title: Measured body mass index in adolescence and the incidence of colorectal cancer in a cohort of 1.1 million males.
abstract: The increasing prevalence of adolescent obesity affects adult health. We investigated the association of adolescent overweight with colorectal cancer incidence in a large cohort of males.
  
  
  
  Body mass index (BMI) was measured in 1.1 million Jewish Israeli males who underwent a general health examination at ages 16 to 19 between 1967 and 2005. Overweight was defined as BMI ≥ 85th percentile of the standard U.S. distribution in adolescence. Colorectal cancer was identified by linkage with the Israel National Cancer Registry up to 2006. The mean follow-up period was 17.6 ± 10.9 years, reflecting 19.5 million person-years. Cox proportional hazards modeling was used.
  
  
  
  The prevalence of adolescent overweight increased from 9.9% to 16.8% in the first 10 and last 10 annual examination cohorts. Colon (n = 445) and rectal cancer (n = 193) cases were detected. Overweight predicted an increased risk of colon cancer [HR = 1.53; 95% confidence interval (CI), 1.17-2.02, P = 0.002] but not of rectal cancer (HR = 1.09; 95% CI, 0.38-1.73, P = 0.72). The risk was greatest for nonmucinous adenocarcinoma of the colon (HR = 1.68, 95% CI, 1.26-2.23, P = 0.001). The association of BMI ≥ 85th percentile with colon cancer was even more pronounced in analyses that were restricted to men followed until at least 40 years of age [N = 367,478; HR = 1.75 (95% CI, 1.33-2.3, P < 0.001)].
  
  
  
  Adolescent overweight is substantially associated with colon cancer incidence in young to middle-aged adults.
  
  
  
  These long-term sequelae add to the urgency to seriously address increasing childhood and adolescent obesity with its attendant increasing population impact.
authors: Medical Corps, Israeli Defense Force, Israel. Zohar_levi@012.net.il
authors: Zohar
authors: Z
authors: Levi
authors: Jeremy D
authors: JD
authors: Kark
authors: Micha
authors: M
authors: Barchana
authors: Irena
authors: I
authors: Liphshitz
authors: Ofir
authors: O
authors: Zavdy
authors: Dorit
authors: D
authors: Tzur
authors: Estela
authors: E
authors: Derazne
authors: Moshe
authors: M
authors: Furman
authors: Yaron
authors: Y
authors: Niv
authors: Barak
authors: B
authors: Gordon
authors: Arnon
authors: A
authors: Afek
authors: Ari
authors: A
authors: Shamiss
mesh_terms: D000293:Adolescent; D000328:Adult; D015992:Body Mass Index; D015331:Cohort Studies; D015179:Colorectal Neoplasms / Q000453:epidemiology*; D006801:Humans; D015994:Incidence; D007557:Israel / Q000453:epidemiology; D008297:Male; D009765:Obesity / Q000453:epidemiology*; D050177:Overweight / Q000453:epidemiology*; D055815:Young Adult