R BOWDEN1, K MURALI1,2 K LAMBERT1,2 M SMYTH2, M LONERGAN1,2
1University of Wollongong, Wollongong, NSW 2 Illawarra Shoalhaven Local Health District
Aim: To evaluate the chronic use of Sodium Polystyrene Sulfonate (SPS) in chronic kidney disease (CKD) patients focusing on Renin-Angiotensin-Aldosterone inhibition (RAAI).
Background: Hyperkalaemia is a barrier to full implementation of RAAI. Acute treatment of hyperkalaemia with SPS is routine practice, but gastrointestinal safety concerns lead to variation in chronic use of SPS.
Methods: Patients receiving SPS from 01 Sep/2015-Sep/2016 were identified from the hospital pharmacy, which provided dosage, number of repeats and cost information. Demographics, medications and biochemistry data were obtained from the medical record. Perceived side effects and compliance data were obtained via questionnaire from a random sample of dialysis patients in the cohort.
Results: Of 432 patients using SPS, 100 (23.1%) were dialysis patients, 305 (70.6%) had CKD, 14 (3.2%) were renal transplant recipients and 13 (3.0%) had acute kidney injury. CKD patients were usually elderly (mean age76.2; SD10.8 years); male (59.3%).
Compared to a cohort of newly referred renal outpatient, CKD patients on SPS were significantly more likely to be diabetic (59% vs 36.8%, p<0.0001) and receive ACE inhibitors or angiotensin receptor blockers (74.1% vs 47.3%, p<0.0001). They had a high frequency of congestive heart failure (24.6%), beta-blocker use (54.1%) and mineralocorticoid inhibitor use (23%). No serious side effects related to SPS were identified in any patient. Stool softeners use was 18%, mainly Coloxyl and Senna. Self-reported adherence to SPS in a random sample of dialysis patients (n=35) was 71%, despite 40% (n=14) reporting unpleasant taste / texture.
Conclusions: Chronic use of SPS is safe and eases a barrier in full RAAI implementation in CKD with reasonable compliance. Newer potassium chelators should be compared to SPS for cost effectiveness and acceptability.