title: Duration and Degree of Weight Gain and Incident Diabetes in Younger Versus Middle-Aged Black and White Adults: ARIC, CARDIA, and the Framingham Heart Study.
abstract: OBJECTIVE
  To determine whether duration and degree of weight gain are differentially associated with diabetes risk in younger versus middle-aged black and white adults.
  
  
  METHODS
  We combined data from three cohort studies: Atherosclerosis Risk in Communities (ARIC), Coronary Artery Risk Development in Young Adults (CARDIA), and the Framingham Heart Study. A total of 17,404 participants (56% women; 21% black) were stratified by baseline age (younger: ≥30 and <45 years; middle-aged: ≥45 and <60 years) and examined for incident diabetes (median follow-up 9 years). Duration and degree of gain in BMI were calculated as "BMI-years" above one's baseline BMI.
  
  
  RESULTS
  Diabetes incidence per 1,000 person-years in the younger and middle-aged groups was 7.2 (95% CI 5.7, 8.7) and 24.4 (22.0, 26.8) in blacks, respectively, and 3.4 (2.8, 4.0) and 10.5 (9.9, 11.2) in whites, respectively. After adjusting for sex, baseline BMI and other cardiometabolic factors, and age and race interaction terms, gains in BMI-years were associated with higher risk of diabetes in the younger compared with middle-aged groups: hazard ratios for 1-unit increase in log BMI-years in younger versus middle-aged blacks were 1.18 (P = 0.02) and 1.02 (P = 0.39), respectively (P for interaction by age-group = 0.047), and in whites were 1.35 (P < 0.001) and 1.11 (P < 0.001), respectively (P for interaction by age-group = 0.008).
  
  
  CONCLUSIONS
  Although middle-aged adults have higher rates of diabetes, younger adults are at greater relative risk of developing diabetes for a given level of duration and degree of weight gain.
authors.affiliation: Division of Cardiovascular Sciences, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD weig@nhlbi.nih.gov.
authors.forename: Gina S
authors.initials: GS
authors.lastname: Wei
authors.affiliation: Division of Cardiovascular Sciences, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD.
authors.forename: Sean A
authors.initials: SA
authors.lastname: Coady
authors.affiliation: Division of Cardiovascular Sciences, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD.
authors.forename: Jared P
authors.initials: JP
authors.lastname: Reis
authors.affiliation: Department of Preventive Medicine, Feinberg School of Medicine, Northwestern University, Chicago, IL.
authors.forename: Mercedes R
authors.initials: MR
authors.lastname: Carnethon
authors.affiliation: Department of Epidemiology and the Welch Center for Prevention, Epidemiology and Clinical Research, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD Division of General Internal Medicine, Department of Medicine, Johns Hopkins University, Baltimore, MD.
authors.forename: Josef
authors.initials: J
authors.lastname: Coresh
authors.affiliation: Department of Mathematics and Statistics, Boston University, Boston, MA.
authors.forename: Ralph B
authors.initials: RB
authors.lastname: D'Agostino
authors.affiliation: Office of the Dean, Colorado School of Public Health, Aurora, CO.
authors.forename: David C
authors.initials: DC
authors.lastname: Goff
authors.affiliation: Division of Epidemiology and Community Health, School of Public Health, University of Minnesota, Minneapolis, MN.
authors.forename: David R
authors.initials: DR
authors.lastname: Jacobs
authors.affiliation: Department of Epidemiology and the Welch Center for Prevention, Epidemiology and Clinical Research, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD Division of General Internal Medicine, Department of Medicine, Johns Hopkins University, Baltimore, MD.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Selvin
authors.affiliation: Framingham Heart Study, Center for Population Studies, National Heart, Lung, and Blood Institute, Bethesda, MD.
authors.forename: Caroline S
authors.initials: CS
authors.lastname: Fox
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D044383:Black People / Q000706:statistics & numerical data*; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D003924:Diabetes Mellitus, Type 2 / Q000453:epidemiology* / Q000208:ethnology; D005260:Female; D006801:Humans; D015994:Incidence; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D012720:Severity of Illness Index; D013997:Time Factors; D014481:United States / Q000453:epidemiology; D015430:Weight Gain / Q000502:physiology*; D044465:White People / Q000706:statistics & numerical data*; D055815:Young Adult; D001741:Black or African American