Diabetes again linked to colon cancer risk: study
The latest study, of more than 184,000 older U.S. adults followed for up to 15 years, has again found that men with type 2 diabetes, but not women, had higher odds of developing colon cancer.
Overall, researchers found, men with diabetes were 24 percent more likely to develop the cancer than those without diabetes. Meanwhile, men who used insulin - a synthetic form of the hormone that regulates blood sugar - showed a somewhat higher risk; they were 36 percent more likely to develop colon cancer than diabetes-free men were.
And there’s evidence the link between diabetes and colon cancer risk may be weakening.
A study published last year by researchers at the American Cancer Society (ACS), and not included in the current analysis, found that among the 184,000 older U.S. residents followed for 15 years, men with type 2 diabetes were about one-quarter more likely to be diagnosed with colon cancer than diabetes-free men were.
But that increase in risk was modest, and smaller than past studies had suggested. In addition, there was no similar increase seen among women with type 2 diabetes.
The ACS researchers speculated that the findings might reflect better diabetes control among U.S. residents - and women in particular - in recent years. In theory, better blood control would mean lower insulin levels, which might affect colon cancer risk.
For now, Giovannucci recommended that people focus on maintaining a healthy weight and getting regular exercise.
The analysis included studies published from the 1990s through 2009, from the United States, Canada, Europe and Japan.
###
SOURCE: The American Journal of Gastroenterology
###
Is Diabetes Mellitus an Independent Risk Factor for Colon Cancer and Rectal Cancer?
Hiroki Yuhara MD, MPH, Craig Steinmaus MD, MPH, Stephanie E Cohen MD, MPH, Douglas A Corley MD, PhD, Yoshihiro Tei MD and Patricia A Buffler PhD, MPH
Division of Epidemiology, Berkeley School of Public Health, University of California, Berkeley, California, USA
Division of Gastroenterology, Ebina General Hospital, Kanagawa, Japan
California Environmental Protection Agency, OEHHA, Sacramento, California, USA
Division of Infectious Diseases, University of California, San Francisco, San Francisco, California, USA
Division of Research, Kaiser Permanente Northern California, San Francisco Medical Center, San Francisco, California, USA