Associations Between Dietary Potassium Intake From Different Food Sources and Hyperkalemia in Patients With Chronic Kidney Disease

Abstract

Objective

Previous studies reported mixed results on associations between dietary potassium intake and hyperkalemia in patients with chronic kidney disease (CKD). This study investigated the association between potassium intake from different food sources and hyperkalemia in patients with non-dialysis-dependent CKD.

Methods

A total of 285 patients were recruited at a university hospital and two city hospitals in Tokyo. Dietary potassium intake was estimated by a validated diet history questionnaire. Associations of potassium intake from all foods and individual food groups with serum potassium were examined by multivariable linear regression among potassium binder non-users. An association between tertile groups of potassium intake and hyperkalemia, defined as serum potassium ≥5.0 mEq/L, was evaluated by multivariable logistic regression.

Results

Among 245 potassium binder non-users, total potassium intake was weakly associated with serum potassium (regression coefficient=0.147, 95% confidence interval (CI): 0.018–0.277), while an association with hyperkalemia was not observed (first vs third tertile: adjusted odds ratio (aOR) = 0.98, 95% CI: 0.29–3.26). As for food groups, potassium intakes from potatoes, pulses, and green/yellow vegetables were positively associated with serum potassium. Patients in the highest tertile of potassium intake from potatoes had higher odds of hyperkalemia as compared to those in the lowest tertile (aOR = 4.12, 95% CI: 1.19–14.34).

Conclusion

Total potassium intake was weakly associated with serum potassium, but not with hyperkalemia. Potassium intake from potatoes was associated with hyperkalemia. These findings highlight the importance of considering food sources of potassium in the management of hyperkalemia in CKD.