title: Weight History and All-Cause and Cause-Specific Mortality in Three Prospective Cohort Studies.
abstract: BACKGROUND
  The relationship between body mass index (BMI) and mortality is controversial.
  
  
  OBJECTIVE
  To investigate the relationship between maximum BMI over 16 years and subsequent mortality.
  
  
  METHODS
  3 prospective cohort studies.
  
  
  METHODS
  Nurses' Health Study I and II and Health Professionals Follow-Up Study.
  
  
  METHODS
  225 072 men and women with 32 571 deaths observed over a mean of 12.3 years of follow-up.
  
  
  METHODS
  Maximum BMI over 16 years of weight history and all-cause and cause-specific mortality.
  
  
  RESULTS
  Maximum BMIs in the overweight (25.0 to 29.9 kg/m2) (multivariate hazard ratio [HR], 1.06 [95% CI, 1.03 to 1.08]), obese I (30.0 to 34.9 kg/m2) (HR, 1.24 [CI, 1.20 to 1.29]), and obese II (≥35.0 kg/m2) (HR, 1.73 [CI, 1.66 to 1.80]) categories were associated with increases in risk for all-cause death. The pattern of excess risk with a maximum BMI above normal weight was maintained across strata defined by smoking status, sex, and age, but the excess was greatest among those younger than 70 years and never-smokers. In contrast, a significant inverse association between overweight and mortality (HR, 0.96 [CI, 0.94 to 0.99]) was observed when BMI was defined using a single baseline measurement. Maximum overweight was also associated with increased cause-specific mortality, including death from cardiovascular disease and coronary heart disease.
  
  
  CONCLUSIONS
  Residual confounding and misclassification.
  
  
  CONCLUSIONS
  The paradoxical association between overweight and mortality is reversed in analyses incorporating weight history. Maximum BMI may be a useful metric to minimize reverse causation bias associated with a single baseline BMI assessment.
  
  
  BACKGROUND
  National Institutes of Health.
authors.affiliation: From Harvard T.H. Chan School of Public Health, Brigham and Women's Hospital, Harvard Medical School, and Boston University School of Public Health, Boston, Massachusetts.
authors.forename: Edward
authors.initials: E
authors.lastname: Yu
authors.affiliation: From Harvard T.H. Chan School of Public Health, Brigham and Women's Hospital, Harvard Medical School, and Boston University School of Public Health, Boston, Massachusetts.
authors.forename: Sylvia H
authors.initials: SH
authors.lastname: Ley
authors.affiliation: From Harvard T.H. Chan School of Public Health, Brigham and Women's Hospital, Harvard Medical School, and Boston University School of Public Health, Boston, Massachusetts.
authors.forename: JoAnn E
authors.initials: JE
authors.lastname: Manson
authors.affiliation: From Harvard T.H. Chan School of Public Health, Brigham and Women's Hospital, Harvard Medical School, and Boston University School of Public Health, Boston, Massachusetts.
authors.forename: Walter
authors.initials: W
authors.lastname: Willett
authors.affiliation: From Harvard T.H. Chan School of Public Health, Brigham and Women's Hospital, Harvard Medical School, and Boston University School of Public Health, Boston, Massachusetts.
authors.forename: Ambika
authors.initials: A
authors.lastname: Satija
authors.affiliation: From Harvard T.H. Chan School of Public Health, Brigham and Women's Hospital, Harvard Medical School, and Boston University School of Public Health, Boston, Massachusetts.
authors.forename: Frank B
authors.initials: FB
authors.lastname: Hu
authors.affiliation: From Harvard T.H. Chan School of Public Health, Brigham and Women's Hospital, Harvard Medical School, and Boston University School of Public Health, Boston, Massachusetts.
authors.forename: Andrew
authors.initials: A
authors.lastname: Stokes
mesh_terms: D000328:Adult; D000368:Aged; D015992:Body Mass Index; D002423:Cause of Death; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000401:mortality; D050177:Overweight / Q000401:mortality; D011446:Prospective Studies