ABSTRACT Objective: Although some previous data have suggested a high iodine intake in Brazil, the prevalence of antithyroperoxidase antibodies (TPOAb) in the country is compatible with rates from countries with adequate iodine intake. This observation emphasizes the importance of knowing the incidence of TPOAb in Brazil. Materials and methods: This prospective analysis included euthyroid participants with negative TPOAb at baseline and a thyroid function assessment at a 4-year follow-up. TPOAb was measured by electrochemiluminescence and considered positive when titers were ≥34 IU/mL. TSH and free T4 (FT4) levels were determined by a third-generation immunoenzymatic assay. The incidence of TPOAb is expressed in percentage per year or as a cumulative incidence within the 4-year follow-up period. Results: Of 8,922 euthyroid participants (mean age 51.1 years; 50.9% women) with a negative TPOAb test at baseline, 130 presented incident TPOAb at the 4-year follow-up, yielding an annual incidence of TPOAb of 0.38%/year (95% confidence interval [95% CI], 0.37-0.39%/year) and a cumulative incidence over 4 years of 1.46% (95% CI, 1.21-1.71%). In men, the annual incidence was 0.32% (95% CI, 0.31-0.33%), and the cumulative incidence over 4 years was 1.23% (95% CI, 0.90-1.56%). In women, the annual incidence was 0.43%/year (95% CI, 0.42-0.44%/year) and the cumulative incidence over 4 years was 1.67% (95% CI, 1.30-2.04%). The only factor associated with incident TPOAb was the occurrence of thyroid diseases at follow-up. No differences in TPOAb incidence were detected across ELSA-Brasil research centers. Conclusion: Based on the results of this study, the incidence of TPOAb per year and at a 4-year follow-up period are compatible with those of a country with adequate iodine intake.

ABSTRACT Objective: To evaluate incidence of subclinical and overt hyperthyroidism and hypothyroidism. Subjects and methods: The Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) is a prospective cohort study of 15,105 civil servants, examined at baseline and over a 4-year follow-up. This analysis included 9,705 participants with normal thyroid function at baseline, follow-up information about thyroid function and with no report of using drugs that may interfere in the thyroid function. Thyroid function was defined by TSH/FT4 levels or routine use of thyroid hormones/anti-thyroid medications. Annual and cumulative (over 4-year) incidence rates were presented as percentages (95% Confidence Intervals). Results: The incidence of all overt and subclinical thyroid disease was 6.7% (1.73%/year): 0.19% for overt hyperthyroidism (0.048%/year), 0.54% for subclinical hyperthyroidism (0.14%/year), 1.98% for overt hypothyroidism (0.51%/year), and 3.99% for subclinical hypothyroidism (1.03%/year). The incidence of all thyroid diseases was higher in women, when compared to men, with a low women:men ratio (1.36). For Blacks the highest incidence was for overt hyperthyroidism, while for Whites, the highest incidence was for overt hypothyroidism. However, the highest incidence of overt hyperthyroidism was detected in Asian descendants. The presence of antithyroperoxidase antibodies at baseline was associated with higher incidence of overt thyroid diseases. Conclusion: These results showed a high incidence of hypothyroidism, which is compatible with a country with a more-than-adequate iodine intake. The low women:men ratio of the incidence of thyroid dysfunction highlights the importance of the diagnosis of thyroid diseases among men in Brazil.

ABSTRACT This study aimed to monitor degradation of compost from undigested sewage sludge disposed on soil surface or incorporated it. The sewage sludge was blended with wood sawdust during a 90-day composting to achieve a C/N ratio of 9. Each waste was dosed based on its total content of nitrogen and on an annual dose of 500 kg ha-1, which is broadly recommended for forage fertilization. After incorporation and surface applied (five replicates each), waste mineralization was monitored for 131 days by samplings taken from both conditions for further analyses. The samples were measured for total organic carbon (TOC); easily oxidizable carbon (OOC); total nitrogen (TN); ammonia and nitric nitrogen, and from them the total organic nitrogen (ON); volatile solids; and water content. The findings pointed to a decrease in TOC, OOC and ON contents throughout monitoring, regardless of disposal method, however, most remarkable whether incorporated to the soil, computing mineralization rates above 87%.