Serum Vitamin D Levels Correlate with the Presence and Histological Grading of Colorectal Adenomas in Peri and Postmenopausal Women.

Background & aims: Vitamin D is known to modulate immune function and proliferation. Higher vitamin D [25(OH)D-3] serum levels have been reported to have protective effects on adenoma detection and colorectal cancer (CRC) development and survival. Methods: This retrospective cohort study included 315 peri and post-menopausal women submitted to opportunistic colorectal and osteoporosis screening at the gynaecology outpatient clinic of a tertiary medical centre between 2004 and 2015. Colonoscopy findings were correlated with 25(OH)D-3 and PTH serum levels, and subsequently adjusted in a multivariate logistic regression model. Confounding factors included demographic and colorectal risk factors, pharmacological therapies and bone densitometry metrics. Results: A total of 77 lesions were identified in 66 patients. Vitamin D insufficiency (<30 ng/mL) and deficiency (<20 ng/mL) were identified in 79.4% and 35.2% of patients, respectively. In univariate analysis, lower levels of 25(OH)D-3 were associated with polyp, adenoma and advanced adenoma detection. After adjusting for confounders, an association with polyps could not be observed, but a trend towards a negative correlation with adenoma detection was found (adjusted OR: 0.96; 95% CI 0.92-1.00; p = 0.083). Regarding advanced adenoma detection, 25(OH)D-3 (adjusted OR: 0.86; 95% CI 0.77-0.97; p = 0.013) proved to be an independent predictive factor. No association was found between 25(OH)D-3 levels and lesion detection site. Conclusion: The association of 25(OH)D-3 serum levels with colorectal lesions seems to be restricted to adenomatous lesions and is influenced by histological grading. Vitamin D may be a valuable biomarker for optimization of risk stratification in group-specific CRC screening protocols. (C) 2018 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.