Syncope and Collapse Are Associated with an Increased Risk of Cardiovascular Disease and Mortality in Patients Undergoing Dialysis

Objective: This study explored the impact of syncope and collapse (SC) on cardiovascular events and mortality in patients undergoing dialysis. Methods: Patients undergoing dialysis with SC (n = 3876) were selected as the study cohort and those without SC who were propensity score-matched at a 1:1 ratio were included as controls. Major adverse cardiovascular events (MACEs), including acute coronary syndrome (ACS), arrhythmia or cardiac arrest, stroke, and overall mortality, were evaluated and compared in both cohorts. Results: The mean follow-up periods until the occurrence of ACS, arrhythmia or cardiac arrest, stroke, and overall mortality in the SC cohort were 3.51 ± 2.90, 3.43 ± 2.93, 3.74 ± 2.97, and 3.76 ± 2.98 years, respectively. Compared with the patients without SC, those with SC had higher incidence rates of ACS (30.1 vs. 24.7 events/1000 people/year), arrhythmia or cardiac arrest (6.75 vs. 3.51 events/1000 people/year), and stroke (51.6 vs. 35.7 events/1000 people/year), with higher overall mortality (127.7 vs. 77.9 deaths/1000 people/year). The SC cohort also had higher risks for ACS, arrhythmia or cardiac arrest, stroke, and overall mortality (adjusted hazard ratios: 1.28 (95% confidence interval (CI) = 1.11–1.46), 2.05 (95% CI = 1.50–2.82), 1.48 (95% CI = 1.33–1.66), and 1.79 (95% CI = 1.67–1.92), respectively) than did the non-SC cohort. Conclusion: SC was significantly associated with cardiovascular events and overall mortality in the patients on dialysis. SC may serve as a prodrome for cardiovascular comorbidities, thereby assisting clinicians in identifying high-risk patients.