Phosphate kinetics in Indian hemodialysis patients - an observational study

Hyperphosphatemiain endstage renal disease patients has been associated with greater risk ofmortality, especially due to cardiovascular causes (1). Most commonly,nephrologists employ an approach of dietary phosphorus restriction, use ofphosphate binders and hemodialysis, to facilitate maintenance of serumphosphate levels in dialysis patients. A majority of Indian dialysis patientsreceive two/week hemodialysis sessions, as against three/week in the Westernworld. Indian diet is vastly different from typical Western diet and variousregional differences exist too. Dietary modifications to increase protein and minimizephosphorus intake, are only variably successful, as cost and logistics play greaterrole in deciding the patient’s diet, rather than the clinician’s advice (1).Therefore, the onus of phosphate removal falls upon a combination of phosphatebinders and the hemodialysis sessions.

Briefreview: Regardingdialytic phosphorus removal, available literature is unclear whether short,frequent hemodialysis sessions are more beneficial than prolonged sessions inreducing serum phosphorus levels (2,3). To our knowledge, only a single study hasevaluated dialytic phosphorus removal over a period of time (4). This studyfound out that while the first hour of hemodialysis normalizes serum phosphoruslevels, significant amount of phosphorus continues to be removed in thesubsequent hours as well. The present study will observe dialysis phosphorusremoval at hourly intervals and help in deciding which approach will tackle hyperphosphatemia  effectively – increasing dialysis duration orfrequency. Moreover, no other study has undertaken the evaluation of dietaryphosphorus intake and dialytic phosphorus removal in an Indian populationbefore.