A significant proportion of non-dialysis chronic kidney disease (CKD) patients have inadequately managed mineral bone density (MBD), according to a new Italian study. Therapeutic inertia appears to be a barrier to good care of these patients, researchers concluded.
For the study, Maurizio Gallieni, MD, of the Nephrology and Dialysis Unit, Ospedale San Carlo A10 Borromeo, University of Milan, and colleagues prospectively evaluated CKD-MBD management in 727 non-dialysis, Caucasian patients over 2 visits occurring 6 months apart. All patients had 1 or more markers of MBD, including hyperphosphatemia, hypocalcemia, and/or hyperparathyroidism, and all were considered compliant with prescribed therapy.
According to results published online ahead of print in the Journal of Nephrology, more than 65% of the patients did not reach parathyroid hormone (PTH) targets, 19% missed calcium targets, and 15% missed phosphate targets. Each of the 19 nephrology clinics involved in the study had their own clinical targets, although most generally followed Kidney Disease Outcomes Quality Initiative (KDOQI) recommendations.
The prevalence of therapeutic inertia was 34% at 6 months. It was defined as lack of phosphate binder prescriptions despite hyperphosphatemia; lack of calcium and vitamin D supplements despite hypocalcemia; or lack of phosphate binders and calcium and vitamin D supplements despite hyperparathyroidism.
Therapeutic inertia was highest for hyperphosphatemia at 54%. For example, 51% of the 212 patients with serum phosphate greater than 4.1 mg/dL received neither phosphate binders nor a prescription for a low-protein diet. PTH was off-target in two-thirds of patients.
“This significant difference between PTH and phosphate-calcium control in the follow-up of our cohort is likely the consequences of early onset of PTH elevation in the course of CKD,” the researchers wrote.
The likelihood of inadequate treatment overall decreased as CKD worsened to stages 4 and 5 (by 40% and 68%, respectively).
The management of CKD-MBD in non-dialysis patients appears subpar, especially compared with the care of dialysis patients. The impetus for CKD-MBD prescriptions appeared to be worsening renal function rather than test results assessing each mineral.