Impaired renal function is associated with adverse outcomes in patients with chest pain discharged from internal medicine wards

Background: Assessment of chest pain is one of the most common reasons for hospital admissions in internal medicine wards. However, little is known regarding predictors for poor prognosis in patients discharged from internal medicine wards after acute coronary syndrome (ACS) rule-out. Objective: To assess the association of kidney function with mortality and hospital admissions due to ACS in patients with chest pain who were discharged from internal medicine wards following ACS rule-out. Methods: Included were patients admitted to an internal medicine ward who were subsequently discharged following an ACSrule-out during 2010–2016. The primary endpoint was the composite of all-cause mortality and hospital admission due to ACS at 30-days following hospital discharge. Results: Included in the study were12,337 patients who were divided into 3 groups according to renal function. Considering patients with an eGFR ≥ 60 ml/min/1.73m² as the reference group yielded adjusted hazard ratios for the composite of 30-day all-cause mortality and hospital admission for ACS that increased with reduced eGFR (HR = 2, 95%CI = 1.3–3.3, HR = 4.8, 95%CI = 3–7.6, for patients with eGFR of 45 to 59.9 or <45 ml/min/1.73m², respectively, p < 0.001). Similarly, reduced renal function was associated with increased 1-year all-cause mortality (HR = 1.6, 95%CI = 1.2–2.2, HR = 4.5, 95%CI = 3.4–5.9, for patients with eGFR of 45–59.9 or <45 ml/min/1.73m², respectively, p < 0.001). Conclusion: We found an independent graded association between lower eGFR and the risk of death and ACS among patients with chest pain who were discharged from internal medicine wards following an ACS rule-out. The eGFR may be combined in the risk stratification of patients with chest pain.