Total and Dietary Calcium Intake and Colorectal Adenoma in Korean Adults

BACKGROUND Colorectal cancer in Korea has become more prevalent over the few last decades, and calcium is considered a preventive factor for colorectal cancer development. We examined the associations between total and dietary calcium intake and the prevalence of colorectal adenoma in Korean adults. METHODS This cross-sectional study included 112 colorectal adenoma cases and 252 adenoma-free non-cases, aged 45 to 71 years, who underwent colonoscopies at the Daegu Catholic University Medical Center from August 2011 to September 2012. Participants were asked about their diet using a validated food frequency questionnaire and about supplement use through interviews. We calculated odds ratios (ORs) and 95% confidence intervals (CIs) to evaluate the association between total and dietary calcium intake and the prevalence of colorectal adenomas using multivariable logistic regression models. RESULTS Increasing total calcium intake from foods and supplements was significantly associated with a decreased prevalence of colorectal adenoma in women; comparing the highest quartile with the lowest quartile, the OR (95% CI) was 0.35 (0.15-0.85; P for trend = 0.03). Likewise, high dietary calcium intake from foods was associated with a lower prevalence of colorectal adenoma in women; compared with the lowest quartile, the ORs (95% CIs) were 0.32 (0.13-0.82) for the 3rd quartile and 0.44 (0.19-1.03; P for trend = 0.13) for the 4th quartile. However, the association was not clear for either total or dietary calcium intake among men. CONCLUSIONS A higher intake of calcium was associated with a reduction of colorectal adenoma prevalence in Korean women.