title: Thyrotropin levels are associated with chronic kidney disease among healthy subjects in cross-sectional analysis of the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil).
abstract: BACKGROUND
  Few studies have evaluated a possible relationship between thyrotropin levels and glomerular filtration rate (GFR) and albumin/creatinine ratio in euthyroid subjects. We aimed to analyze this association using baseline data from the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil).
  
  
  METHODS
  Cross-sectionally, we included subjects with normal thyroid function and with subclinical hypothyroidism (SCH). We excluded individuals using medications that affect thyroid function. Linear and logistic regression models evaluated GFR estimated by Chronic Kidney Disease Epidemiology Collaboration (CKD-Epi) and albuminuria/creatinine ratio as dependent variables and thyrotropin quartiles in individuals with euthyroidism and SCH as independent variables, adjusted for demographical characteristics and diseases related to CKD.
  
  
  RESULTS
  We included 13,193 subjects with a median age of 51 years [interquartile range, (IQR): 45-58], 6840 (51.8%) women, 12,416 (94.1%) euthyroid, and 777 (5.9%) with SCH. SCH subjects were characterized by higher age, triglycerides, frequency of white race, cardiovascular disease, CKD, and former smokers. In adjusted models, log-transformed TSH in euthyroid subjects was inversely and strongly associated with CKD (β = -2.181, 95% CI -2.714 to -1.648), P < 0.0001 for glomerular filtration rate and 4.528 (1.190-7.865) for albuminuria/creatinine ratio. Multivariate logistic models for euthyroid subjects showed an OR of 1.45 (95% CI 1.15-1.83) for GFR and of 1.95 (95% CI 1.08-3.54) for albuminuria/creatinine ratio in the fourth quartile of TSH using the first as the reference.
  
  
  CONCLUSIONS
  Thyrotropin levels are independently associated with CKD in euthyroid subjects.
authors.affiliation: Centro de Pesquisa Clínica, Hospital Universitário, Universidade de São Paulo, Av. Lineu Prestes 2565, 3rd floor, São Paulo, SP, CEP 05508-000, Brazil.
authors.forename: Érique José F
authors.initials: ÉJF
authors.lastname: Peixoto de Miranda
authors.affiliation: Centro de Pesquisa Clínica, Hospital Universitário, Universidade de São Paulo, Av. Lineu Prestes 2565, 3rd floor, São Paulo, SP, CEP 05508-000, Brazil.
authors.forename: Márcio Sommer
authors.initials: MS
authors.lastname: Bittencourt
authors.affiliation: Centro de Pesquisa Clínica, Hospital Universitário, Universidade de São Paulo, Av. Lineu Prestes 2565, 3rd floor, São Paulo, SP, CEP 05508-000, Brazil.
authors.forename: Alessandra C
authors.initials: AC
authors.lastname: Goulart
authors.affiliation: Centro de Pesquisa Clínica, Hospital Universitário, Universidade de São Paulo, Av. Lineu Prestes 2565, 3rd floor, São Paulo, SP, CEP 05508-000, Brazil.
authors.forename: Itamar S
authors.initials: IS
authors.lastname: Santos
authors.affiliation: Divisão de Nefrologia do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo, Av. Dr. Enéas de Carvalho Aguiar, 255, Cerqueira César, São Paulo, CEP: 05403-000, Brazil.
authors.forename: Silvia Maria
authors.initials: SM
authors.lastname: de Oliveira Titan
authors.affiliation: Secretaria Municipal de Saúde de Belo Horizonte, Avenida Afonso Pena, 2336, Funcionários, Belo Horizonte, CEP 30130-007, Brazil.|Faculdade de Medicina, Universidade Federal de Minas Gerais, Av. Alfredo Balena, 190, Belo Horizonte, CEP 30320050, Brazil.
authors.forename: Roberto Marini
authors.initials: RM
authors.lastname: Ladeira
authors.affiliation: Faculdade de Medicina, Universidade Federal de Minas Gerais, Av. Alfredo Balena, 190, Belo Horizonte, CEP 30320050, Brazil.
authors.forename: Sandhi Maria
authors.initials: SM
authors.lastname: Barreto
authors.affiliation: Centro de Pesquisa Clínica, Hospital Universitário, Universidade de São Paulo, Av. Lineu Prestes 2565, 3rd floor, São Paulo, SP, CEP 05508-000, Brazil.
authors.forename: Paulo A
authors.initials: PA
authors.lastname: Lotufo
authors.affiliation: Centro de Pesquisa Clínica, Hospital Universitário, Universidade de São Paulo, Av. Lineu Prestes 2565, 3rd floor, São Paulo, SP, CEP 05508-000, Brazil. isabensenor@gmail.com.
authors.forename: Isabela Judith Martins
authors.initials: IJM
authors.lastname: Benseñor
mesh_terms: D015331:Cohort Studies; D003430:Cross-Sectional Studies; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007037:Hypothyroidism / Q000097:blood*; D008297:Male; D008875:Middle Aged; D051436:Renal Insufficiency, Chronic / Q000097:blood*; D013972:Thyrotropin / Q000097:blood*
chemical_list: D013972:Thyrotropin
keywords: CKD-Epi; Chronic kidney disease; Glomerular filtration rate; Subclinical hypothyroidism; Thyroid dysfunction