[Prevalence and related factors of hyperkalemia in patients with diabetic kidney disease]

Objective: To explore the prevalence and related factors of hyperkalemia in patients with diabetic kidney disease (DKD). Methods: DKD patients from the Department of Nephrology of the First Affiliated Hospital of Zhengzhou University from January 2012 to December 2020 were selected, and the clinical data of the patients were retrospectively collected. The prevalence of hyperkalemia in DKD patients and the prevalence of hyperkalemia in patients with different age, gender and different stages of chronic kidney disease (CKD) were studied, and the related factors of hyperkalemia were further explored. Results: A total of 1 721 patients with DKD were included, with 1 117 males (64.9%) [mean age: (56±12) years] and 604 females (35.1%) [mean age: (59±12) years]. The blood potassium level of the study population was (4.93±0.77) mmol/L, in which the serum potassium level of male and female was (4.92±0.77) mmol/L and (4.93±0.76) mmol/L, respectively, and the difference was not statistically significant (P=0.752). Further grouping by CKD stage, the serum potassium levels of CKD stage 1-5 patients were (4.58±0.52), (4.65±0.47), (4.86±0.59), (5.21±0.79) and (5.61±0.88) mmol/L, respectively, and the difference was statistically significant (F=170.701, P<0.001). The prevalence of hyperkalemia was 37.0% (636/1 721). The prevalence of mild, moderate and severe hyperkalemia was 17.4%, 10.5% and 9.1%, respectively. There was no significant difference in the prevalence of hyperkalemia between men and women (36.8% vs 37.3%, χ²=0.035, P=0.851). The prevalence of hyperkalemia in CKD stage 1-5 patients was 16.3%, 21.2%, 37.6%, 55.2%, 72.5%, respectively, which increased with the severity of CKD (χ²=365.721, P<0.001). Multivariate logistic regression showed that estimated glomerular filtration rate (OR=0.975, 95%CI: 0.972-0.979), diastolic blood pressure (OR=0.985, 95%CI: 0.975-0.994) and serum sodium concentration (OR=0.972, 95%CI: 0.945-1.000) were the influencing factors of hyperkalemia in DKD patients. Conclusions: The prevalence of hyperkalemia in DKD patients was 37.0%. Glomerular filtration rate, diastolic blood pressure and serum sodium concentration were the influencing factors. The serum potassium level and the prevalence of hyperkalemia increased with the deterioration of renal function.