title: Trends in relative weight over 1 year in low-income urban youth.
abstract: OBJECTIVE
  Recent cross-sectional data indicate the rates of childhood obesity are plateauing. Few large-scale longitudinal data sets exist, particularly in low-income and minority youth. The purpose of this study was to describe longitudinal changes in relative weight among a large sample of low-income, minority youth over 1 year.
  
  
  METHODS
  Participants were students from 56 schools in urban, low-income environments. There were 17,727 first- to sixth-graders (64% African-American, 52% male) assessed at baseline, and 13,305 youth (75.1%) were reassessed 1 year later at follow-up. Measured height and weight were used to assess categorical (overweight, obesity, severe obesity) and continuous (BMI, percentile, z-score) measures of relative weight.
  
  
  RESULTS
  Longitudinal data showed that over 1 year, BMI percentile (95% CI.64--0.32, P<0.001) and BMI z-score (95% CI: -0.02--0.01, P<0.001) were significantly lower compared to baseline. The prevalence of overweight and obesity was stable over 1 year. Most (86.0%) youth remained in the same weight category as baseline, 6.8% improved weight category, and 7.2% worsened weight category over 1 year.
  
  
  CONCLUSIONS
  These longitudinal data indicate that the relative weight of low-income, urban youth is showing signs of a small improvement over a 1-year follow-up period. The rates of childhood obesity, however, remain remarkably high and require continued, creative public health efforts.
authors.affiliation: Center for Obesity Research and Education, Temple University School of Medicine, Philadelphia, Pennsylvania, USA.
authors.forename: Hannah G
authors.initials: HG
authors.lastname: Lawman
authors.forename: Giridhar
authors.initials: G
authors.lastname: Mallya
authors.forename: Stephanie Vander
authors.initials: SV
authors.lastname: Veur
authors.forename: Tara
authors.initials: T
authors.lastname: McCoy
authors.forename: Lisa
authors.initials: L
authors.lastname: Colby
authors.forename: Tim
authors.initials: T
authors.lastname: Sanders
authors.forename: Judith
authors.initials: J
authors.lastname: Wylie-Rosett
authors.forename: Gary D
authors.initials: GD
authors.lastname: Foster
mesh_terms: D001835:Body Weight / Q000502:physiology*; D002648:Child; D003430:Cross-Sectional Studies; D005006:Ethnicity; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D009765:Obesity / Q000191:economics / Q000208:ethnology*; D015143:Philadelphia / Q000453:epidemiology; D011203:Poverty; D015995:Prevalence; D011379:Prognosis; D011795:Surveys and Questionnaires; D013997:Time Factors; D014505:Urban Population; D015430:Weight Gain