ASPO Abstracts
Lifetime BMI, central adiposity and pancreatic cancer risk in a large US cohort
Category: Lifestyles Behavior, Energy Balance & Chemoprevention
Conference Year: 2021
Abstract Body:
Purpose: To examine the association with body mass index (BMI) at different ages and three measures of abdominal adiposity
and pancreatic ductal adenocarcinoma (PDAC) risk in US adults aged 51-70 years (y).
Methods: We calculated BMI, and used three measures of abdominal adiposity, including waist circumference (WC), waist-to-hip
ratio (WHR) and a new body shape index (ABSI) from a risk factor questionnaire in 1995-1996 in the NIH-AARP Diet and Health
Study. We included subjects with self-reported height and weight (N=270,722; 163,873 men, 106,849 women) at ages 18, 35,
50y and at baseline. A subset of participants self-reported abdominal adiposity measures: waist and hip circumference
(n=197,461; 123,991 men, 73,470 women). Cox proportional hazard models adjusted for age, sex, and smoking were used to
estimate hazard ratios (HR) and 95% confidence intervals (CI) corresponding to BMI per 5 kg/m², WC per cm, WHR, and ABSI
with PDAC risk. Within each age category, participants with BMI < 18.5 kg/m² were excluded from the analyses.
Results: Over an average follow-up time of 13.1y (max: 15.17 y), 3,105 incident PDAC cases (2,033 men, 1,072 women) were
identified in the overall cohort, and 2,297 cases (1,534 men, 763 women) with abdominal adiposity measures. A 5-unit increase
in BMI was significantly associated with increased PDAC risk [HR (95%CI)] at 18y [1.10 (1.04, 1.17)], 35y [1.07 (1.02, 1.13)], 50y
[1.08 (1.04, 1.13)], and baseline age [1.06 (1.02, 1.10)]. This association was stronger in men at 18y [1.11 (1.03, 1.20)], 35y [1.11
(1.04, 1.18)], 50y [1.12 (1.06, 1.19)], and baseline age [1.09 (1.04, 1.15)], but not in women (P-interaction < 0.05 by sex only at
50y). WC per cm increase was significantly associated with increased PDAC risk in sex-combined models [1.01 (1.00, 1.01)],
men [1.01 (1.00, 1.02)], and women [1.01 (1.00, 1.02)]; interactions were not significant. WHR and ABSI were not significantly
associated with PDAC.
Conclusions: We confirm that increasing adult BMI at ages 18, 35, 50, and > 50 is associated with PDAC with associations
stronger in males compared to females. Of the three measures of central adiposity, only WC, which is correlated with BMI, is
significantly associated with PDAC.
Keywords: Body Mass Index, Pancreatic Cancer, Adiposity