Adenoma recurrence more likely among the overweight

Oct 17, 2010

Overweight patients have a higher recurrence rate for colonic adenomas over both the short and long term, concluded a study presented this week at the 2010 American College of Gastroenterology (ACG) annual meeting held in San Antonio.

Previous prospective studies have evaluated the association between obesity and colorectal adenoma recurrence within four years of follow-up, which is a relatively short duration, according to lead researcher Adeyinka Laiyemo, MD. The authors wanted to look at the long-term risk of adenoma recurrence among participants in the Polyp Prevention Trial (PPT), a multicenter, randomized, controlled trial that evaluated the effect of a low-fat, high-fiber, high fruit-and-vegetable diet on the risk of colorectal adenoma recurrence.

A total of 760 participants (mean age, 59.7 years; 66% male) with colorectal adenomas at baseline had their body mass index (BMI) measured and completed a four-year trial that included repeat optical colonoscopy at one year and four years after the study began. At baseline, approximately half of the 760 participants were overweight (BMI = 25-29 kg/m²) and 25% were obese (BMI = 30 kg/m²).

After the four-year trial was complete, participants were followed with colonoscopy reports obtained after the trial results were analyzed. Adenoma recurrence was defined as any adenoma detected after the baseline colonoscopy. The study team used Poisson regression models to evaluate risk of adenoma recurrence up to four years (defined as short-term) and approximately 12 years of follow-up (mean, 8.4 years; range, 4.9-12.4 years).

"When compared with participants with normal BMI, overweight and obese participants have an elevated risk of adenoma recurrence during both short-term and long-term," Laiyemo said.

Adenoma recurrence during short- and long-term follow-up according to baseline BMI

		Relative risk and 95% CI for adenoma recurrence within 4 years vs. no recurrence		Relative risk and 95% CI for adenoma recurrence within 12.4 years vs. no recurrence
Baseline BMI	n (%)	Any adenoma, n = 428	Advanced adenoma, n = 91	Any adenoma, n = 500	Advanced adenoma, n = 122
< 25	189 (24.9)	1.0	1.0	1.0	1.0
25-29	378 (49.7)	1.23 (1.03-1.46)	1.18 (0.75-1.85)	1.18 (1.02-1.36)	1.14 (0.80-1.61)
≥ 30	193 (25.4)	1.19 (0.98-1.45)	1.23 (0.73-2.07)	1.20 (1.03-1.41)	1.25 (0.83-1.88)

Models were adjusted for age, sex, nonsteroidal anti-inflammatory drug use, smoking, and family history of colorectal cancer. CI = confidence interval.

"Since BMI was positively associated with adenoma recurrence in short- and long-term, lifestyle modification should be encouraged," Laiyemo said.

By Eric Barnes
AuntMinnie.com staff writer
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