The Brazilian consensus for the clinical approach and treatment of subclinical hypothyroidism in adults: recommendations of the thyroid Department of the Brazilian Society of Endocrinology and Metabolism

Introduction: Subclinical hypothyroidism (SCH), defined as elevated concentrations of thyroid stimulating hormone (TSH) despite normal levels of thyroid hormones, is highly prevalent in Brazil, especially among women and the elderly. Although an increasing number of studies have related SCH to an increased risk of coronary artery disease and mortality, there have been no randomized clinical trials verifying the benefit of levothyroxine treatment in reducing these risks, and the treatment remains controversial. Objective: This consensus, sponsored by the Thyroid Department of the Brazilian Society of Endocrinology and Metabolism and developed by Brazilian experts with extensive clinical experience with thyroid diseases, presents these recommendations based on evidence for the clinical management of SCH patients in Brazil. Materials and methods: After structuring the clinical questions, the search for evidence in the literature was initially performed in the MedLine-PubMed database and later in the Embase and SciELO - Lilacs databases. The strength of evidence was evaluated according to the Oxford classification system and established based on the experimental design used, considering the best available evidence for each question and the Brazilian experience. Results: The topics covered included SCH definition and diagnosis, natural history, clinical significance, treatment and pregnancy, and the consensus issued 29 recommendations for the clinical management of adult patients with SCH. Conclusion: Treatment with levothyroxine was recommended for all patients with persistent SCH with serum TSH values >= 10 mU/L and for certain patient subgroups.