title: Trends in socioeconomic inequalities in anthropometric status in a population undergoing the nutritional transition: data from 1982, 1993 and 2004 Pelotas birth cohort studies.
abstract: BACKGROUND
  Socioeconomic inequalities in child nutrition may change rapidly over time, particularly in populations undergoing the nutrition transition. Yet, the few available studies are repeated cross-sectional surveys. By studying three prospective birth cohorts in the same city over a period of more than two decades, we describe secular trends in overweight and stunting at different ages, according to socioeconomic position.
  
  
  METHODS
  Population-based birth cohort studies were launched in the city of Pelotas (Brazil) in 1982, 1993 and 2004, with follow-up visits at twelve, 24 and 48 months. Children were weighed and measured at every visit. Z-scores of length/height-for-age and body mass index-for-age were calculated using the WHO Child Growth Standards. The slope and relative indices of inequality, based on family income quintiles, were estimated for each follow-up visit.
  
  
  RESULTS
  Between the 1982 and 2004 cohorts, stunting among four-year-olds declined (from 10.9% to 3.6%), while overweight increased (from 7.6% to 12.3%). In every visit, stunting prevalence was inversely related to income. Both absolute and relative inequalities declined over time; among four-year-olds stunting dropped from 26.0% in the 1982 cohort to 6.7% in the 2004 cohort in the poorest group, while in the richest group stunting prevalence dropped from 2.7% in 1982 to 1.1% in the 2004 cohort study. The secular trend towards increased overweight was evident for four-year-olds, in almost all socioeconomic groups, but not among one and two-year-olds. Among four-year old children, overweight prevalence increased in all income quintiles, by 130% in the middle-income group, 64% in the poorest and 41% in the richest group.
  
  
  CONCLUSIONS
  The decline in stunting is remarkable, but the increase in overweight among four-year olds - particularly among the poorest and the middle-income groups- requires concerted efforts to prevent the long term consequences of child overweight.
authors: Postgraduate Programme in Epidemiology, Federal University of Pelotas, Pelotas, RS, Brazil. amatija@yahoo.com
authors: Alicia
authors: A
authors: Matijasevich
authors: Iná S
authors: IS
authors: Santos
authors: Ana M B
authors: AM
authors: Menezes
authors: Aluísio J D
authors: AJ
authors: Barros
authors: Denise P
authors: DP
authors: Gigante
authors: Bernardo L
authors: BL
authors: Horta
authors: Fernando C
authors: FC
authors: Barros
authors: Cesar G
authors: CG
authors: Victora
mesh_terms: D000886:Anthropometry; D001827:Body Height; D015992:Body Mass Index; D001938:Brazil / Q000453:epidemiology; D015362:Child Nutrition Disorders / Q000453:epidemiology*; D002675:Child, Preschool; D002658:Developmental Disabilities / Q000453:epidemiology*; D005500:Follow-Up Studies; D054624:Health Status Disparities; D006801:Humans; D007223:Infant; D050177:Overweight / Q000453:epidemiology*; D011446:Prospective Studies; D012015:Reference Standards; D012959:Socioeconomic Factors; D014944:World Health Organization