Obesity is Killer for Seniors with Pancreatic
Cancer; More Likely to Get It if Obese When Young
Those overweight or obese from age 30 to 79 had
reduced overall survival of pancreatic cancer
Roger Giles weighed
270 pounds - 80 more than as a teen - when diagnosed with
pancreatic cancer.
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June 23, 2009 - Older people who were overweight or
obese as young adults have an increased risk of pancreatic cancer, and
seniors who are now obese have a lower overall survival rate from
pancreatic cancer, according to a new study in the June 24 issue of the
Journal of the American Medical Association.
Pancreatic cancer is the fourth leading cause of
cancer-related death for both men and women in the United States. As the
prevalence of overweight and obesity have rapidly increased during the
last 2 decades, accumulating evidence has emerged that excess body
weight is a risk factor for pancreatic cancer.
This, however, is the first study, the authors say,
that has explicitly reported the association between excess body weight
across an individual's life span and the risk of pancreatic cancer or
identified at which ages the key predisposing weight change usually
occurs."
Donghui Li, Ph.D., of the University of Texas M. D.
Anderson Cancer Center, Houston, and colleagues conducted the study to
determine the associations between body mass index (BMI) over a lifetime
and pancreatic cancer risk, age at onset, and overall patient survival.
The study included 841 patients with pancreatic
cancer and 754 healthy individuals matched by age, race, and sex. Height
and body weight histories were collected by personal interview starting
at ages 14 to 19 years and over 10-year intervals progressing to the
year prior to recruitment in the study.
● The researchers found that individuals who were
overweight (a BMI of 25-29.9) from the ages of 14 to 39 years or obese
(a BMI of 30 or greater) from the ages of 20 to 49 years had an
associated increased risk of pancreatic cancer, independent of diabetes
status.
● The association between average BMI (per 5-unit
increase) and risk of pancreatic cancer was stronger in men than in
women.
● The association was statistically significant
for each age group from 14 to 69 years in men but only from ages 14 to
39 years in women.
● The estimated association of average BMI (per
5-unit increase) with cancer risk also was slightly stronger in ever
smokers than in never smokers. It was estimated that 10.3 percent of
never smokers and 21.3 percent of ever smokers had pancreatic cancer
attributable to being overweight or obese at an early age prior to
cancer diagnosis (i.e., from the ages of 14-59 years).
● Individuals who were overweight or obese from
the ages of 20 to 49 years had an earlier onset of pancreatic cancer by
2 to 6 years (median [midpoint] age of onset was 64 years for patients
with normal weight, 61 years for overweight patients, and 59 years for
obese patients).
● Compared with those with normal body weight and
after adjusting for all clinical factors, individuals who were
overweight or obese from the ages of 30 to 79 years or in the year prior
to recruitment had reduced overall survival of pancreatic cancer
regardless of disease stage and tumor resection status.
"While our observations require confirmation, they
provide support for a role of excess body weight in the development and
progression of pancreatic cancer," the authors conclude.
In an accompanying editorial, Robert R. McWilliams,
M.D., and Gloria M. Petersen, Ph.D., of Mayo Clinic, Rochester, Minn.,
comment on the findings regarding BMI and risk of pancreatic cancer.
This study represents an incremental advance in
the understanding of clinical factors contributing to pancreatic cancer
development and progression, according to an editorial in JAMA by Robert
R. McWilliams, M.D., and Gloria M. Petersen, Ph.D., of Mayo Clinic,
Rochester, Minn.
