Survival advantage of lanthanum carbonate for hemodialysis patients with uncontrolled hyperphosphatemia.

BACKGROUND: Lanthanum carbonate is a non-calcium phosphate binder that is effective for the treatment of hyperphosphatemia. However, it is unknown whether treatment with lanthanum affects survival.

METHODS: We retrospectively collected data on maintenance hemodialysis patients at 22 facilities (n = 2292) beginning in December 2008, a time point immediately prior to the commercial availability of lanthanum in Japan. We compared 3-year all-cause mortality among patients who initiated lanthanum (n = 560) and those who were not treated with lanthanum during the study period (n = 560) matched by the propensity score of receiving lanthanum. Several sensitivity analyses were performed to test the robustness of the primary analysis.

RESULTS: After the market introduction of lanthanum, the percentage of patients receiving the binder increased gradually to 27%. In the propensity score-matched analysis, the mortality rate for the lanthanum group was not significantly lower than the non-lanthanum group [hazard ratio (HR), 0.71; 95% confidence interval (CI), 0.47-1.09). However, stratification by serum phosphorus disclosed significant survival benefit of lanthanum for patients with serum phosphorus >6.0 mg/dL (HR, 0.52; 95% CI, 0.28-0.95), but not in patients with serum phosphorus ≤6.0 mg/dL (HR, 1.00; 95% CI, 0.55-1.84). The survival benefit of lanthanum in patients with serum phosphorus >6.0 mg/dL was consistent across subgroups and robust in different analytical approaches.

CONCLUSIONS: Treatment with lanthanum was independently associated with a significant survival benefit in hemodialysis patients with inadequately controlled hyperphosphatemia. Further studies are required to confirm these findings.