Abstract: Objective To explore the risk factors for secondary hyperkalemia after potassium supplementation in the elderly patients with hypokalemia. Methods A total of 648 elderly patients with hypokalemia who were hospitalized in China Rehabilitation Research Center(Beijing Bo'ai Hospital) from January to December 2020 were consecutively enrolled. The patients presenting with secondary hyperkalemia after potassium supplementation were enrolled into the secondary hyperkalemia group, and the other patients were enrolled into the control group. The clinical data of two groups were collected for retrospective analysis. Binary Logistic regression analysis was used to analyze the rise factors for hyperkalemia in the elderly patients with hypokalemia. Results The incidence rate of secondary hyperkalemia after potassium supplementation in the elderly patients with hypokalemia was 11.6%(75/648). The age, prevalence rate of stroke and chronic renal insufficiency, baseline level of blood potassium, the rate of oral potassium supplementation and the usage rate of insulin and antibiotics were significantly higher while the levels of estimated glomerular filtration rate(eGFR) and hemoglobin(Hb) were significantly lower in the elderly patients with hypokalemia followed by hyperkalemia than those in the control group(P<0.05). Binary Logistic regression analysis showed that eGFR<60 mL/(min·1.73m²)(OR=2.49, 95%CI:1.43-4.32), Hb<90 g/L(OR=2.86, 95%CI:1.49-5.51), high baseline serum potassium level(OR=1.78,95%CI:1.09-2.92), insulin use(OR=2.57,95%CI:1.47-4.50) and antibiotic use(OR=2.39, 95%CI:1.05-5.43) were the risk factors for hyperkalemia after hypokalemia in the elderly patients. Conclusions The elderly patients with hypokalemia have a high risk of hyperkalemia after potassium supplementation, and potassium supplementation should be used with caution in these patients.

Key words: aged, hypokalemia, hyperkalemia, risk factors