional study was conducted. Obesity was defined as BMI ≥30 kg/m2. Time of sleep was categorized as: >5 h of continuous sleep/d; ≤5 h of continuous sleep/d with some additional rest (sleep deprivation level I); and ≤5 h of continuous sleep/d without any additional rest (sleep deprivation level II). Sociodemographic, parental and behavioural variables were evaluated by means of a standardized pre-tested questionnaire. Potential confounding factors were controlled for in the multivariable model. SETTING A poultry-processing plant in southern Brazil. SUBJECTS Nine hundred and five shift workers (63 % female). RESULTS Obesity was more prevalent in the participants who were female, aged 40 years and older, who had less schooling and reported excess weight in both parents. Sleep deprivation levels I and II were associated with increased income, number of meals consumed throughout the day and nightshift work. All of the workers who exhibited a degree of sleep deprivation worked the night shift. After controlling for potential confounding factors, the prevalence ratios of obesity were 1·4 (95 % CI 0·8, 2·2) and 4·4 (95 % CI 2·4, 8·0) in the workers with sleep deprivation levels I and II, respectively, compared with the reference group. CONCLUSIONS These results show a strong association between sleep deprivation and obesity in shift workers and that sleep deprivation may be a direct consequence of working at night.

Development of a food frequency questionnaire in a probabilistic sample of adults from Niterói, Rio de Janeiro, Brazil

With the purpose of generating a list of foods for a food-frequency questionnaire, data from 24h dietary recalls on a typical day from a probabilistic sample of 1,724 adults of Niterói, Rio de Janeiro, Brazil, were analyzed. The frequency of food intake, the total intake of energy and macronutrients and the relative contribution of each food item to total energy and macronutrient intake were calculated. The most frequently reported food items (> 50% of adults) were rice, coffee, beans, refined canesugar, and bread. Whole milk was consumed more frequently then skimmed milk or semi-skimmed milk. Beef was consumed by more adults than chicken, pork or fish. Approximately 90% of energy and macronutrients intake was explained by 65 food items. The list of food items generated in the present analysis is similar to those found in other samples of adults from urban areas in Brazil. It may be possible to generate a core list of common foods with addition of regional foods to be used nationally in urban areas of the country.

Seasonal variation in food intake and the interaction effects of sex and age among adults in southern Brazil.

Background/objectives:Because studies have evidenced variations in nutrient intake, further investigation of the interaction between demographic characteristics and the seasons is necessary. We aimed to test the differences in food intake throughout the seasons and the interaction between the seasons and sex and age.Subjects/methods:This study included 273 individuals. Food intake was evaluated with 24-hour dietary recalls, and the reported food items were sorted into food groups. We performed the test on the differences in intake of food groups throughout the seasons with repeated measures and on the interaction effect by using the Generalized Estimate Equation.Results:Intake of fruits and natural fruit juices and sweetened beverages was lower, whereas that of grains and derivatives was higher in the winter. The intake of leafy vegetables and fish and seafood was lower in the autumn. The consumption of coffee and eggs was higher in the spring. Intake of chocolate powder and sugar, salt and lean poultry was higher in the winter. The variation in consumption of grains and derivatives, eggs, fatty poultry and processed meat over the seasons was more likely to be modified by sex. Age interacted with the seasons for leafy vegetables, beans and lentils, lean beef, lean poultry, low fat milk and light yogurt, vegetable oil and unsalted margarine, chocolate powder and sugar and processed meat.Conclusions:This study shows that food intake may change seasonally and that seasonal variation depends on sex and age, which might aggregate a specific co-variation component.

Variacao sazonal na ingestao alimentar de adultos de Niteroi, Rio de Janeiro

The measurement of usual food intake (FI) is necessary to accurately establish the relationship between diet and disease. In most studies data are collected at one particular time of the year, which may influence the interpretation of the results. The purpose of this study was to investigate the effect of seasonality on FI in a sample of adults from Niterói, RJ, Brazil. A total of 102 healthy subjects (69 women) aged between 20 and 69 years were interviewed to obtain six 24-hour dietary recalls, three in summer and three in winter. In both seasons, the intake of energy (EI) and 23 nutrients was determined and the percent of subjects who met the recommendations for the nutrients were computed. The data of FI were deattenuated considering the within-person variability and adjusted for energy. The intake of energy and some nutrients were significantly different between men and women. EI did not differ between seasons, for both sexes, but the intake of macro and micronutrients was different. The results of this study suggest that the seasonality in the measurement of FI should be considered in order to improve the methods and instruments used in population dietary surveys.

Metabolic syndrome in fixed-shift workers

OBJECTIVE To analyze if metabolic syndrome and its altered components are associated with demographic, socioeconomic and behavioral factors in fixed-shift workers. METHODS A cross-sectional study was conducted on a sample of 902 shift workers of both sexes in a poultry processing plant in Southern Brazil in 2010. The diagnosis of metabolic syndrome was determined according to the recommendations from Harmonizing the Metabolic Syndrome. Its frequency was evaluated according to the demographic (sex, skin color, age and marital status), socioeconomic (educational level, income and work shift), and behavioral characteristics (smoking, alcohol intake, leisure time physical activity, number of meals and sleep duration) of the sample. The multivariate analysis followed a theoretical framework for identifying metabolic syndrome in fixed-shift workers. RESULTS The prevalence of metabolic syndrome in the sample was 9.3% (95%CI 7.4;11.2). The most frequently altered component was waist circumference (PR 48.4%; 95%CI 45.5;51.2), followed by high-density lipoprotein. Work shift was not associated with metabolic syndrome and its altered components. After adjustment, the prevalence of metabolic syndrome was positively associated with women (PR 2.16; 95%CI 1.28;3.64), workers aged over 40 years (PR 3.90; 95%CI 1.78;8.93) and those who reported sleeping five hours or less per day (PR 1.70; 95%CI 1.09;2.24). On the other hand, metabolic syndrome was inversely associated with educational level and having more than three meals per day (PR 0.43; 95%CI 0.26;0.73). CONCLUSIONS Being female, older and deprived of sleep are probable risk factors for metabolic syndrome, whereas higher educational level and higher number of meals per day are protective factors for metabolic syndrome in fixed-shift workers.