Sleep Duration in Adolescence and Its Prenatal, Perinatal, and Health Determinants in a Large Population-based Cohort Followed from Birth.

Objective To investigate sleep duration and its associated factors in adolescents aged 11 years from the 2004 Pelotas (Brazil) Birth Cohort Study. Methods Sleep duration was assessed using a self-report sleep habits. Independent variables included perinatal, sociodemographic, behavioral, and health characteristics. The associations were estimated using multiple linear regression. Results The mean sleep duration of 3,179 adolescents was 9.3 hour (SD =1.7 hour). Longer sleep duration was associated with lower socioeconomic status at birth (ß: 0.37, 95% CI: 0.12; 0.61), lower mother's education level ( p < 0.001), and being female (ß: 0.19, 95% CI: 0.06; 0.33). Shorter sleep duration was associated with cesarean section delivery (ß: -0.16, 95% CI: -0.31; -0.02); having classes in the morning shift (ß: -1.38, 95% CI: -1.51; -1.26), and lower terciles of physical activity ( p = 0.04). Conclusions The mean sleep duration observed in this study was consistent with the international recommendations for this age range. Adolescents from lower income families, who are more active, study in shifts other than morning, girls, and those born through vaginal delivery presented higher sleep duration than their counterparts.

Socioeconomic inequalities explain the association between source of drinking water and dental caries in primary dentition.

OBJECTIVE: To evaluate the association between source of drinking water and dental caries at age 5 and to test whether socioeconomic conditions act as confounding factors in such association. METHODS: The study was carried out in a sub-sample of the 2004 Pelotas Birth Cohort, which comprised the application of a questionnaire and clinical oral examination. The exposure was source of drinking water, collected through a question to the primary caregiver. The outcome was dental caries in primary dentition, measured through several standardized indicators of the decayed, missing and filled teeth index (dmft), assessing past and present dental caries. Socioeconomic indicators (family income and maternal education) were identified as potential confounding factors. After descriptive analysis, the association between source of water and measures of dental caries was assessed by Regression models. RESULTS: 1,084 children were evaluated and had complete information in all variables (83.2 % of the targeted sample). Dental caries experience was observed in 48.7 % of the children, with a mean of 1.9 decayed, missing or filled teeth. Most children consumed water from public water supply (76.0 %), and a socioeconomic pattern was observed, with children from lower income more likely to drink water from public supply. In crude analysis, children who consumed bottled water had a lower risk of decayed teeth, lower experience of dental caries and less severe disease. No associations were observed after adjustments for socioeconomic conditions. CONCLUSION: Underlying socioeconomic inequalities explained the association between prevalence and severity of dental caries in primary dentition and source of drinking water. CLINICAL SIGNIFICANCE: Drinking fluoridated tap water is as effective in dental caries prevention as bottled water with acceptable levels of fluoride, with the advantage of being accessible to all. Oral health prevention and treatment should be implemented as early in life as possible and should take into consideration the family's socioeconomic context.

Iodine Status of Brazilian School-Age Children: A National Cross-Sectional Survey.

Salt iodization is the main public health policy to prevent and control iodine deficiency disorders. The National Salt Iodization Impact Assessment Survey (PNAISAL) was conducted to measure iodine concentration among Brazilian schoolchildren. A survey including 6-14-year-old schoolchildren from public and private schools from all 26 Brazilian states and the Federal District was carried out in the biennia 2008-2009 and 2013-2014. Municipalities, schools, and students were randomly selected. Students were interviewed at school using a standard questionnaire, which included the collection of demographic, educational, weight, height, and 10 mL non-fasting urine collection information. The analyses were weighted according to the population of students per federative unit. The median urinary iodine concentration (MUIC) for the entire sample by region, federative unit per school, and student characteristics, was described from the cutoff points defined by the World Health Organization (severe disability: <20 µg/L, moderate: 20-49 µg/L, mild: 50-99 µg/L, adequate: 100-199 µg/L, more than adequate: 200-299 µg/L, and excessive: >300 µg/L). In total, 18,864 students (95.9% of the total) from 818 schools in 477 municipalities from all federative units were included in this study. Almost 70% were brown skin color, nine-years-old or older, studied in urban schools, and were enrolled in elementary school. The prevalence of overweight/obesity, as measured by body mass index (BMI) for age, was about twice as high compared to nutritional deficits (17.3% versus 9.6%). The MUIC arrived at 276.7 µg/L (25th percentile = 175.5 µg/L and 75th percentile = 399.71 µg/L). In Brazil as a whole, the prevalence of mild, moderate, and severe deficit was 6.9%, 2.6%, and 0.6%, respectively. About one-fifth of the students (20.7%) had adequate iodine concentration, while 24.9% and 44.2% had more than adequate or excessive concentration, respectively. The prevalence of iodine deficits was significantly higher among younger female students from municipal public schools living in rural areas with the lowest BMI. The median urine iodine concentration showed that Brazilian students have an adequate nutritional intake, with a significant proportion of them evidencing overconsumption of this micronutrient.