Benefits and harm of niacin and its analog for renal dialysis patients: a systematic review and meta-analysis.

PURPOSE: Clinical trials have shown that niacin and its analog, niacinamide, significantly reduce serum phosphate in patients undergoing dialysis. This review aimed to assess the benefits and harm of niacin and niacinamide in renal dialysis patients. METHODS: PubMed, EMBASE, and Cochrane Library were searched, without language limitation, randomized controlled trials (RCTs). Standard methods, consistent with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, were used. Reviewer Manager software, version 5.2, was used for meta-analysis. RESULTS: Five RCTs with a sample size of 230 patients were included. The meta-analysis showed that niacin and niacinamide significantly decreased serum phosphorus levels [weight mean difference (WMD) -0.88; 95 % confidence interval (CI) -1.19 to -0.57] as well as the calcium × phosphorus product (Ca × P) (WMD -9.15; 95 % CI -13.23 to -5.08), and increased high-density lipoprotein (HDL) levels (WMD 9.30; 95 % CI 5.86-12.74) in renal dialysis patients. Niacin significantly increased the risk of flushing [relative risk (RR) 33; 95 % CI 4.71-232.12] in these patients, while the risk of thrombocytopenia was significantly increased in the niacinamide group (RR 2.82; 95 % CI 1.14-6.94). However, sensitivity analysis showed that our finding regarding thrombocytopenia should be regarded with a low degree of certainty. CONCLUSION: Niacin and its analog effectively improved phosphorus metabolism in renal dialysis patients. However, niacin can cause flushing and niacinamide probably cause thrombocytopenia. Further larger sample size and well-designed RCTs are needed.