Elevated levels of the fat hormone leptin, higher body mass index (BMI), and a larger waistline are associated with a greater likelihood of having colorectal polyps in men, according to a new study. These precancerous growths can lead to colon cancer.
The result may put men at an even greater risk of the disease and also may mean their body weight could eventually be a deciding factor in whether a colonoscopy is in their future. Today, age and family history typically dictate a screening.
This 18-month, cross-sectional study followed 126 healthy, white, American males, age 48 to 65 years. The participants showed no signs or symptoms of health issues, yet they underwent routine colonoscopies. The study was published in PLoS One (2014; doi:10.1371/journal.pone.0085939).
“What we found is 78% of the 126 men in the study were either overweight or obese based on their BMI or waist circumference. Of those, about 30% were found to have more than one polyp after colonoscopies were performed,” said Jenifer Fenton, PhD, MPH, of Michigan State University in East Lansing. “In fact, the more obese participants were 6.5 times more likely to have three polyps compared to their thinner counterparts.”
The significance of the research is twofold, according to coauthor Sarah Comstock, PhD, also of Michigan State. She explained, “Not only does it show the association that leptin and a higher BMI have with colon polyps, but it gives us a better snapshot on how body weight and other factors may actually help us determine who might be at a higher risk of developing polyps.”
With obesity rates climbing during the past 20 years within the United States, and colon cancer being the second-leading killer of men and women in the nation, these facts compelled Fenton and her team to conduct research which could identify the specific biomarkers of obesity and early-stage colon cancer and help in prevention efforts.
Previous research published by Fenton in 2009 identified the connection between obesity and colon cancer through examining tissue hormones. These studies demonstrated that, at higher levels, leptin worked as a primary mechanism in inducing precancerous colon cells by increasing the blood supply to them and promoting their progression.
“Even with all of our research, there’s still more to be done, particularly in larger, more diverse populations, before any changes in screening recommendations can be made,” said Fenton. “But we’ve definitely got a good start.”