HOUSTON - In reviewing the weight history of pancreatic cancer patients across their life spans, researchers at The University of Texas M. D. Anderson Cancer Center have determined that a high body mass index in early adulthood may play a significant role in an individual developing the disease at an earlier age.
The study, published in the June 24 issue of the Journal of the American Medical Association, also found that patients who are obese the year before diagnosis have a poorer outcome than those who are not.
While excess weight is a known risk factor associated with pancreatic cancer, before now, few studies have looked at patients' body mass index (BMI) throughout their lifetime rather than simply at adulthood and/or year of disease diagnosis.
Of course there's the possibility that genes that boost obesity risk also boost cancer risk. Or heavier weight reduces exercise that somehow boosts cancer risk. But there's a decent chance here that obesity more directly boosts pancreatic cancer risk. Eat accordingly.
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.
The problem with applying this result to your life is that most dieters gain back their lost weight. Conscious weight control is very difficult and most people fail at it.
In my mind the main purpose of cancer risk reduction is to delay getting cancer until when it becomes curable.
Interventional studies provide stronger evidence than population studies that just find correlations bewteen two factors. Well, with that thought in mind if you doubt that weight reduction can cut cancer risk consider a new study from Sahlgrenska University Hospital in Sweden,which found that in women (though curiously not in men) bariatric surgery (e.g. stomach staples) cut the incidence of cancer in women.
New evidence suggests that obese women could lower their risk of cancer over 40 percent by undergoing weight-loss operations that involve stapling the stomach or small intestine.
So a good appetite suppressant drug will probably some day cut the incidence of cancer.
Update: Parenthetically, the mortality rates from bariatric surgery are now pretty low.
DURHAM, N.C. -- Advances in weight-loss surgery have made it as safe as any routine surgical procedure, according to a Duke University Medical Center researcher who reviewed data from nearly 60,000 patients and found it resulted in low complication and mortality rates.
The analysis, compiled from the largest repository of bariatric surgery patients ever recorded, indicates complication rates hover around 10 percent – with the most common complaint being nausea/vomiting. Total mortality rate was under one percent (0.135%) with 78 deaths reported among 57,918 patients.
Note that surgeons who perform a procedure frequently make fewer mistakes. So if you are considering bariatric surgery look for a surgeon who specializes in it.
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