Prevalence,Recurrence, Risk Factors and Adverse Clinical Outcomes of Hyperkalemia in Maintenance Hemodialysis Patients

Background The study aimed to investigate the prevalence, recurrence, and risk factors associated with serum potassium levels in patients undergoing maintenance hemodialysis (MHD), as well as to explore the correlation between hyperkalemia (HK) and adverse clinical outcomes. Methods A cohort of 499 patients was enrolled in this study. Comprehensive data collection was performed,encompassing serum potassium levels, laboratory parameters, comorbid conditions, and medication regimens. The primary endpoints included major adverse cardiovascular events (MACEs), defined as a composite of hospitalizations for unstable angina, nonfatal myocardial infarction, sustained ventricular arrhythmia, congestive heart failure, transient ischemic attack, or stroke. Secondary outcomes comprised all-cause hospitalizations. Both univariate and multivariate logistic regression analyses were conducted to identify risk factors associated with HK and its recurrence in MHD patients. Furthermore, the study evaluated the potential association between elevated serum potassium levels and the risk of MACEs or hospitalization events. Results A total of 499 MHD patients with 1812 records wereincluded in this analysis during the follow-up period of 4 years. The prevalence of HK, stratified by serum potassium thresholds of ≥5.0, ≥5.5, and ≥6.0 mmol/L, was 55.11%, 27.66%, and 11.62%, respectively. Recurrent HK, defined as at least two episodes of serum potassium ≥5.0 mmol/L, was observed in 53.09% of the hyperkalemia patients. Multivariate logistic regression models for HK revealed that gender, dialysis duration, Kt/v, creatinine and treatment with ACEI or ARB drugs were associated with increased serum potassium odds. Of the 275 patients with HK, 84 patients (30.55%) had recurrent HK twice and 62 patients (22.55%) had recurrent HK≥ 3 times. Albumin, phosphorus and the growth rate of body weight in the recurrent HK group were significantly higher than that in the single HK group. Serum potassium levels ≥ 5.0, ≥ 5.5 and ≥ 6.0 mmol/L were significantly associated with the rates of MACEs and hospitalization, respectively. When HK was defined as serum potassium level ≥ 5.0, the odds ratio (OR) of MACEs in HK was 1.535 (95 % CI 1.017-2.318, p = 0.041), The adjusted OR increased progressively as the serum potassium level gradually increased, reaching 1.598(95 % CI 1.046-2.439, p=0.030 ) for ≥ 5.5mmol/L, and 1.823 ( 95 % CI 1.027-3.236, p=0.040 ) for ≥ 6.0mmol/L. Compared with the normal potassium group, the OR for hospitalization in serum potassium ≥5.0 group were 1.541 (95% CI 1.014-2.342, p=0.043) after adjustment, and the adjusted OR value increased to 1.887 (95% CI 1.187-2.537, p=0.007) and 2.083 (95% CI 1.039-4.177, p=0.039) when the serum potassium level was ≥5.5 mmol/L and ≥6.0 mmol/L. Conclusions Among MHD patients, the prevalence of pre-dialysis HK and its recurrence rate remained high. Elevated serum potassium levels were correlated with an augmented risk of MACEs and hospitalization in these patients. These research findings emphasized the crucial significance of implementing effective monitoring and management strategies to precisely control potassium levels in MHD patients.