Fatores associados à baixa duração do sono em adolescentes

Screen time is negatively associated with sleep quality and duration only in insufficiently active adolescents: A Brazilian cross-sectional school-based study

Background

Time spent on screen devices affects sleep quality and duration leading to several health impairments in youth. Although physical activity (PA) benefits sleep patterns and decreases screen time in adolescents, it is unclear whether the relationship between sleep quality/duration and screen time could be influenced by PA levels.

Objective

To analyze the association between sleep quality and duration with screen time in Brazilian adolescents according PA levels.

Methods

The sample included 1010 adolescents aged 13.2 ± 2.4 years (n = 556 females - 55 % of the sample). Sleep quality and sleep duration, and PA were assessed by Mini Sleep and Baecke questionnaires, respectively. Participants in the highest quartile were classified as physically active. Screen time was analyzed by the self-reported number of hours spent on different screen devices (i.e., television, computer, videogame, and cellphone/tablet). Participants in the highest tertile were classified as having high screen time. Sex, age, and body mass index were considered covariates in binary logistic regression models.

Results

Poor sleep quality was observed in 52.3 % of the sample, whereas 46.6 % reported sleeping less than eight hours/day. High screen time was associated with poor sleep quality (OR = 1.45; 95 %CI = 1.01-2.12) and insufficient sleep duration (OR = 1.52; 95 %CI = 1.01-2.03) in adolescents insufficiently active. There were no associations between screen time and sleep parameters in active adolescents.

Conclusion

High screen time was associated with poor sleep quality and insufficient sleep duration only in insufficiently active adolescents. These results suggest that high PA levels may contribute to improving sleep patterns in pediatric population.

Association between Sleep Timing, Being Overweight and Meal and Snack Consumption in Children and Adolescents in Southern Brazil

Sleep timing is one of the dimensions of sleep that refers to the time of day when sleep occurs. It has been included in sleep-related research because of the potential associations between being overweight and the consumption of meals and snacks. This cross-sectional study aimed to investigate associations between sleep timing, meal and snack consumption and weight status in 1333 schoolchildren aged 7-14 years. The midpoint of sleep was used as a sleep timing measure obtained by the midpoint between bedtime and wake-up time, classified as Early, Intermediate, and Late. Schoolchildren in the Early group were less likely to be overweight (OR: 0.83, 95% CI 0.69; 0.99), and had higher odds of mid-morning snack consumption (OR: 1.95, 95% CI 1.56; 2.44) and lower probability to consume an evening snack (OR: 0.75, 95% CI 0.59; 0.94) compared with the Intermediate group. The Late group had lower odds of mid-morning snack consumption (OR: 0.67, 95% CI 0.55, 0.80) than the Intermediate group. The consumption of mid-morning and evening snacks was associated with the Early and Late midpoints of sleep. These results suggest that bedtime and wake-up time are relevant to consuming meals and snacks and may also be related to a greater probability of being overweight in children and adolescents.

Is sleep time associated with handgrip strength in adolescents from the 1997/1998 São Luís Birth Cohort?

This article aims to analyze the association between sleep time and handgrip strength in adolescents belonging to the 1997/1998 São Luís Birth Cohort. This was a cross-sectional study nested in a birth cohort study. One thousand two hundred sixty-nine individuals (18 and 19 years) wore an Actigraph® GTX3+ accelerometer on their wrist 24 hr/day for 7 consecutive days. Handgrip strength was measured using a digital hand dynamometer. We used directed acyclic graphs (DAG) to identify confounding variables. This sample of adolescents was mostly composed of men, with brown skin color, economic class C, which did not work, did not consume alcohol, did not smoke, and never used drugs. The mean value of handgrip strength was 28.2 (±9.3) kgf, and the mean of sleep time was 6 (±1.0) hours per day. The crude analysis showed an association between sleep time and muscle strength. An increase of one hour of sleep reduced the handgrip strength by 1.95 kgf (95%CI:-2.51;-1.39). However, after adjustment for confounders, the association was not maintained (β:-0.07; 95%CI:-0.48;0.36). Sleep time is not associated with handgrip strength in adolescents in São Luís.

Social, Biological and Behavioral Factors Associated with Social Jet Lag and Sleep Duration in University Students from a Low Urbanized City

Introduction

Sleep deprivation and social jet lag are observed in college students from highly urbanized cities. However, does these consequences also present in college students from a low urbanization city?

Objective

To evaluate the prevalence and social, biological and behavioral factors associated with sleep deprivation and social jet lag in university students from a low urbanized city of Brazil.

Methods

A total of 298 university students participated in the study through application of the Health and Sleep and the Munich Chronotype Questionnaires. Multiple linear regression with stepwise-forward method was adopted to assess the associations of the factors with the outcome variables.

Results

Doing leisure activities (LA) (B = 23.24) and academic demand (AD) before bedtime (B = 19.51), both on the weekend, and doing household chores (HC) before bedtime (B = 17.61) in the week were associated with an increase in social jet lag, while stimulating drinks (SD) were associated with a decrease (B = −15.17). Shorter sleep duration in the week was related to chronotype (B = −0.56), male (B = −26.51), doing LA (B = −27.63), poor perception about sleeping place (PPSP) (B = −43.02) and daily commute (B = −68.97). The shorter sleep duration in the weekend was associated to male (B = −36.36), PPSP (B = −58.16), have recreational and religious activities (B = −31.11), doing LA (B = −25.10) and AD (B = −23.60). Just chronotype was associated with longer sleep duration in the weekend (B = 0.25).

Conclusion

University students from a low urbanized city present social jet lag, shorter sleep duration on school days and longer sleep duration on free days as a result of biological and social factors, and mostly behavioral factors.

Is chronotype associated with dietary intake and weight gain during pregnancy? A prospective and longitudinal study

OBJECTIVES

The effects of chronotype on dietary intake and weight gain during pregnancy have not been addressed in the literature. The aim of this study was to analyze the effect of chronotype on eating patterns, energy, and macronutrient intake and distribution, as well as weight gain during pregnancy.

METHODS

This was a prospective cohort study carried out with 100 pregnant women in the first, second, and third gestational trimesters. Dietary intake was assessed by three 24-h dietary recalls in each trimester, totaling nine recalls. Energy and macronutrient intake and distribution were evaluated at meals throughout the day. Chronotype was derived from midsleep time on free days, and the scores obtained were categorized into tertiles. Recommendations from the Institute of Medicine were used to assess the adequacy of weight gain. Generalized estimating equation models were used to determine the effects of chronotype and gestational trimester on eating patterns, daily energy, macronutrient distribution, and weight gain.

RESULTS

Pregnant women with values for midsleep time on free days indicative of eveningness have breakfast later and also have higher energy and carbohydrate intake at dinner than "morning" women. Pregnant "morning" women showed better diet quality in terms of milk and dairy and saturated fat. Also, despite the tendency for all tertiles to gain excess weight during pregnancy, we found that pregnant women with a tendency to eveningness had worse adequacy of gestational weight gain in the third trimester than "morning" women (2.24 ± 0.25 versus 1.22 ± 0.14, P < 0.001).

CONCLUSION

Pregnant women with a tendency to eveningness consume breakfast later in the day and exhibit greater consumption of energy and carbohydrates in the evening, as well as a worse standard of gestational weight gain in the third trimester. Our results emphasize the importance of considering chrononutrition variables in prenatal nutritional guidelines to promote maternal and fetal health.

Is napping related with health-related behaviors and sleep habits among adolescents? A population-based study

INTRODUCTION

Changes in sleep quality and quantity occur in adolescence and can lead to the compensatory behavior of daytime napping.

OBJECTIVE

Analyze factors related to napping in adolescents.

METHODS

A population-based cross-sectional study was conducted with 1022 adolescents who participated in the 2014-2015 Health Survey of the city of Campinas, state of São Paulo, Brazil. Napping was the dependent variable. Sociodemographic characteristics, living habits, health-related behaviors, feelings of loneliness, satisfaction with life and nocturnal sleep habits were the independent variables. Data analysis was performed using Rao-Scott chi-square test, unpaired Student's t-test and Poisson regression analysis; p < 0.05 was considered significant. The software STATA was used for analysis.

RESULTS

Mean participant age was 14.6 years (SD: 2.7; range: 10 to 19 years). Males accounted for 50.9% of the sample and 55.7% had white skin color. A total of 40.5% reported napping. Napping was more common in females (p = 0.006), the 14-to-17-year-old age group (p = 0.002), those who took medications in the previous 15 days (p = 0.001), those who were insufficiently active (p = 0.036), those who reported little or no satisfaction with life (p = 0.008) and those who woke up in bad mood (p = 0.004). Adolescents who napped also reported shorter sleep during the week (p < 0.001) and a perceived greater need for sleep (p < 0.001).

CONCLUSION

The prevalence of napping among the adolescents was independently associated with shorter average sleep, a perceived greater need for sleep than that obtained and waking up in a bad mood.

Short and long sleep duration and associated factors in pre-adolescence and early adulthood: evidence from the 1993 Pelotas birth cohort study

OBJECTIVE

The objective of the present study was to investigate the associated factors with short and long sleep duration at ages 11 (pre-adolescence) and 22 years old (early adulthood).

METHODS

Participants of the 1993 Pelotas birth cohort with self-reported sleep records at 11 (n = 4442) and 22 (n = 3800) years were included. The total sleep time duration was categorised as short (<9 h for 11 years and <7 h for 22 years), long (>11 for 11 years and >9 for 22 years) and recommended according to the National Sleep Foundation criteria. Multinomial regression analyses were applied according to a hierarchical approach in order to investigate the associated factors with sleep duration patterns. All analyses were stratified by sex.

RESULTS

Higher income was associated with higher odds of short sleep duration in 11-year-old boys [OR = 1.54 (CI95%: 1.08; 2.19)] and girls [OR = 1.45 (CI95%: 1.03; 2.06)] and also with lower odds of long sleep duration in both ages. At 22 years, common mental health disorders were associated with higher odds of short sleep duration in both men [OR = 1.56 (CI95%: 1.18; 2.06)] and women [OR = 1.48 (CI95%: 1.11; 1.99)]. Sleep duration was also related to screen time and physical activity showing different association patterns according to sex and age.

CONCLUSIONS

Different factors may be associated with sleep duration patterns in pre-adolescence and early adulthood. Our results emphasise the importance of considering stratification analyses to identify associated factors with sleep duration since they may vary according to age and sex.

Relationship between sleep duration and TV time with cardiometabolic risk in adolescents

Objective

To verify the association between sleep duration and television time with cardiometabolic risk and the moderating role of age, gender, and skin color/ethnicity in this relationship among adolescents.

Methods

Cross-sectional study with 1411 adolescents (800 girls) aged 10 to 17 years. Television time, sleep duration, age, gender, and skin color/ethnicity were obtained by self-reported questionnaire. Cardiometabolic risk was evaluated using the continuous metabolic risk score, by the sum of the standard z-score values for each risk factor: high-density lipoprotein cholesterol, triglycerides, glycemia, cardiorespiratory fitness, systolic blood pressure, and waist circumference. Generalized linear regression models were used.

Results

There was an association between television time and cardiometabolic risk (β, 0.002; 95% CI, 0.001; 0.003). Short sleep duration (β, 0.422; 95% CI, 0.012; 0.833) was positively associated with cardiometabolic risk. Additionally, age moderated the relationship between television time and cardiometabolic risk (β, − 0.009; 95% CI, − 0.002; − 0.001), suggesting that this relationship was stronger at ages 11 and 13 years (β, 0.004; 95% CI, 0.001; 0.006) compared to 13 to 15 years (β, 0.002; 95% CI, 0.001; 0.004). No association was found in older adolescents (β, 0.001; 95% CI, − 0.002; 0.002).

Conclusions

Television time and sleep duration are associated with cardiometabolic risk; adolescents with short sleep have higher cardiometabolic risk. In addition, age plays a moderating role in the relationship between TV time and cardiometabolic risk, indicating that in younger adolescents the relationship is stronger compared to older ones.

Short Sleep Duration and Extremely Delayed Chronotypes in Uruguayan Youth: The Role of School Start Times and Social Constraints

During adolescence, biological, psychosocial, and contextual factors converge in a “perfect storm” and have been put forward to explain the delay in chronotype observed at this age and the prevalence of disrupted sleep. This study provides evidence to support that chronotype and sleep patterns (particularly sleep duration) are socially constrained and to identify novel significant social predictors. Uruguayan public school activities are arranged in up to 4 shifts, creating a natural experiment to examine the effect of school timing on questionnaire-based assessments of sleep and chronotype. In this study, 268 high school students (15-18 years old) who attended school either on morning (0730 to 1130 h) or afternoon shifts (1130 h to 1530 h) responded to an adapted School Sleep Habits Survey. Students attending afternoon shifts had later chronotypes (a 1.5-h later midpoint of sleep on free days adjusted for sleep debt) than those attending the morning shift. Besides shift, evening social activities (including dinner time) were further identified as key predictors of late chronotypes, whereas age and gender were not. Sleep on school days was overall advanced and reduced with respect to weekends, and these effects were stronger in morning-shift students. Weekend sleep duration was similar between shifts, which probably caused the prevalence of reduced sleep durations (average weekly sleep duration, SDweek <8 h) to be higher in morning-shift students (almost 80%) than in afternoon-shift ones (34%). Reduced sleep duration was significantly higher in morning-shift students. In addition, age, chronotype, and dinner time became relevant determinants of sleep deficit only in the morning-shift students. Besides the important social constraint of early school start time, this is the first study to confirm the significance of other types of social pressures on both adolescents’ chronotype and sleep deficit, which can be useful as potential new targets for effective policies to protect adolescent sleep.

Association of sleep quality with sociodemographic factors and lifestyle in adolescents from southern Brazil

BACKGROUND

Good sleep quality is an essential component for growth, development, and physical and mental health of the individual, in addition to being a positive indicator of health and well-being. The objective of this study was to estimate the prevalence of poor sleep quality and to identify the association of poor sleep quality with sociodemographic factors, lifestyle, weight status, and associated aerobic fitness in adolescents.

METHODS

This study included 1110 students aged 14-19 years from city of São José/SC, Brazil. Sleep quality of the subjects was assessed using a questionnaire and classified as adequate and low. Independent variables were gender, age, monthly household income, maternal education, school shift, global physical activity, proper diet, screen time, sleeping hours of full week, sleeping hours of weekdays, sleeping hours of weekends, weight status, and aerobic fitness. Binary logistic regression was used to estimate odds ratios and confidence intervals of 95%.

RESULTS

Prevalence of poor sleep quality was 60.4%. More likely to have poor sleep quality were identified in female students (OR 1.68, 95% CI 1.11-2.55), whose mothers had higher levels of education (OR 1.44, 95% CI 1.20-1.73) and low aerobic fitness (OR 1.80, 95% CI 1.02-3.19).

CONCLUSION

Adolescents who were most likely to report poor sleep quality were female, those whose mothers had a higher educational level and had low aerobic fitness. Students with sedentary risk behavior were less likely of reporting poor sleep quality.

Sociodemographic and behavioral characteristics of obese students with sleep problems in Southern Brazil

ABSTRACT Objective This study estimated the combined prevalence of insufficient number of hours of sleep per day and excess body adiposity among young students. The sociodemographic and behavioral characteristics associated with this concurrent health conditions were investigated. Methods This is a cross-sectional school-based study of 975 participants aged 11-14 years in Florianópolis, Santa Catarina state, Brazil. Body adiposity was assessed based on tricipital and subscapular skinfold measurements and classified according to Lohman. The total number of hours of sleep per day was reported by the students’ parents/guardians, and it was classified as follows: as <8 hours per day and ≥8 hours per day. Data on sociodemographic characteristics, food consumption, and physical activity were collected using a self-administered questionnaire. The chi-square test and multinomial logistic regression with a 5% significance level were used to evaluate the association between the variables. Results The combined prevalence of insufficient number of hours of sleep per day and excess body adiposity was 25.1% (CI95%:20.7-29.9). The sociodemographic and behavioral factors predictive of these conditions were as follows: 13-14 year age group and household monthly income in the intermediate tertile. Conclusion The concurrent presence of insufficient sleep and excess body adiposity was found in a little more than a quarter of the students investigated. The population subgroups belonging to the 13-14 year age group and intermediate tertile of income were more likely to have concurrent insufficient number of hours of sleep per day and excess body adiposity.

Factor structure of the Brazilian version of Pediatric Daytime Sleepiness Scale

The present study aimed to analyze the construct validity of the Pediatric Daytime Sleepiness Scale (PDSS) for the evaluation of the daytime sleepiness construct in adolescents through confirmatory factorial analysis. The cross-sectional study was carried out with a sample of 773 adolescents aged 14 to 19 years, enrolled in the state schools of Paranaguá, Paraná, Brazil. We investigated the sex, age, school year, study shift, occupational status, socioeconomic level and daytime sleepiness. The PDSS questions were not normal (p <0.001) and the mean total score was 14.87 (5.62). With Schwarz's BIC adjustment indicators = 142,389 and Akaike's AIC = 105,389, the model reached the criteria of the global adjustment indicators of the model in the confirmatory analysis, in which RMSEA = 0.020; CFI = 0.986; TLI = 0.977; SRMR = 0.021, with 17 degrees of freedom, KMO = 0.8504 and Cronbach's Alpha = 0.737, with three correlations. We conclude that the construct validity of the PDSS remains valid and confirms its factor structure with only one factor. Thereby, it was verified that the operationalization of the construct sleepiness of adolescents through this scale is adequately conceptualized to the behavior of the age group.

Proposal of cutoff points for pediatric daytime sleepiness scale to identify excessive daytime sleepiness

The objective of the present study was to propose cutoff points for the Pediatric Daytime Sleepiness Scale (PDSS) through sensitivity and specificity analyses in order to identify excessive daytime sleepiness, considering parameters such as duration and quality of sleep, health perception, stress control and depressive moods (feelings of sadness) in adolescents. A total of 1,132 adolescents, aged 14-19 years old, of both sexes, from the public high school of São José - SC, answered the questionnaire with information on age, daytime sleepiness, sleep duration, health perception, stress management, depressive moods (feelings of sadness) and quality of sleep. The Receiver Operating Characteristic (ROC) curve was used to estimate cutoff points considering the sensitivity and specificity values ​​that best identify adolescents with excessive daytime sleepiness, using independent variables as a reference. The majority of the sample was female (54.2%), aged 14-16 years. The girls presented worse quality of sleep (66.4%), and the boys had a more positive perception of health (74.8%), better stress control (64.8%) and lower depressive moods (feelings of sadness) (63.3%). The largest area in the ROC curve was the one that considered sleep quality as a parameter in both sexes (area of the curve = 0.709 and 0.659, respectively, for boys and girls, p < 0.001). Considering sleep quality as a reference, the cutoff point for excessive daytime sleepiness was 15 points. The other parameters used were also significant (p < 0.005). Poor sleep quality was the parameter most strongly related to daytime sleepiness, and a cutoff of 15 points for the PDSS for both sexes should be used in the definition of excessive daytime sleepiness. For the other parameters, stress management, depressive mood (feelings of sadness) and health perception, different cutoff points are suggested for boys and girls.

SLEEP QUALITY AND ITS ASSOCIATION WITH PSYCHOLOGICAL SYMPTOMS IN ADOLESCENT ATHLETES

OBJECTIVE

To verify the prevalence of poor sleep quality and its association with personal characteristics and symptoms of depression, anxiety and stress in amateur adolescent athletes.

METHODS

309 adolescent athletes aged between 10 and 19 years were enrolled. Data collection included: a structured questionnaire, with personal information; the Pittsburgh Sleep Quality Index (PSQI); and the Depression, Anxiety and Stress Scale (DASS-21). Results are described in mean and standard deviation (numeric variables) and absolute and relative frequencies (categorical variables). For the inferential analysis, Student's t-test and chi-square test were performed, in addition to Poisson regression. Prevalence ratios (PR) were calculated in a 95% confidence interval (95%CI).

RESULTS

The mean age of participants was 14.1±2.1, being 13.8±2.0 and 15.0±2.1, respectively, for those with good and poor sleep quality. Poor sleep quality was recorded in 28.2% (n=87), depression in 26.9% (n=83) and anxiety/stress in 40.1% (n=124). Poor sleep quality was associated with ages between 15 and 19 years (PR 1.24; 95%CI 1.14-1.37), overweight (PR 1.12; 95%CI 1.01-1.24) and psychological symptoms of depression (PR 1.23; 95%CI 1.08-1.40) and anxiety/stress (PR 1.16; 95%CI 1.04-1.28).

CONCLUSIONS

The presence of overweight and psychological symptoms and the age over 15 years were risk factors for increasing the likelihood of poor sleep quality in adolescent athletes.