Associations between Vitamin D and β-Cell Function and Colorectal Cancer-Associated Tumor Markers in Chinese Type 2 Diabetic Patients with Albuminuria.

BACKGROUND

This study is to investigate the protective effects of vitamin D in T2DM, as well as the associations between serum calcifediol level and β-cell function, and risk of CRC, in Chinese type 2 diabetes mellitus (T2DM) patients with albuminuria.

METHODS

Serum calcifediol levels were analyzed and compared among healthy individuals and T2DM patients stratified by albumin/creatinine ratio (ACR). Relative correlation analyses were performed with β-cell function (BCF) and risk of CRC.

RESULTS

Patients' ACR was positively associated with fasting plasma glucose and insulin, homeostasis model assessment (HOMA) of insulin resistance (IR), alpha-fetoprotein (AFP), carcinoembryonic antigen (CEA), carbohydrate antigen (CA)199, CA125, and Septin9 methylation, but inversely associated with HOMA-BCF and insulin secretion. Serum calcifediol level in the healthy controls was significantly higher than T2DM patients. In T2DM patients, calcifediol level was inversely associated with ACR, HOMA-IR, AFP, CEA, and Septin9 methylation, but positively associated with HOMA-BCF and insulin secretion. Multivariate stepwise principal component regression analysis indicated that calcifediol, hemoglobin A1c, and serum creatinine were independent risk factors for elevated CEA in T2DM.

CONCLUSIONS

Higher serum calcifediol level is correlated with better β-cell function, lower insulin resistance, and decreased risk of CRC. Vitamin D may have suppressive effects on T2DM-associated complications and therefore represents a potential prophylactic treatment against β-cell dysfunction and cancer development in T2DM patients with albuminuria.