Association between chronotype, food intake and physical activity in medical residents.

An individual's chronotype is a trait which reflects his/her diurnal preferences for the times of rest and activities, and displays a continuum from morningness to eveningness. Studies have shown that eveningness tends to be associated with a less healthy lifestyle, including increased likelihood of developing obesity. In this study, we examined the relationship between chronotype and food intake, physical sleep and activity in 72 resident physicians (52 women and 20 men). Assessments included chronotype evaluation by the Horne and Ostberg Morningness-Eveningness questionnaire (MEQ); food intake pattern through a self-administered food diary that was kept over the course of 3 non-successive days; physical activity level, using the Baecke questionnaire (BQ); sleep quality and quantity using the Pittsburgh Sleep Quality Index (PSQI); and sleepiness, Epworth Sleepiness Scale (ESS). Linear regression analyses, after adjustments for age, sex, body mass index (BMI), hours of additional work per week ESS and total physical activity score, showed that the chronotype score was negatively associated with cholesterol (coefficient = -0.24; p = 0.04), sweets (coefficient = -0.27, p = 0.03) and vegetables (coefficient = -0.26; p = 0.04) intakes. Following the same statistical adjustments, the chronotype score was positivity associated with leisure-time index (coefficient = 0.26, p = 0.03) and BQ total score (coefficient = 0.27, p = 0.03). We concluded that most issues related to nutrition problems and unhealthy lifestyle were associated with scores indicative of eveningness. These findings emphasize the importance of assessing an individual's chronotype when examining feeding behavior.

Nutritional status and eating habits of bus drivers during the day and night.

The aim of this study was to compare anthropometry and food intake patterns in bus drivers working during the day and night. One hundred and fifty males (81 night workers and 69 day workers) participated in the study. Dietary intake was assessed using a validated semi-quantitative food frequency questionnaire. Measurements of height, weight, waist circumference (WC), systolic and diastolic blood pressure, blood glucose, and lipid profile were obtained. A significant difference between groups was observed for mean WC (98.5 ± 10.7 cm in day workers versus 103.2 ± 9.7 cm in night workers; p = 0.005). Night workers had higher prevalence of being overweight and obese (BMI ≥ 25 kg/m(2)) than day workers (78.2% day workers versus 90.2% night workers; p = 0.004) and increased WC (>94 cm) (72.4% day workers versus 86.4% night workers; p = 0.03). Significant differences were found for meat consumption (2.3 servings ±0.9 for night workers versus 2.0 servings ±0.7 day workers, p = 0.04) and fruit intake (0.9 servings ±0.4 for night workers versus 0.7 servings for day workers ±0.5; p = 0.006). Night workers had a lower intake of vegetables than recommended compared to day workers (100 versus 92.7%, respectively, p = 0.01) and higher intake of oil (40.7 versus 24.6%, p = 0.03). Multivariate logistic regression analysis indicated that night work was associated with being overweight (OR = 2.94, 95% IC: 1.14-7.66, p = 0.03) and abnormal values of WC (OR = 2.82, 95% IC: 1.20-6.69, p = 0.009) after adjusting for potential confounders. It is concluded that night workers had a higher prevalence and risk of being overweight/obese and increased WC compared with day workers. Night workers also presented a higher proportion of inappropriate intakes of food groups when compared to day workers, even though both groups were eating poor diets. These results demonstrate the need of lifestyle-intervention programs in these workers.

Sleep pattern is associated with adipokine levels and nutritional markers in resident physicians.

Shift work and long hours of work are common in medical training and have been associated with a higher propensity for developing nutritional problems and obesity. Changes in leptin and ghrelin concentrations - two hormones that contribute importantly to the central regulation of food intake - are poorly described in this population. The aim of this study was to identify possible negative associations between sleep patterns, nutritional status and serum levels of adipokines. The study included 72 resident physicians (52 women and 20 men) who underwent the following assessments: nutritional assessment (3-day dietary recall evaluated by the Adapted Healthy Eating Index), anthropometric variables, fasting metabolism, physical activity level, sleep quality and sleepiness. Resident physicians with poor sleep quality reported greater weight gain after the beginning of residency (5.1 and 3.0 kg, respectively; p = 0.01) and higher frequency of abnormal waist circumference (44.2 and 17.6%, respectively; p = 0.04) than those with better sleep quality. Mean ghrelin concentration was greater in volunteers with poor sleep quality (64.6 ± 67.8 and 26.2 ± 25.0 pg/mL, respectively; p = 0.04). Women identified as having excessive daytime sleepiness had lower levels of leptin (9.57 ± 10.4 ng/mL versus 16.49 ± 11.4 ng/mL, respectively; p = 0.03) than those without excessive sleepiness. Furthermore, correlations were found between hours of additional work per week and: intake of cereals, bread and pasta (r = 0.22, p = 0.01); intake of servings of fruits (r = -0.20; p = 0.02) and beans (r = -0.21; p = 0.01); and global score for Adapted Healthy Eating Index (r = -0.23; p = 0.008; Table 3). The sleep quality total score correlated with servings of beans (r = -0.22; p = 0.01) and servings of oils (r = 0.23; p = 0.008). Significant correlations were found between mean of time of sleep and servings of cereals, bread and pasta (r = 0.20; p = 0.02), servings of meat (r = -0.29; p = 0.02) and cholesterol levels (r = 0.27; p = 0.03). These observations indicate that sleep patterns and long working hours of resident physicians are negatively associated with biological markers related to central food control, the lipid profile, cholesterol levels and eating healthy foods. These factors may predispose these shift workers to become overweight and develop metabolic disorders.

Dietary patterns, metabolic markers and subjective sleep measures in resident physicians.

Shiftwork is common in medical training and is necessary for 24-h hospital coverage. Shiftwork poses difficulties not only because of the loss of actual sleep hours but also because it can affect other factors related to lifestyle, such as food intake, physical activity level, and, therefore, metabolic patterns. However, few studies have investigated the nutritional and metabolic profiles of medical personnel receiving training who are participating in shiftwork. The aim of the present study was to identify the possible negative effects of food intake, anthropometric variables, and metabolic and sleep patterns of resident physicians and establish the differences between genders. The study included 72 resident physicians (52 women and 20 men) who underwent the following assessments: nutritional assessment (3-day dietary recall evaluated by the Adapted Healthy Eating Index), anthropometric variables (height, weight, body mass index, and waist circumference), fasting metabolism (lipids, cortisol, high-sensitivity C-reactive protein [hs-CRP], glucose, and insulin), physical activity level (Baecke questionnaire), sleep quality (Pittsburgh Sleep Quality Index; PSQI), and sleepiness (Epworth Sleepiness Scale; ESS). We observed a high frequency of residents who were overweight or obese (65% for men and 21% for women; p = 0.004). Men displayed significantly greater body mass index (BMI) values (p = 0.002) and self-reported weight gain after the beginning of residency (p = 0.008) than women. Poor diet was observed for both genders, including the low intake of vegetables and fruits and the high intake of sweets, saturated fat, cholesterol, and caffeine. The PSQI global scores indicated significant differences between genders (5.9 vs. 7.5 for women and men, respectively; p = 0.01). Women had significantly higher mean high-density lipoprotein cholesterol (HDL-C; p < 0.005), hs-CRP (p = 0.04), and cortisol (p = 0.009) values than men. The elevated prevalence of hypertriglyceridemia and abnormal values of low-density lipoprotein cholesterol (LDL-C; >100 mg/dL) were observed in most individuals. Higher than recommended hs-CRP levels were observed in 66% of the examined resident physicians. Based on current recommendations, a high prevalence of low sleep quality and excessive daytime sleepiness was identified. These observations indicate the need to monitor health status and develop actions to reassess the workload of medical residency and the need for permission to perform extra night shifts for medical residents to avoid worsening health problems in these individuals.