RESUMEN
This study was conducted to assess the effect of oral calcitriol on glucose metabolism in patients on hemodialysis (HD). A total of 27 patients on HD at the Mashhad University of Medical Sciences, Iran, none of whom had received calcitriol or had history of diabetes, were selected. The patients were randomly divided into two groups; Group I: patients who received oral calcitriol for eight weeks and, Group II: patients who received placebo. In all cases, levels of fasting glucose, insulin, lipid profile, calcium, phosphorous, parathormone (PTH), HbA1C and blood sugar after administration of 75 grams of glucose, insulin resistance and beta cell function were measured, before and after the treatment period. The two sets of results were then compared with one another. In Group l patients, the levels of the parameters studied before and after the study period were as follows: blood sugar after 75 grams of glucose (88.67 +/- 8.68 versus 99.83 +/- 34.42 mg/dL, p = 0.045), HOMA-IR (2.05 +/- 1.42 versus 2.42 +/- 1.33, p = 0.035), HbA1C (5.99 +/- 1.00 versus 6.14 +/- 1.19, p= < 0.001), total cholesterol (153.3 +/ 43.80 mg/dl versus 157.0 +/52.62, p = 0.037) and triglycerides (175.30 +/- 99.65 versus 214.9 +/- 117.7 mg/dL, p = 0.036). Thus, there was a significant decrease after the study period. In Group II, fasting blood sugar (110.7 +/- 26.12 versus 81.14 +/- 13.31 mg/dL, p = 0.002), HbA1C (6.99 +/- 1.44 versus 6.17 +/- 1.66, p = 0.004) and HOMA-IR (5.85 +/- 5.11 versus 3.20 +/- 2.39, p = 0.036) significantly increased and beta cell function significantly decreased (149.5 +/- 90.57 versus 355.7 +/- 299.3, p = 0.032) after the study period. In conclusion, our results show that vitamin D has a significant influence on glucose metabolism. Similar studies on larger sample size are required to confirm this observation.