Epidemiology of hyperkalemia in chronic kidney disease

Abstract Background Hyperkalaemia is a significant electrolyte imbalance in chronic kidney disease (CKD). Renin–angiotensin–aldosterone system inhibitors (RAASi) have beneficial cardio-renal properties, although they can often cause hyperkalaemia. Objective To examine the prevalence of hyperkalaemia in CKD, identify factors associated with its appearance and the relationship between hyperkalaemia and mortality. Patients and methods Retrospective observational study on patients with CKD in the period 1971–2017. The population was categorised into 3 groups: Group 1, patients with CKD without renal replacement therapy; Group 2, patients on haemodialysis; and Group 3, patients on continuous ambulatory peritoneal dialysis. Results A total of 2629 patients were evaluated. The prevalence observed in the different groups was: 9.6%, 16.4% and 10.6%, respectively. Risk factors related to the appearance of hyperkalaemia in the CKD group were glomerular filtration rate (GFR) ( p p p p  = 0.028), diastolic blood pressure ( p  = 0.012), intake of ACE inhibitors and/or angiotensin ii receptor blockers ( p  = 0.008), treatment with metformin ( p p  = 0.045). Treatment with RAASi significantly increased hyperkalaemia as GFR decreased, as well as in patients with diabetes or heart failure. Conclusions Hyperkalaemia is a frequent metabolic alteration in CKD patients that increases in the presence of drugs with beneficial cardio-renal properties (RAASi), which means that patients often lose the benefit associated with these drugs. New, recently appearing non-absorbable compounds, which bind to potassium in the gastrointestinal tract, enhancing faecal excretion and thus maintaining the cardio-renal benefit of the RAASi, could be relevant in the progress of patients with CKD.