Nine RCTs, with 832 patients, were included in the review. Trial quality was generally good with all of them scoring three or more; six trials used intention-to-treat analysis. Follow-up ranged from four to 24 weeks.
Proteinuria: In four trials, oral paricalcitol statistically significantly reduced proteinuria, compared with control (RR 1.68, 95% CI 1.25 to 2.25). Subgroup analyses of 1μg (four RCTs) and 2μg (two RCTs) showed significant reductions with the paricalcitol. There was some evidence of statistical heterogeneity (Ι²=39% for all doses, 46% for 1μg, and 57% for 2μg).
Parathyroid hormone: In five trials, paricalcitol significantly decreased parathyroid hormone, compared with control (RR 6.37, 95% CI 4.64 to 8.74). Subgroup analyses by one or two 30% decreases from baseline both showed reductions in favour of paricalcitol. There was no evidence of statistical heterogeneity for these results.
Serum calcium and phosphorous: In five trials, there was a trend showing a reduction in hypercalcaemia in control groups, but this did not reach statistical significance.
There were no statistically significant differences between paricalcitol and control, in the number of patients with adverse events (six RCTs).