Background: Recently, it was reported that postmenopausal women with lower bone mineral density have an increased risk of colorectal cancer. An association between lower bone mineral density and colorectal cancer suggests that colorectal adenoma, which is a precursor of colorectal cancer, may also be associated with lower bone mineral density.
Objective: The aim of this study was to determine the association between colorectal adenoma and osteoporosis.
Design and patients: We conducted a retrospective cross-sectional study between January 2007 and May 2011. Women older than 50 years of age who underwent dual-energy x-ray absorptiometry for bone mineral density and screening colonoscopy at Gangdong Kyung Hee University Hospital in Korea during a routine health checkup were eligible for this study. We performed multivariate analysis adjusted for age, family history of colorectal cancer, alcohol consumption, current smoking, regular aspirin use, exercise, menopause, and postmenopausal hormone use to identify independent predictors for the presence of colorectal adenoma.
Main outcome measures: The primary outcome measured was the prevalence of colorectal adenoma according to the bone mineral density level.
Results: A total of 992 women older than 50 years were assigned to an osteoporosis group (n = 231) or a control group (n = 231) after menopause matching. In univariate analysis, the proportion of colorectal adenoma was significantly higher in the osteoporosis group than in the control group (29.9% vs 20.8%, p = 0.025). Furthermore, osteoporosis (OR = 1.592, 95% CI = 1.004-2.524, p = 0.048) was found to be an independent risk factor for the presence of colorectal adenoma.
Conclusions: Osteoporosis is associated with an increased risk of colorectal adenoma in women older than 50 years.