Serum vitamin D levels correlate with the presence and histological grading of colorectal adenomas in peri and postmenopausal women

Abstract

Vitamin D is known to modulate immune function and proliferation. Higher vitamin D [25(OH)D3] serum levels have been reported to have protective effects on adenoma detection and colorectal cancer (CRC) development and survival. 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)D3 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. A total of 77 lesions were identified in 66 patients. Vitamin D insufficiency (<30ng/mL) and deficiency (<20ng/mL) were identified in 79.4% and 35.2% of patients, respectively. In univariate analysis, lower levels of 25(OH)D3 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)D3 (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)D3 levels and lesion detection site. The association of 25(OH)D3 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.