Use of the phosphate-binding drug lanthanum carbonate may increase blood pressure in patients with chronic kidney disease (CKD).
Investigators conducted a post hoc analysis of the COMBINE (CKD Optimal Management with Binders and Nicotinamide) trial including 205 patients (mean age 69 years; 38% women; 34% non-White) randomly assigned to receive lanthanum carbonate or nicotinamide, an inhibitor of active intestinal phosphate transport, or placebo. At baseline, patients had a mean estimated glomerular filtration rate of 32 mL/min/1.73 m2, serum phosphate level of 3.7 mg/dL, and blood pressure of 129/71 mm Hg. The vast majority of patients (94%) were taking antihypertensive medications.
Lanthanum carbonate users had a significant 5.52 mm Hg increase in systolic blood pressure over 12 months compared with nonusers (5.15 vs -0.37 mm Hg, respectively), Mitra S. Jamshidian, MD, MS, of the University of California, San Diego, and colleagues reported in the American Journal of Kidney Diseases. Systolic blood pressure started to increase by 3 months among recipients of the phosphate binder. No significant differences between groups were observed for diastolic blood pressure.
Dr Jamshidian’s team suggested that lanthanum carbonate reduces gastrointestinal absorption of antihypertensive medications either directly or indirectly. They noted that the FDA approval for lanthanum carbonate warns that the drug may impair absorption of angiotensin-converting enzyme inhibitors (ACEI) and recommends against their concurrent use.
“Given the widespread use of phosphate binders in CKD, the very high prevalence of hypertension, FDA warnings about co-administration of [lanthanum carbonate] with ACEI, and the large magnitude of change in SBP we observed, future studies to confirm these findings and determine the mechanisms should be a high priority.”
Jamshidian MS, Larive B, Gassman J, et al. Effect of lanthanum carbonate on blood pressure in CKD. Published online January 8, 2021. Am J Kid Dis. doi:10.1053/j.ajkd.2020.12.012