Abstract A56: Association between circulating 1,25(OH)2D concentration and recurrent colorectal adenoma
Authors: Hibler Elizabeth A. , Sardo Christine L. , Lance Peter , Jurutka Peter , Jacobs Elizabeth T. 
Published: May 2019

Abstract
Cellular-level studies demonstrate that availability of the steroid hormone 1α,25-dihydroxyvitamin D (1,25(OH)2D) to colon cells induces anti-carcinogenic activities. Although epidemiological data are relatively sparse, suggestive inverse trends have been reported for circulating 1,25(OH)2D concentration and risk of colorectal neoplasia. Further, recent epidemiologic work has identified an inverse association between variation in circulating concentrations of 1,25(OH)2D and fibroblast growth factor 23 (FGF23), a hormone demonstrated to interfere with the anti-carcinogenic effects of 1,25(OH)2D, indicating that concentrations of 1,25(OH)2D may vary more widely than previously thought. We therefore conducted logistic regression analysis to evaluate the relationship between variation in serum 1,25(OH)2D concentrations and characteristics of baseline and recurrent colorectal adenomas among 1,151 participants from the Ursodeoxycholic Acid clinical trial. No relationship between 1,25(OH)2D and colorectal adenoma recurrence overall was observed. However, a statistically significant inverse association was observed between circulating 1,25(OH)2D concentration and odds of proximal colorectal adenoma recurrence, with an OR (95% CI) of 0.71 (0.52-0.98) for individuals in the highest tertile of circulating 1,25(OH)2D compared to those in the lowest (p-trend = 0.04). A significantly greater proportion of women were identified in the lowest 1,25(OH)2D tertile (p&lt;0.01); however, gender did not modify the association between 1,25(OH)2D and proximal colorectal adenoma recurrence (LR-test p-value = 0.27). While there was no relationship overall between 1,25(OH)2D and recurrence of distal lesions, there was a significantly reduced odds for women in the highest tertile of 1,25(OH)2D compared to the lowest (OR=0.53; 95% CI 0.27-1.03; p-trend=0.05; p-interaction=0.08). No statistically significant associations were detected with any baseline colorectal adenoma characteristics or other classification of recurrent polyps. Associations with recurrent, as opposed to baseline lesions, may indicate that variation in circulating 1,25(OH)2D concentration influences progression of adenomas once the initiating event has occurred. The observed differences in associations with proximal and distal adenomas could indicate that delivery and activity of vitamin D metabolites in different anatomical sites in the colon may vary, particularly by gender. These results identify novel associations between 1,25(OH)2D and recurrent proximal and distal colorectal adenoma, which merit further epidemiologic studies.
Citation Format: Elizabeth A. Hibler, Christine L. Sardo, Peter Lance, Peter Jurutka, Elizabeth T. Jacobs. Association between circulating 1,25(OH)2D concentration and recurrent colorectal adenoma. [abstract]. In: Proceedings of the Twelfth Annual AACR International Conference on Frontiers in Cancer Prevention Research; 2013 Oct 27-30; National Harbor, MD. Philadelphia (PA): AACR; Can Prev Res 2013;6(11 Suppl): Abstract nr A56.