title: Long-term status and change of body fat distribution, and risk of colorectal cancer: a prospective cohort study.
abstract: Although obesity has been linked to an increased risk of colorectal cancer (CRC), the risk associated with long-term status or change of body fat distribution has not been fully elucidated.
  
  
  
  Using repeated anthropometric assessments in the Nurses' Health Study and Health Professionals Follow-up Study, we prospectively investigated cumulative average waist circumference, hip circumference and waist-to-hip ratio, as well as their 10-year changes over adulthood, in relation to CRC risk over 23-24 years of follow-up. Cox proportional hazards models were used to calculate the hazard ratio (HR) and 95% confidence interval (CI).
  
  
  
  High waist circumference, hip circumference and waist-to-hip ratio were all associated with a higher CRC risk in men, even after adjusting for body mass index. The association was attenuated to null in women after adjusting for body mass index. Ten-year gain of waist circumference was positively associated with CRC risk in men (P for trend = 0.03), but not in women (P for trend = 0.34).Compared with men maintaining their waist circumference, those gaining waist circumference by ≥ 10 cm were at a higher risk of CRC, with a multivariable-adjusted HR of 1.59 (95% CI, 1.01-2.49). This association appeared to be independent of weight change.
  
  
  
  Abdominal adiposity, independent of overall obesity, is associated with an increased CRC risk in men but not in women. Our findings also provide the first prospective evidence that waist circumference gain during adulthood may be associated with higher CRC risk in men, thus highlighting the importance of maintaining a healthy waist for CRC prevention.
authors.affiliation: Department of Nutrition, Department of Epidemiology, Harvard T.H. ChanSchool of Public Health, Boston, MA, USA, msong@hsph.harvard.edu.
authors.forename: Mingyang
authors.initials: M
authors.lastname: Song
authors.affiliation: Department of Nutrition, Department of Epidemiology, Harvard T.H. ChanSchool of Public Health, Boston, MA, USA, Channing Division of Network Medicine, Harvard Medical School, Boston, MA, USA.
authors.forename: Frank B
authors.initials: FB
authors.lastname: Hu
authors.affiliation: Department of Nutrition, Department of Epidemiology, Harvard T.H. ChanSchool of Public Health, Boston, MA, USA, Department of Biostatistics, Department of Global Health and Population, Harvard T.H. ChanSchool of Public Health, Boston, MA, USA.
authors.forename: Donna
authors.initials: D
authors.lastname: Spiegelman
authors.affiliation: Channing Division of Network Medicine, Harvard Medical School, Boston, MA, USA, Division of Gastroenterology, Massachusetts General Hospital, Boston, MA, USA.
authors.forename: Andrew T
authors.initials: AT
authors.lastname: Chan
authors.affiliation: Department of Nutrition.
authors.forename: Kana
authors.initials: K
authors.lastname: Wu
authors.affiliation: Department of Epidemiology, Harvard T.H. ChanSchool of Public Health, Boston, MA, USA, Channing Division of Network Medicine, Harvard Medical School, Boston, MA, USA, Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA and Department of Pathology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA, USA.
authors.forename: Shuji
authors.initials: S
authors.lastname: Ogino
authors.affiliation: Channing Division of Network Medicine, Harvard Medical School, Boston, MA, USA, Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA and.
authors.forename: Charles S
authors.initials: CS
authors.lastname: Fuchs
authors.affiliation: Department of Nutrition, Department of Epidemiology, Harvard T.H. ChanSchool of Public Health, Boston, MA, USA, Channing Division of Network Medicine, Harvard Medical School, Boston, MA, USA.
authors.forename: Walter C
authors.initials: WC
authors.lastname: Willett
authors.affiliation: Department of Nutrition, Department of Epidemiology, Harvard T.H. ChanSchool of Public Health, Boston, MA, USA, Channing Division of Network Medicine, Harvard Medical School, Boston, MA, USA.
authors.forename: Edward L
authors.initials: EL
authors.lastname: Giovannucci
mesh_terms: D000328:Adult; D000368:Aged; D050218:Body Fat Distribution; D015992:Body Mass Index; D015179:Colorectal Neoplasms / Q000453:epidemiology*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D056128:Obesity, Abdominal / Q000150:complications; D016016:Proportional Hazards Models; D011446:Prospective Studies; D012307:Risk Factors; D012727:Sex Characteristics; D014481:United States / Q000453:epidemiology; D055105:Waist Circumference; D049629:Waist-Hip Ratio
keywords: Body fat distribution; postmenopausal hormone therapy; sex difference