Estimating Hyperkalemia Incidence Among Patients With CKD

Hyperkalemia is a common complication among patients with chronic kidney disease. However, estimates of its incidence vary. Sascha van Boemmel-Wegmann, MS, PhD, and colleagues conducted a retrospective cohort study to estimate hyperkalemia incidence in patients with CKD from routine clinical care, including by level of kidney damage or function and among subgroups. Their findings were published in Kidney Medicine.

The study included 1,771,900 US adults with CKD stages 1-4 (≥2 eGFR measurements of 15-60 mL/min/1.73 m² and/or ≥2 UACR measurements ≥30 mg/g, recorded 90-365 days apart) who were identified using the Optum de-identified electronic health records database. The median patient age was 75 years (IQR, 66-80) and 57.7% were female.

The primary study objectives were to estimate hyperkalemia incidence among patients with CKD stages 1-4, including by CKD stage, by eGFR, by UACR, and among certain patient subgroups. The subgroups identified and studied were patients with type 2 diabetes (T2D), patients without T2D or type 1 diabetes, patients with heart failure, patients prescribed steroidal mineralocorticoid receptor antagonists (sMRAs), patients prescribed renin angiotensin system inhibitors, and patients prescribed sodium-glucose cotransporter 2 inhibitors.

Hyperkalemia was defined as two elevated serum potassium values of ≥5.5 mmol/L from an inpatient setting (2-24 hours apart) or outpatient setting (maximum 7 days apart), or one elevated serum potassium value plus pharmacotherapy initiation or hyperkalemia diagnosis (maximum three days apart).

The incidence of hyperkalemia among participants was 3.37 events per 100 person-years (95% CI, 3.36-3.38) over a mean follow-up of 3.9 years. Incidence rates were higher with increased UACR and lower eGFR. The highest rates occurred among patients with UACR ≥3,500 (up to 19.1/100 person-years) regardless of decreased eGFR level. Patients with T2D (5.43/100 person-years) and heart failure (8.7/100 person-years) and patients prescribed sMRAs (7.7/100 person-years) also had high rates of hyperkalemia.

“In conclusion,” the authors wrote, “our findings suggest that UACR levels are an important factor in hyperkalemia risk stratification, in addition to eGFR levels and other known risk factors. Moreover, they underscore the importance of routinely monitoring both UACR and serum potassium levels in patients with CKD in clinical practice to help mitigate the development of hyperkalemia; particular attention should focus on patients with T2DM, heart failure, or prescribed sMRAs.”

Source: Kidney Medicine