Association between Hemodialysis Patient Outcomes and Compliance with KDOQI and KDIGO Targets for Mineral and Bone Metabolism

Abstract

Background: Increased mortality of hemodialysis (HD) patients is associated with chronic kidney disease-mineral and bone disorders (CKD-MBD), and therefore, their correction may improve patient survival. Differences in targets recommended by KDOQI and KDIGO CKD-MBD guidelines directed us to compare the relative numbers of patients achieving these targets and to examine possible associations between compliance with the targets and patient outcome. Methods: A total of 1,744 patients (61.2% males, aged 58.7 ± 12.5 years) dialyzed in 20 HD centers in Serbia were monitored for 3 years. The number of participants achieving KDOQI/KDIGO guideline targets for serum phosphorus, calcium, and iPTH was determined. The Cox proportional hazards model was used to select variables significantly associated with risk of time to death. Results: A majority of patients were dialyzed thrice weekly for 4 h; 86.3% of them used phosphate binders and 49.3% vitamin D3. Proportions of patients achieving KDOQI and KDIGO targets were 49.5 and 44.4% for phosphorus, 53.2 and 76.7% for calcium, 21 and 42.8% for iPTH. Multivariate Cox analysis selected serum phosphorus level outside the KDIGO target, as well as serum iPTH levels outside KDOQI and KDIGO targets as significant mortality predictors. Areas under the receiver operating characteristic curves showed that achievement of both guideline targets for iPTH had similar survival predictive values. Conclusion: Serum phosphorus levels outside KDIGO targets and iPTH levels outside both KDOQI and KDIGO targets were associated with a significantly higher risk of death. These findings may be useful in the management of CKD-MBD and for establishing local guidelines.

Influence of pH and phosphate concentration on the phosphate binding capacity of five contemporary binders. An in vitro study

“…In spite of dietary restrictions and widespread phosphate binder use, a significant number of patients are not able to reach the target phosphate serum level. 5 There are multiple factors involved: non-compliance to the dietary restrictions and phosphate binder use, 6 bone derived phosphate and pharmacological aspects of phosphate binders. Furthermore, less acidic environment in use of proton pump inhibitors can be of influence, since lanthanum carbonate and calcium carbonate bind more phosphate in acidic surroundings.…”

“…Phosphate binders bind phosphate in the gastrointestinal (GI) tract resulting in less phosphate absorption. In spite of dietary restrictions and widespread phosphate binder use, a significant number of patients are not able to reach the target phosphate serum level . There are multiple factors involved: non‐compliance to the dietary restrictions and phosphate binder use, bone derived phosphate and pharmacological aspects of phosphate binders.…”

Targeting Gastrointestinal Transport Proteins to Control Hyperphosphatemia in Chronic Kidney Disease

“…These data suggest a causal link between hyperphosphatemia and increased mortality. The improvements in survival observed when serum abnormalities were close to the lowest risk ranges support the rationale for controlling this parameter in patients with advanced CKD [ 35 , 36 ]. However, whether this approach improves other clinical outcomes remains unproven.…”

“…Many observational studies subsequently confirmed this association between hyperphosphatemia and increased risk of mortality, but by their design all these studies precluded definite establishment of causality [ 29 – 33 ]. While no randomized controlled trials to date have demonstrated that reducing serum phosphate concentrations reduces mortality [ 34 ], a 3-year study of 1744 patients receiving dialysis identified that having serum phosphate levels above the normal range was associated with a significantly higher risk of death [ 35 ]. Additional support for the presumed causal role of hyperphosphatemia in poor outcomes comes from COSMOS (Current Management of Secondary Hyperparathyroidism: a Multicenter Observational Study), a 3-year, European, multicenter, open-cohort, observational study designed specifically to prospectively assess possible links between serum phosphate, calcium, PTH levels, and mortality risk in adults undergoing maintenance hemodialysis ( n = 6307) [ 36 ].…”

Biomarkers associated with mortality in patients undergoing dialysis

“…Predictors of a worse prognosis at the start of RRT include malnutrition and low albumin levels (Chan et al ; Takahashi et al ), frailty and comorbidity (Bao et al ; Pan et al ), age (Pan et al ), haemoglobin levels (Cherukuri & Bhandari ) and mineral metabolism disorders (Melamed et al ; Nigwekar et al ; Djukanović et al ).…”