Lower mortality in calcimimetic users compared to non-users in dialysis patients with serum parathyroid hormone levels within the target range

Lower serum parathyroid hormone (PTH) levels are reported to improve mortality and fracture incidence in patients using calcimimetics. We investigated the prognosis of calcimimetic users and non-users with similar PTH levels within the target range. This retrospective study compared 2-year all-cause mortality and the incidence of any fracture in dialysis patients between calcimimetic users (n = 131) and non-users (n = 294) with PTH levels between 60 and 240 pg/mL using a propensity score-matched model. Kaplan-Meier survival curves censored by PTH level, calcimimetic use, and other factors were compared; then, adjusted Cox proportional hazards regression analysis was performed. After matching, mortality was significantly lower in calcimimetic users than in non-users (n = 130; hazard ratio [HR] 0.243, 95% confidence interval [CI] 0.073-0.801, P = 0.022, log-rank test). The PTH levels of users and non-users were 142.4 ± 49.4 and 132.7 ± 48.0 pg/mL, respectively (P = 0.127). Cox regression analysis demonstrated that mortality was significantly lower in users than in non-users (adjusted HR 0.260, 95% CI 0.071-0.947, P = 0.041). Calcimimetic use had no effect on fracture incidence. These findings suggest that, among dialysis patients with PTH levels between 60 and 240 pg/mL, mortality risk was significantly lower among calcimimetic users than in non-users. However, fracture risk was not significantly different between these groups.