Association of parental level of education and child factors on length-for-age indicator among socially vulnerable children aged 6-24 months from a Brazilian state using structural equation modelling.

This cross-sectional study employs structural equation modelling (sEM) to explore both direct and indirect effects of parental level of education and child individual factors on the length-for-age outcomes in children aged 6-24 months assisted by the Bolsa Família Program in the State of Alagoas. A total of 1448 children were analysed by the sEM technique. A negative standardised direct effect (sDE) of the children's younger age (sDE: -0·06; P = 0·017), the use of bottle feeding (sDE: -0·11; P < 0·001) and lack of a minimum acceptable diet (sDE: -0·09; P < 0·001) on the length-for-age indicator was found. Being female (SDE: 0·08; P = 0·001), a higher birth weight (SDE: 0·33; P < 0·001), being ever breastfed (sdE: 0·07; P = 0·004) and a higher level of parental education (SDE: 0·09; P < 0·001) showed a positive SDE effect on the child's length-for-age. The model also demonstrated a negative standardised indirect effect (SIE) of the sweet beverage consumption (SIE: -0·08; P = 0·003) and a positive effect of being ever breastfed (SIE: 0·06; P = 0·017) on the child's length-for-age through parental level of education as a mediator. This research underscores the crucial role of proper feeding practices and provides valuable insights for the development of targeted interventions, policies and programmes to improve nutritional well-being and promote adequate linear growth and development among young children facing similar challenges.

Beyond sleep duration: Sleep timing is associated with BMI among Brazilian adults.

Objectives: To examine the association of sleep duration and timing with BMI among adults. Also, to identify obesogenic and unhealthy behaviors (e.g.diet/sleep quality, physical activity, screen time, smoking) associated with short sleep duration and late bedtime. Participants: Participants (n=755) were part of exploratory, population-based research, with data collection in a virtual environment. Methods: For purposes of characterizing the population we considered short sleepers<7h/night, and the population bedtime median was used to stratify participants into early and late sleepers (before and after 23:08). Student's t-test and chi-square test were performed to assess differences in characteristics between groups. Linear regression analyses were conducted to determine the association of sleep duration, bedtime, and wake-up time with BMI. Quantile regression was estimated for the 25th, 50th, and 75th quantiles to identify the distributional correlations between BMI and sleep variables. Restricted cubic splines were also used to study the shape of the association between sleep-BMI. Analyses were adjusted for potential confounding variables. Results: BMI decreased by 0.40Kg/m2 for each additional hour of sleep duration [95%CI=-0.68,-0.12,p=0.005] and increased by 0.37 kg/m2 for each additional hour of bedtime [95%CI=0.12,0.61,p=0.003]. The association between bedtime and BMI remained even after adjustment for sleep duration. These effects were higher and stronger with higher BMI values (p75th). Wake-up time did not show statistically significant associations. Conclusions: Because we found that beyond sleep duration, bedtime was significantly associated with BMI, our data reflect the pertinence of assessing sleep timing patterns in disentangling sleep-obesity association. Insights into the characteristics, obesogenic and unhealthy behaviors related to short and late sleep may support specific strategies to prevent and treat excess body adiposity and other negative health outcomes.

Sleep and circadian hygiene practices association with sleep quality among Brazilian adults.

Objective: To investigate the association of sleep and circadian hygiene practices (sleep-promoting and sleep-disturbing behaviors) with sleep quality indicators. Methods: Participants (n = 2050; 18-65 y) were part of virtual population-based research. Logistic regression models were fitted to assess differences in the OR (95% CI) of poor quality with sleep-promoting/disturbing practices (time-of-day of exercise, pre-bedtime routine, naps, electronic devices with illuminated screens, caffeine and alcohol consumption, and smoking). Linear regression analyses evaluated differences in sleep duration, latency, and awakenings associated with the same variables. Restricted cubic splines were used to study the shape of the association of screen time before bed with sleep duration, latency, and awakenings. Analyses were adjusted for age, sex, region, marital status, educational level, evening diet quality, and BMI. Results: Evening use of electronic devices with illuminated screens showed a negative effect on all sleep parameters. Reporting dinner as the largest meal and evening caffeine consumption was associated with shorter sleep duration and longer sleep latency. Smokers had higher odds of longer latency. A protective effect of morning exercises was demonstrated on sleep quality, latency, and awakenings. Alcohol consumers presented lower odds of poor quality and lower frequency of awakenings. Pre-bedtime practices showed no or negative effect on sleep outcomes. Conclusions: Recommendations to promote sleep quality and prevent sleep-related problems, with corresponding circadian health benefits, should include engaging in regular exercise, preferably in the morning, and avoiding naps, heavy meals close to bedtime, caffeine, smoking, and evening screen exposure.