MO750: Dialysate Magnesium Impact on Progression of Coronary Artery Calcification

Abstract

Abstract BACKGROUND AND AIMS The development of vascular calcifications is accelerated in dialysis patients and is associated with an increased risk of cardiovascular morbidity and mortality. Studies have shown that magnesium (Mg) reduces mineral deposit formation, thus potentially abating the process of vascular calcification. Therefore, the use of higher dialysate-Mg might present a promising tool to reduce vascular calcification. Many in vitro studies have investigated effects of Mg on vascular calcification, but prospective clinical trials are lacking. This study evaluated the difference in coronary artery calcification progression over 12 months based on different concentrations of routinely used dialysate-Mg. METHOD This prospective randomized, multicentre study included 60 angina-free chronic haemodialysis (HD) patients distributed into two equal groups based on dialysate-Mg level (0.5 versus 1.0 mmol/L) used routinely before and throughout the study period. Laboratory measurements, including total serum Mg level and coronary artery calcium score (CACS) determined by cardiac computed tomography, were performed in all patients at baseline and after 12 months of follow-up. RESULTS Total serum Mg was significantly higher in patients on higher dialysate-Mg, both at baseline and after 12 months of follow-up (P < 0.001). Nevertheless, in both study groups, total serum Mg decreased after 12 months of follow-up; from 1.13 ± 0.15 mmol/L to 0.99 ± 0.14 mmol/L (P < 0.001) in the lower dialysate-Mg group and from 1.39 ± 0.22 mmol/L to 1.29 ± 0.21 mmol/L (P < 0.001) in the higher dialysate-Mg group. CACS increased significantly in both study groups after 12 months: from 361.90 ± 725.67 to 480.00 ± 783.53 (P <0.001) in the lower dialysate-Mg group and from 437.71 ± 573.77 to 589.07 ± 682.82 (P < 0.001) in the higher dialysate-Mg. Still, the mean change in CACS (ΔCACS) did not differ significantly between the study groups (109.29 ± 181.99 versus 151.86 ± 211.22; P = 0.321). In patients with CACS = 0 at the beginning of the study (4 in the lower and 5 in the higher dialysate-Mg group), the mean ΔCACS was 21.25 ± 3.96 and 0 (P = 0.180), respectively. CONCLUSION Routine use of higher dialysate-Mg (1.0 mmol/L) increases total serum Mg level compared with standard dialysate-Mg solutions (0.5 mmol/L). However, this was not associated with lower CACS progression over 12 months of follow-up. Further research is needed to assess if patients with CACS = 0 may benefit from higher dialysate-Mg in terms of reduced calcification progression compared with standard dialysate-Mg solutions.