Abstract: 【Abstract】Objective Hyperkalemia is a common complication in patients with end stage renal disease due to impaired renal potassium excretion. Higher pre-dialysis serum potassium may cause heart rhythm disturbances and even fatal cardiac arrest. This study assessed the prevalence of hyperkalemia in hemodialysis (HD) patients based on the China Dialysis Outcomes and Practice Patterns Study (DOPPS), and explored the independent risk factors of hyperkalemia in HD patients. Methods DOPPS is an international prospective and observational study. China participates in the DOPPS5 (2012～2015) and has completed the follow-up study of the cohort. A total of 1,427 HD patients included in the China DOPPS5. We recruited their pre-dialysis serum potassium and clinical data, and divided them into normal potassium group and hyperkalemia group (serum potassium ≥5.5mmol/L). Their demographic information, laboratory data and dialysis prescriptions were compared between the two groups. The independent risk factors for hyperkalemia were explored using multivariate logistic regression analysis. Results A total of 1,339 HD patients were enrolled in this study, with an average age of 59.4±14.9 years, 54.4% males, and an average dialysis vintage of 2.6 (0.9, 5.3) years. Hyperkalemia was detected in 345 patients (25.8%), of which 13.3% were mild hyperkalemia, 7.6% were moderate hyperkalemia, and 4.9% were severe hyperkalemia. Among the three cities involved in this study, the HD patients in Beijing had the highest rate of hyperkalemia (31.8%), followed by Guangzhou (26.0%) and Shanghai (19.3%) (χ2=18.580, P＜0.001). There were significant differences in age (t=2.610, P=0.009), gender (χ2=4.059, P=0.007), BMI (t=-2.680, P=0.008), dialysis adequacy (t=4.280, P＜0.001), dialysis frequency (χ2=21.548, P＜0.001), serum albumin (t=6.071, P＜0.001), and serum phosphorus (t=7.083, P＜0.001) between normal potassium group and hyperkalemia group. Multivariate logistic regression showed that higher
BMI (OR: 1.040, 95% CI: 1.004～1.077, P=0.027), female gender (OR:1.201, 95% CI: 1.023～2.547, P=0.026), potassium concentration in dialysate≥2.5mEq/L (compared to <2.5mEq/L) (OR: 1.194, 95% CI:1.028～1.386, P=0.020), lower dialysis adequacy (stdKt/V<2) (OR: 1.336, 95% CI: 1.170～1.527, P＜0.001), dialysis frequency＜3 times per week (OR: 1.332, 95% CI: 1.150～1.544, P＜0.001), higher serum albumin (OR: 1.815, 95% CI: 1.294～2.547, P＜0.001) and higher serum phosphorus (OR: 1.231, 95% CI: 1.153～1.316, P＜0.001) were the independent risk factors for hyperkalemia in HD patients (P＜0.05). Conclusion
The China DOPPS5 of hyperkalemia in HD patients found that hyperkalemia was detected in 25.8% HD patients. Among the three cities involved in this study, the HD patients in Beijing had the highest rate of hyperkalemia (31.8%), followed by Guangzhou (26.0%) and Shanghai (19.3%). Higher BMI, female gender, dialysate potassium concentration≥2.5mEq/L, stdKt/V＜2, dialysis frequency＜3 times per week, higher serum albumin and phosphorus levels were the independent risk factors for hyperkalemia in HD patients.

Key words: Hemodialysis, Hyperkalemia, DOPPS