Can an Active Lifestyle Lower the Risk of Pancreatic Cancer?

Pancreatic cancer is the fourth leading cause of death from cancer in the United States. Smoking, diabetes, and obesity are associated with increased risk for the disease. Little is known, however, about lifestyle practices that may play a role in lowering the risk. Research suggests that high glucose levels and decreased insulin sensitivity observed in obese people, and those with early-stage diabetes may cause damage to pancreatic cells, increasing the risk of cancer. Results from several studies have associated even small increases in physical activity with improved insulin sensitivity. An active lifestyle may also provide added protection against pancreatic cancer. Several studies have demonstrated a significant inverse association between greater amounts of physical activity and reduced pancreatic cancer risk. Other studies, however, have not proven such a relationship. The variation in study results may be influenced by the parameters established for each individual study. Researchers from the Division of Cancer Epidemiology and Genetics, at the National Cancer Institute (NCI) evaluated the relationship between light, moderate, and vigorous physical activity, along with overal total physical activity, and the risk of pancreatic cancer. The authors of the study reported on their findings in BMC Cancer.

Study participants were already enrolled in a breast cancer mammography screening program sponsored by the NCI and the American Cancer Society. The information used for the pancreatic cancer study was self-reported by each participant, and pertained to their physical activity level, smoking habits, and diet. Individuals provided estimates on the number of hours they spent in light, moderate, and vigorous physical activity. Each activity was analyzed separately for its association with pancreatic cancer.

From a total of 33,350 female participants, 70 cases of pancreatic cancer were found to have occurred over the study period. Results showed an overall association between higher levels of physical activity and lowered pancreatic cancer risk. When comparing the risk for participants who reported the lowest levels of total physical activity with women who reported the highest levels of activity, the authors determined a decrease in risk associated with higher levels, although only of marginal statistical significance. In general, women who were more active had a lower body mass index, smoked less, and reported no history of diabetes when compared with women who reported being less active. After statistical adjustments for age, the authors found a significant inverse dose-response relationship, where higher activity levels indicated decreased risk.

The significance of this study is that it was the first to report on the association between physical activity and pancreatic cancer risk by measuring the amount and intensity of recreational, occupational, and household activity combined. The authors suggest that a measure of household activity level is a particularly relevant one for a study consisting of only women. The wide range of activity types and measures of both quantity and intensity may offer a more solid data set upon which to base conclusions. The authors assert that their results may have been influenced by the fact that physically active individuals often consume healthy diets and maintain healthy body weight, factors that may already contribute to decreased risk. Despite conflicting results regarding pancreatic cancer, a great deal of evidence has been gathered over time to prove that an active lifestyle and healthful diet are key to living a healthy life.

Reference

Calton, R., Stolzenberg-Solomon, R., Moore, S., Schatzkin, A., Schairer, C., Albanes, D., Leitzman, M.

A prospective study of physical activity and the risk of pancreatic cancer among somen (United States)

BMC Cancer, http://www.biomedcentral.com/bmccancer/

http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pubmed&pubmedid=18307811