RESUMO
Objective: The objective is to analyze the concentration of iodine in Brazilian drinking water and its possible contribution to iodine intake for different groups. Methods: Water samples collected from primary healthcare units in eight locations distributed across all five macroregions of Brazil were analyzed. The quantification of iodine in the water samples was done by spectrophotometry (leuco crystal violet method). To classify the degree of iodine concentration, the recommendation of the Ministry of Health (China) was followed since Brazil lacks a classification standard. To verify the possible contribution of drinking water to iodine intake for different groups, the recommended water intake for each group according to the United States Institute of Medicine (2004) was considered. The percentage of iodine in drinking water and its contribution to iodine intake for different physiological groups were calculated based on the estimated average requirement (EAR) of iodine. A descriptive statistical analysis was performed using SPSS version 21.0 and Statistical Analysis Systems (SAS) version 9.2. Results: Significant differences were found between the maximum and minimum concentrations of iodine in water samples from the same location. In Pinhais (south region), the difference was 44.32 µg· L-1; in Viçosa (southeast region), it was 27.86 µg·L-1; in Rondonópolis (midwest region), it was 12.66 µg·L-1; in São Luís (northeast region), it was 11.82 µg·L-1; in Brasilian Federal District (midwest region), it was 10.98 µg·L-1; in Macaé (southeast region), it was 10.14 µg· L-1; in Palmas (north region), it was 4.22 µg·L-1; and in Vitória (southeast region), it was 1.69 µg·L-1. The maximum concentrations of iodine found in the drinking water of Pinhais and Viçosa can contribute more than 70.0% and 50.0%, respectively, to daily iodine intake for all groups. Conclusion: Monitoring the concentration of iodine in drinking water from different locations in each city or Federal District is a preventive measure against inadequate iodine intake and possible adverse changes in population health.
RESUMO
PURPOSE: The aim of the study was to evaluate the reliability of 7 anthropometric indices in predicting cardiovascular risk markers (CRMs) and metabolic syndrome (MetS) in Brazilian adolescents. METHODS: A cross-sectional study conducted with 1,069 participants of the Cardiovascular Risk in Adolescents Study aged 12-17 years. Receiver operating characteristics curves were plotted, and area under curve (AUC) was calculated for body mass index (BMI), waist circumference (WC), waist-to-height ratio (WHR), conicity index (CoI), body shape index (BSI), adjusted BSI for adolescents (adjusted BSI), and body roundness index (BRI). RESULTS: In girls, reliability of BMI, WC, WHR, and BRI was sufficient (≥.6 AUC <.7) only to predict high blood pressure. Among boys, reliability of BMI, WC, WHR, BRI, and adjusted BSI ranged from good to sufficient (≥6 AUC <.8) to predict insulin resistance and high blood pressure, but poor to sufficient (≥.5 AUC <.7) for high total cholesterol, triglycerides, and low-density lipoprotein. For both sexes, CoI and BSI presented AUC ≤.5 for all CRM. A majority of the anthropometric indices showed AUC ≥.9 for MetS. CONCLUSION: Reliability of CoI, BSI, adjusted BSI, and BRI is not superior to BMI, WC, and WHR in predicting CRM and MetS. All the anthropometric indices had excellent predictive capacity for MetS, but limited accuracy for CRM. Among the evaluated indices, we recommend the use of cutoff point WHR ≥.55 to screening MetS in girls and boys because of its easy to measure and interpretation.
