December 12, 2019
By Ian Sabir, MA, PhD, MRCP, MFPM, head of Global Medical Affairs (cardio-renal), AstraZeneca
In treating most common diseases, the focus is on the disease itself. Yet, oftentimes, co-morbid conditions and complications arise, requiring their own solutions in parallel with the treatment for the original disease. People living with chronic kidney disease (CKD) and heart failure (HF), for example, are at a higher risk of developing hyperkalemia, which can be a serious, life-threatening condition if not properly treated. Paradoxically, traditional methods for treating hyperkalemia can also lead to poor outcomes, as they are often poorly tolerated, short-term solutions that may also include the removal of life-prolonging treatment.
What is hyperkalemia?
Too much of anything is rarely good for you, and in this case, it’s potassium.
Potassium is a necessary and important electrolyte that helps regulate every heartbeat, helps muscles work correctly, and plays a role in other critical body processes. Unfortunately, excess potassium in the blood, known as hyperkalemia, can disrupt these processes and lead to serious consequences, such as cardiac arrest and death.
Who is at risk for hyperkalemia?
While a healthy body can regulate potassium levels, in the 200 million people around the world with CKD, impaired kidney function means that potassium is less effectively removed and begins to build up in the body. Individuals with both CKD and HF are at an especially high risk of developing hyperkalemia. The problem may be compounded by the use of renin-angiotensin-aldosterone system inhibitors (RAASi), a commonly used type of medication, which deliver benefits in both CKD and HF but themselves can contribute to potassium elevations.
How is hyperkalemia treated?
While acute, stark elevations in blood potassium require immediate treatment, chronic elevations are typically managed by withholding certain foods with high potassium content or certain medicines. Physicians may advise diet modification, encouraging patients to avoid otherwise-healthy foods that are high in potassium. Both adherence to and satisfaction with such diets are typically poor. Alternatively, or in addition, physicians may choose to reduce the dose or stop RAASi medicines, even though these are guideline-recommended therapies for patients with cardiovascular and renal diseases.
Direct treatment options for hyperkalemia outside of the emergency setting have historically been limited. In most countries, traditional agents that bind potassium and remove it from the body are not used as maintenance therapy for hyperkalemia very often because they are unpalatable and, in some patients, are known to have gastrointestinal safety and tolerability concerns.
Advancements in treatment
Recently additional potassium binders have become available in many countries, which can help manage hyperkalemia in these patients.
These options could be beneficial for a large number of patients, possibly allowing patients to avoid or minimize any diet restrictions and potentially allowing the maintenance and optimization of beneficial RAASi therapy. The consequences of hyperkalemia can be serious for patients with CKD or HF, and these additional treatment options could help address a significant unmet need.