title: Life course socioeconomic position and C-reactive protein: mediating role of health-risk behaviors and metabolic alterations. The Brazilian Longitudinal Study of Adult Health (ELSA-Brasil).
abstract: BACKGROUND
  Chronic inflammation has been postulated to be one mediating mechanism explaining the association between low socioeconomic position (SEP) and cardiovascular disease (CVD). We sought to examine the association between life course SEP and C-reactive protein (CRP) levels in adulthood, and to evaluate the extent to which health-risk behaviors and metabolic alterations mediate this association. Additionally, we explored the possible modifying influence of gender.
  
  
  RESULTS
  Our analytical sample comprised 13,371 participants from ELSA-Brasil baseline, a multicenter prospective cohort study of civil servants. SEP during childhood, young adulthood, and adulthood were considered. The potential mediators between life course SEP and CRP included clusters of health-risk behaviors (smoking, low leisure time physical activity, excessive alcohol consumption), and metabolic alterations (obesity, hypertension, low HDL, hypertriglyceridemia, and diabetes). Linear regression models were performed and structural equation modeling was used to evaluate mediation. Although lower childhood SEP was associated with higher levels of CRP in adult life, this association was not independent of adulthood SEP. However, CRP increased linearly with increasing number of unfavorable social circumstances during the life course (p trend <0.001). The metabolic alterations were the most important mediator between cumulative SEP and CRP. This mediation path accounted for 49.5% of the total effect of cumulative SEP on CRP among women, but only 20.2% among men. In consequence, the portion of the total effect of cumulative SEP on CRP that was mediated by risk behaviors and metabolic alterations was higher among women (55.4%) than among men (36.8%).
  
  
  CONCLUSIONS
  Cumulative SEP across life span was associated with elevated systemic inflammation in adulthood. Although health-risk behaviors and metabolic alterations were important mediators of this association, a sizable fraction of this association was not mediated by these factors, suggesting that other pathways might play a role, especially among men.
authors.affiliation: Postgraduate Program in Public Health, Faculty of Medicine, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil; Department of Social and Behavioral Sciences, Harvard School of Public Health, Boston, Massachusetts, United States of America.
authors.forename: Lidyane V
authors.initials: LV
authors.lastname: Camelo
authors.affiliation: Postgraduate Program in Public Health, Faculty of Medicine, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil; School of Nutrition, Universidade Federal de Ouro Preto, Ouro Preto, Minas Gerais, Brazil.
authors.forename: Luana
authors.initials: L
authors.lastname: Giatti
authors.affiliation: Faculty of Philosophy and Human Sciences, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Jorge Alexandre Barbosa
authors.initials: JA
authors.lastname: Neves
authors.affiliation: Center for Clinical and Epidemiologic Research, Hospital Universitário, Universidade de São Paulo, São Paulo, São Paulo, Brazil.
authors.forename: Paulo A
authors.initials: PA
authors.lastname: Lotufo
authors.affiliation: Center for Clinical and Epidemiologic Research, Hospital Universitário, Universidade de São Paulo, São Paulo, São Paulo, Brazil.
authors.forename: Isabela M
authors.initials: IM
authors.lastname: Benseñor
authors.affiliation: Escola Nacional de Saúde Pública, Fundação Oswaldo Cruz, Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Dóra
authors.initials: D
authors.lastname: Chor
authors.affiliation: Laboratory of Health and Environment Education, Fundação Oswaldo Cruz, Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Rosane Härter
authors.initials: RH
authors.lastname: Griep
authors.affiliation: Department of Epidemiology and Quantitative Methods in Health, Escola Nacional de Saúde Pública, Fundação Oswaldo Cruz, Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Maria de Jesus Mendes
authors.initials: Mde J
authors.lastname: da Fonseca
authors.affiliation: Department of Laboratory Medicine, Faculty of Medicine, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Pedro Guatimosim
authors.initials: PG
authors.lastname: Vidigal
authors.affiliation: Department of Social and Behavioral Sciences, Harvard School of Public Health, Boston, Massachusetts, United States of America.
authors.forename: Ichiro
authors.initials: I
authors.lastname: Kawachi
authors.affiliation: Postgraduate Studies Program in Epidemiology, School of Medicine, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil.
authors.forename: Maria Inês
authors.initials: MI
authors.lastname: Schmidt
authors.affiliation: Postgraduate Program in Public Health, Faculty of Medicine, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
authors.forename: Sandhi Maria
authors.initials: SM
authors.lastname: Barreto
mesh_terms: D000328:Adult; D000368:Aged; D001938:Brazil; D002097:C-Reactive Protein / Q000032:analysis*; D002318:Cardiovascular Diseases / Q000209:etiology*; D004522:Educational Status; D005260:Female; D015438:Health Behavior; D006304:Health Status; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D012309:Risk-Taking; D012923:Social Class; D012959:Socioeconomic Factors
chemical_list: D002097:C-Reactive Protein