Nutritional status and survival of maintenance hemodialysis patients receiving lanthanum carbonate.

Background: Hyperphosphatemia and poor nutritional status are associated with increased mortality. Lanthanum carbonate is an effective, calcium-free phosphate binder, but little is known about the long-term impact on mineral metabolism, nutritional status and survival.
Methods: We extended the follow-up period of a historical cohort of 2292 maintenance hemodialysis patients that was formed in late 2008. We examined 7-year all-cause mortality according to the serum phosphate levels and nutritional indicators in the entire cohort and then compared the mortality rate of the 562 patients who initiated lanthanum with that of the 562 propensity score-matched patients who were not treated with lanthanum.
Results: During a mean ± SD follow-up of 4.9 ± 2.3 years, 679 patients died in the entire cohort. Higher serum phosphorus levels and lower nutritional indicators (body mass index, albumin and creatinine) were each independently associated with an increased risk of death. In the propensity score-matched analysis, patients who initiated lanthanum had a 23% lower risk for mortality compared with the matched controls. During the follow-up period, the serum phosphorus levels tended to decrease comparably in both groups, but the lanthanum group maintained a better nutritional status than the control group. The survival benefit associated with lanthanum was unchanged after adjustment for time-varying phosphorus or other mineral metabolism parameters, but was attenuated by adjustments for time-varying indicators of nutritional status.
Conclusions: Treatment with lanthanum is associated with improved survival in hemodialysis patients. This effect may be partially mediated by relaxation of dietary phosphate restriction and improved nutritional status.