Factors associated with 30-day mortality in patients with acute heart failure presenting to the emergency department: a retrospective cohort study

Abstract Background Acute heart failure is common in emergency departments, with medical technology promoting longer survival. Despite improvements in medical care, optimal criteria for discharge or admission decisions remain challenging to establish, particularly in resource-limited emergency department (ED) settings. Objective To identify factors associated with 30-day all-cause mortality in patients with acute heart failure. Methods This study was a retrospective cohort study conducted in Maharaj Nakorn Chiang Mai Hospital from 2011 to 2018. All patients diagnosed with acute de novo or decompensated heart failure and presenting to the ED were divided into two groups: those who died within 30 days and those who survived beyond 30 days. Factors obtained from medical history taking, physical examination, and laboratory results were compared between the two groups. Cox proportional hazards models were used to determine hazard ratios (HR) and 95% confidence intervals (95% CI). Results We analyzed 1,951 patients diagnosed with acute de novo or decompensated heart failure. The overall 30-day all-cause mortality rate was 11.0%. Multivariable analysis identified seven independent prognostic factors. Six factors were associated with increased 30-day all-cause mortality: respiratory rate >30 breaths/min; HR 1.61 (95% CI 1.03–2.53), systolic blood pressure 2 mg/dL; HR 1.61 (95% CI 1.08–2.39), serum sodium levels 5.0 mEq/L; HR 1.59 (95% CI 1.02–2.49), and the use of inotropic drugs; HR 2.89 (95% CI 1.50–5.56). Conversely, dyslipidemia was associated with lower 30-day all-cause mortality (HR 0.54, 95% CI 0.36–0.81). Conclusion Independent predictors of 30-day all-cause mortality included respiratory rate >30 breaths/min, SBP < 90 mmHg, creatinine >2 mg/dL, sodium 5.0 mEq/L, and inotrope use. These factors help identify high-risk patients requiring close monitoring and potential admission.