Background: The aim of this study was to examine the prognostic value of several clinical characteristics on long-term mortality and causes of death after acute coronary syndrome.
Methods: The ABC-2 study is a prospective investigation comprising 557 patients with acute coronary syndrome. During hospitalization, 33 clinical variables, including demographics, cardiovascular risk factors, in-hospital characteristics, and blood components, were examined. “Acute models” were survival models containing the variables accrued within 72 h from admission, and “sub-acute models” contained data accrued over a 7-day period. Cox regression models were used for the survival analysis.
Results: The 12-year follow-up study revealed that 51.2% of the patients died (15.8% of the patients died from coronary artery disease and/or heart failure, 12.6% of the patients experienced sudden death, 8.3% of the patients died from other-cardiovascular diseases, and 14.5% of the patients died from non-cardiovascular causes. The following factors were independently associated with all-cause mortality in both the acute and sub-acute models: age, left ventricular ejection fraction (negative), body mass index (non-linear), previous myocardial infarction, diabetes mellitus, blood glucose (non-linear), Killip class>1, albumin/creatinine ratio, and pre-hospital time delay. The variables associated with coronary artery disease and/or heart failure included age, left ventricular ejection fraction (negative), body mass index (non-linear), previous myocardial infarction, Killip class>1, albumin/creatinine ratio, and pre-hospital time delay, while the variables associated with sudden death included age, hypertension (negative), uric acid, left ventricular ejection fraction (negative), and pre-hospital time delay, and those associated with other- cardiovascular causes included age, hypertension, and albumin/creatinine ratio. The only variable associated with non- cardiovascular mortality was age. The C-statistic of the predictive models was 0.86 for all-cause mortality, whereas the C-statistic ranged from 0.74 to 0.80 for cardiovascular causes.
Conclusions: The ABC-2 study revealed clinical predictors of long-term mortality after acute coronary syndrome that might help prognostication, patient education, and risk modification. Furthermore, the results showed that the modes of death are independently associated with different baseline clinical features.
Keywords: Acute coronary syndrome; Mortality; Risk prediction; Survival analysis