Adolescent overweight and obesity and the risk for pancreatic cancer among men and women: a nationwide study of 1.79 million Israeli adolescents

Background: There is growing concern regarding the impact of adolescent obesity on adult health. The objective of this study was to evaluate the association between body mass index (BMI) in late adolescence and the incidence of pancreatic cancer during adulthood. Methods: The authors analyzed a cohort of 1087,358 Israeli Jewish men and 707,212 Jewish women who underwent a compulsory physical examination between ages 16 and 19 years from 1967 to 2002. Pancreatic cancer incidence through December 31, 2012 was identified by linkage to the national cancer registry. Multivariable-adjusted Cox regression was used to estimate hazard ratios (HRs) for pancreatic cancer according to the US Centers for Disease Control and Prevention (CDC) BMI percentiles at baseline. Results: Over a median 23 year follow-up, 551 incident cases of pancreatic cancer cases occurred (423 men; 128 women). Compared with normal weight (5th to-<85th percentile), obesity (≥95th percentile) was associated with an increased risk of cancer among both men (HR, 3.67; 95% confidence interval [CI], 2.52-5.34) and women (HR, 4.07; 95% CI, 1.78-9.29). Among men, compared with low-normal BMI (≥5th to <25th percentile), high-normal BMI (≥75th to <85th percentile) and overweight (85th to 95th percentile) also were associated with a higher risk for cancer(high-normal BMI: HR, 1.49; 95% CI, 1.05-2.13; overweight: HR, 1.97; 95% CI, 1.39-2.80). The estimated population-attributable fraction because of overweight and obesity was 10.9% (95% CI, 6.1%-15.6%). Conclusions: Men and women who were obese or overweight as adolescents are at an increased risk for subsequent pancreatic cancer.