Potassium control in chronic kidney disease: implications for neuromuscular function

In Australia, approximately 1.7 million adults have evidence of chronic kidney disease (CKD). This complex disease can result in a multitude of complications, including hyperkalaemia, which is common and well recognised. The advent of new therapeutics aimed at lowering serum potassium has raised the possibility of optimising potassium control to enable greater use of renin-angiotensin-aldosterone system inhibitors in the management of CKD. Recent studies suggest that hyperkalaemia also has implications for peripheral neuropathy in CKD, a complication that substantially contributes to patient morbidity. This review examines evidence of the relationship between potassium and peripheral neuropathy, with a discussion of clinical implications. We searched PubMed for original and review articles using pre-specified key words, clinical guidelines and population data. The major findings were that contemporary CKD cohorts demonstrate a high prevalence of peripheral neuropathy, even in stage 3-4 CKD, including those without diabetes. The severity of the problem has been emphasised by an ominous rise in foot complications and amputation rates in dialysis patients, highlighting the need for increased awareness of the condition in earlier stages of CKD and targeted treatment strategies. It is likely that the pathophysiology of peripheral neuropathy in CKD is multifaceted, with potential influences from potassium, vascular abnormalities, diabetes, inflammation and unknown middle molecules. Despite these complexities, the relationship between potassium and nerve function in dialysis has been well established, and recent research in stage 3-4 CKD suggests that assertive potassium control may improve neuromuscular outcomes in CKD. These small studies should be confirmed in large, multicentre settings.