Long-Term Vitamin D Supplementation and the Effects on Recurrence and Metabolic Status of Cervical Intraepithelial Neoplasia Grade 2 or 3: A Randomized, Double-Blind, Placebo-Controlled Trial

Objective: This study was conducted to evaluate the effects of vitamin D supplementation on the recurrence and metabolic status of patients with cervical intraepithelial neoplasia grade 2 or 3 (CIN2/3). Methods: This randomized, double-blind, placebo-controlled trial was carried out among 58 women diagnosed with CIN2/3. Participants were randomly assigned into 2 groups to receive either 50,000 IU vitamin D3 (n = 29) or placebo (n = 29) every 2 weeks for 6 months. Results: The recurrence rate of CIN1/2/3 was 18.5 and 48.1% in the vitamin D and placebo groups respectively (p = 0.02). When we excluded CIN1, the recurrence rate of CIN2/3 became nonsignificant. Vitamin D supplementation significantly decreased fasting plasma glucose (-7.8 +/- 9.2 vs. -1.1 +/- 8.6 mg/dL, p = 0.006) and insulin levels (-3.2 +/- 4.8 vs. -0.9 +/- 3.4 mu IU/mL, p = 0.03), and significantly increased quantitative insulin sensitivity check index (0.01 +/- 0.02 vs. 0.002 +/- 0.01, p = 0.02) compared with the placebo. Additionally, there was a significant decrease in high-sensitivity Creactive protein (-815.3 +/- 1,786.2 vs. 717.5 +/- 1,827.3 ng/mL, p = 0.002) and a significant increase in total antioxidant capacity (113.4 +/- 137.4 vs. -53.7 +/- 186.7 mmol/L, p < 0.001) following the supplementation of vitamin D compared with the placebo. Conclusions: Vitamin D3 supplementation for 6 months among women with CIN2/3 had beneficial effects on CIN1/2/3 recurrence and metabolic status; however, it did not affect CIN2/3 recurrence. (C) 2018 S. Karger AG, Basel