Association of Serum Potassium Levels with Mortality and Cardiovascular Events: Findings from the Chinese Multi-provincial Cohort Study

Abstract

Background: Dyskalemia involves critical electrolyte abnormalities and increases mortality risk in patients with acute clinical conditions. However, the association between dyskalemia and adverse outcomes in the general population is less well established. Objective: To investigate the association of serum potassium levels with mortality and cardiovascular events in the general population and to explore the characteristics of individuals at high risk. Design: A prospective cohort study. Participants: A total of 5220 participants aged 50–79 years in the Chinese Multi-provincial Cohort Study. Main Measures: Serum potassium levels were measured by the ion-selective electrode method. The outcomes were incident cardiovascular disease (CVD), CVD death, non-CVD death, and total death. Key Results: Of the 5220 participants, 48.2% were men, and the mean age was 62.3 (SD 7.6) years. Hyperkalemia was found in 8.7% of the participants and was significantly associated with total death (hazard ratio [HR], 1.62; 95% confidence interval [CI], 1.18–2.23) and CVD death (HR, 2.12; 95% CI, 1.25–3.61) after adjustment. Furthermore, the HRs (95% CIs) of hyperkalemia combined with 2 and ≥ 3 risk factors were 2.37 (1.50–3.74) and 4.06 (2.37–6.95) for total death and 3.26 (1.56–6.80) and 8.42 (4.06–17.50) for CVD death, respectively. The 10-year cumulative incidence of total death was 17.4% for participants with 2 or more risk factors. Conclusion: Hyperkalemia is associated with an increased risk of all-cause and CVD death, and this risk is more pronounced in patients with multiple risk factors. Our findings suggest that early identification and management of hyperkalemia in the general population are warranted.