A pooled analysis of 14 cohort studies of anthropometric factors and pancreatic cancer risk

Abstract

Epidemiologic studies of pancreatic cancer risk have reported null or nonsignificant positive associations for obesity, while associations for height have been null. Waist and hip circumference have been evaluated infrequently. A pooled analysis of 14 cohort studies on 846,340 individuals was conducted; 2,135 individuals were diagnosed with pancreatic cancer during follow-up. Study-specific relative risks (RRs) and 95% confidence intervals (CIs) were calculated by Cox proportional hazards models, and then pooled using a random effects model. Compared to individuals with a body mass index (BMI) at baseline between 21-22.9 kg/m 2 , pancreatic cancer risk was 47% higher (95%CI:23-75%) among obese (BMI 30 kg/m 2 ) individuals. A positive association was observed for BMI in early adulthood (pooled multivariate [MV]RR 5 1.30, 95%CI 5 1.09-1.56 comparing BMI 25 kg/m 2 to a BMI between 21 and 22.9 kg/m 2 ). Compared to individuals who were not overweight in early adulthood (BMI < 25 kg/m 2 ) and not obese at baseline (BMI < 30 kg/m 2 ), pancreatic cancer risk was 54% higher (95%CI 5 24-93%) for those who were overweight in early adulthood and obese at baseline. We observed a 40% higher risk among individuals who had gained BMI 10 kg/m 2 between BMI at baseline and younger ages compared to individuals whose BMI remained stable. Results were either similar or slightly stronger among never smokers. A positive association was observed between waist to hip ratio (WHR) and pancreatic cancer risk (pooled MVRR 5 1.35 comparing the highest versus lowest quartile, 95%CI 5 1.03-1.78). BMI and WHR were positively associated with pancreatic cancer risk. Maintaining normal body weight may offer a feasible approach to reducing morbidity and mortality from pancreatic cancer.

Body mass index, abdominal fatness and pancreatic cancer risk: a systematic review and non-linear dose–response meta-analysis of prospective studies

“…However, with a larger number of studies, we also found significant associations among both men and women and among American, European and Asian studies and there was no evidence of a difference between the summary estimates for these subgroups, confirming the importance of body weight control for pancreatic cancer prevention in diverse populations and among both genders. Two pooled analyses (64;65) and a meta-analysis (3) have previously reported somewhat stronger associations among women than among men, while our meta-analysis and another pooled analysis (66) showed similar results in men and women. The difference between our findings and the previous analyses may relate to the larger number of studies now available and therefore more statistical power to detect an association also among men.…”

Hormonal factors and pancreatic cancer risk in women: The Malmö Diet and Cancer Study

“…As mentioned, several studies present results showing an increased risk of pancreatic cancer with increasing BMI,13, 21, 22, 23 which has not been observed in the MDCS, neither in men nor in women 42. Still, adipose tissue is also known to produce estrogens, thus suggesting it may play a protective role as well.…”

“…Tobacco smoking,4, 5, 6 high age4, 7, 8 and heredity9, 10 seem to be the only truly validated risk factors for pancreatic cancer. Several other risk factors have been investigated, and numerous studies claim a significant impact of diabetes,11, 12, 13 pancreatitis,14, 15, 16 alcohol17, 18, 19, 20 and body mass index (BMI)13, 21, 22, 23; however, no consensus has yet been reached.…”

Adipose tissue, obesity and adipokines: role in cancer promotion

“…Postmenopausal obesity is a predictor of fatal breast cancer [9] and increased risk for endometrial cancer [10] and ovarian cancer [11]. Much like the other cancers, obesity also increases pancreatic cancer risk [12,13]. Other studies indicate, however, that weight lossin particular that accompanying with gastric bypass -is associated with reduced cancer risk when compared to those without surgery [14].…”