Title: Patiromer for treating hyperkalaemia [ID877]
Funder: Department of Health and Social Care

Abstract: To appraise the clinical and cost effectiveness of patiromer within its marketing authorisation for treating hyperkalaemia.

Lay abstract: Hyperkalaemia means an abnormally high level of potassium in the blood (normal range 3.5 to 5.0 millimoles per liter [mmol/L])(1). Many people with hyperkalaemia may not have any symptoms, whilst other people have muscle weakness, muscle stiffness or fatigue. Severe hyperkalaemia can cause irregular heart beat (arrhythmia) leading to cardiac arrest and death. Hyperkalaemia usually occurs in people with impaired kidney function which may be caused by acute kidney injury or chronic kidney disease. Chronic kidney disease is prevalent among people with diabetes or chronic heart failure. Hyperkalaemia is common among people with end-stage renal disease and in older people. The risk of hyperkalaemia is increased further by medicines such as potassium supplements, inhibitors of renin–angiotensin– aldosterone system that include (angiotensin-converting-enzyme inhibitors [ACE], angiotensin II receptor blockers [ARB] and potassium-sparing diuretics). These medicines are used to treat high blood pressure and heart failure in people with chronic kidney disease. Some people with chronic kidney disease have chronic acidosis, which is treated using sodium bicarbonate which would lower the risk of hyperkalaemia (3). Between 1% and 10% of hospital inpatients have hyperkalaemia (2). Hyperkalaemia is observed in about 10% of people using ACE inhibitors and ARBs.(1) It is also present in about 5% to 10% of people having regular haemodialysis and about 10% of people with kidney failure who are not on dialysis (2). In 2013-14 there were around 7,000 hospital admissions for hyperkalaemia in England resulting in around 21,000 bed days (4). The European Resuscitation Council classifies hyperkalaemia as mild (serum potassium level of 5.5 to 5.9 mmol/l), moderate (6.0-6.4 mmol/l) or severe (6.5 mmol/l and above)(1). Treatment options for mild and moderate hyperkalaemia include a low-potassium diet and stopping medicines that cause hyperkalaemia. Further options include sodium polystyrene sulphonate or calcium polystyrene sulphonate, which reduce the levels of potassium in the body. NICE clinical guideline 108 ‘Chronic heart failure in adults: management’ recommends closely monitoring potassium, creatinine levels, and estimated glomerular filtration rate (eGFR) in people with heart failure due to left ventricular systolic dysfunction who are taking aldosterone antagonists and/or ARBs. It also recommends specialist advice, if the patient develops hyperkalaemia or renal function deteriorates. NICE clinical guideline 169 recommends that people with acute kidney injury who have hyperkalaemia that is not responding to medical management should be referred for renal replacement therapy immediately. To prevent hyperkalaemia, NICE clinical guideline 182 recommends the cautious use of renin–angiotensin system antagonists (ACE inhibitors and ARBs) in people with chronic kidney disease. References 1. European Resuscitation Council (2015) Guidelines for Resuscitation: 2015, Section 4. Cardiac arrest in special circumstances. Accessed September 2017. 2. The Renal Association (2014) Clinical Practice Guideline on Treatment of Acute Hyperkalaemia in Adults. Accessed September 2017. 3. Evans KJ, Greenberg A. Hyperkalemia: a review. J Intensive Care Med. 2005;20(5):272-90. 4. Health and Social Care Information Centre, Hospital Episode Statistics for England. Inpatient statistics, 2013-14. www.hscic.gov.uk

Research activity codes: 6.1 PHARMACEUTICALS
Health categories: BLOOD