Overall obesity, abdominal adiposity, diabetes and cigarette smoking in relation to the risk of pancreatic cancer in two Swedish population-based cohorts

Abstract

We examined the associations of body mass index (BMI), waist circumference, a history of diabetes, and cigarette smoking with risk of pancreatic cancer among 37,147 women and 45,906 men followed up during 560,666 person-years in the Swedish Mammography Cohort and the Cohort of Swedish Men; 136 incident cases of pancreatic cancer were diagnosed. The multivariate rate ratio (RR) of pancreatic cancer for obese women and men (BMI > or =30 kg/m(2)) was 1.81 (95% CI: 1.04-3.15) compared to those with a BMI of 20-25 kg/m(2). For a difference of 20 cm (about two standard deviations) in waist circumference, the multivariate RRs were 1.32 (95% CI: 0.73-2.37) among women and 1.74 (95% CI: 1.00-3.01) among men. Pancreatic cancer risk was associated with history of diabetes (multivariate RR: 1.88; 95% CI: 1.09-3.26) and cigarette smoking (multivariate RR for current compared with never smokers: 3.06; 95% CI: 1.99-4.72). Current smokers of > or =40 pack-years had a five-fold elevated risk compared with never smokers. Risk among past smokers approached the RR for never smokers within 5-10 years following smoking cessation. Findings from this prospective study support positive relationships of overall obesity, abdominal adiposity, diabetes and smoking with risk of pancreatic cancer.

Figure 1

Multivariate rate ratios of pancreatic cancer in relation to time since quitting of smoking among women and men. Multivariate models were stratified by age in months at baseline and sex and were simultaneously adjusted for education (less than high school, high school graduate, or more than high school), body mass index (<20.0, 20.0–24.9, 25.0–29.9, or ⩾30 kg/m²), physical activity (four categories), history of diabetes (yes or no), and alcohol consumption (quartiles).

Figure 2

Multivariate rate ratios of pancreatic cancer according to body mass index (BMI) and cigarette smoking status among women and men. Multivariate models were stratified by age in months at baseline and sex and were simultaneously adjusted for education (less than high school, high school graduate, or more than high school), physical activity (four categories), history of diabetes (yes or no), and alcohol consumption (quartiles). Nonsmoker include never and past smokers. ^*Statistically significant.