The effect of cinacalcet on hypercalcemia in kidney transplant patients with hyperparathyroidism: systematic review and meta-analysis

Introduction: Following renal transplantation, patients with end-stage renal disease develop parathyroid dysfunction and electrolyte abnormalities, including calcium and phosphate levels. However, cinacalcet is one of the most used medications for hypercalcemia. Therefore, the present systematic review and meta-analysis aimed to investigate the effect of cinacalcet administration on hypercalcemia in patients with renal transplantation. Materials and Methods: The online databases of Cochrane, Web of Science, Scopus, and PubMed were searched until April 2023 using validated keywords. Moreover, PRISMA was used for qualitatively evaluating the studies since the study protocol was registered on the PROSPERO website. In addition, data analysis was conducted using Stata version 14, and the significance level was set at 0.05. Results: The present meta-analysis included 26 studies (24 cohort studies and two randomized clinical trials) investigating 602 patients with renal transplantation and hyperparathyroidism. According to our findings, cinacalcet reduced the serum calcium (MD: -2.24, 95% CI: -2.82, -1.67), parathormone (SMD: -0.85, 95% CI: -1.15, -0.54), and alkaline phosphatase levels (SMD: -0.45, 95% CI: -0.91, -0.01). Moreover, 30-60 mg of cinacalcet per day effectively treated hypercalcemia (SMD: -2.77, 95% CI: -3.57, -1.98), while other doses were not significantly effective. Furthermore, the effect of cinacalcet was investigated in patients using the medication for less than six months (SMD: -2.55, 95% CI: -4.25, -0.86), 12-18 months (SMD: -2.60, 95% CI: -3.53, -1.67), and more than 24 months (SMD: -1.71, 95% CI: -2.54, -0.88). Finally, the effect of cinacalcet was the highest in the patients who were 60-64 years old compared to other age groups (SMD: -3.59, 95% CI: -5.14, -2.04). Conclusion: Cinacalcet could improve hypercalcemia and hyperparathyroidism in patients with renal transplantation. Moreover, the effect of cinacalcet had a direct and positive relationship with the patient’s age. Registration: This study has been compiled based on the PRISMA checklist, and its protocol was registered on the PROSPERO (ID: CRD42023428620) and Research Registry (UIN: reviewregistry1667) website.