Objective: To identify the influencing factors of surviving time of patients with non-ST elevation acute coronary syndromes in China.
Methods: The data of patients with non-ST elevation acute coronary syndromes hospitalized in 38 hospitals in China, including clinical characteristics, therapeutic procedure, and major events at hospitalization and two years' follow-up period, were collected and analyzed as part of an international multicentre registry--OASIS. No particular intervention was needed in patients' therapy. The needed data were recorded by filling in the Case Report Forms offered by Canadian Cardiovascular Collaboration according to the protocol. Cox regression model was used to analyze the association with survival and multiple factors recorded.
Results: From April 1999 to December 2001, 2294 patients with non-ST elevation acute coronary syndromes were enrolled in 38 Chinese hospitals nationwide, two years' follow-up had been finished among 2188 of which with a mean age of 62.8 +/- 8.3 and 62.3% being male. The clinical diagnosis at admission was unstable angina in 88.5% of the patients and was non Q-wave myocardial infarction in the remaining 11.5%. The number of death totaled up to 174 with a mortality of 7.6% by the end of the two years' follow-up. The most common cause of death was severe arrhythmia or sudden death (92 cases, 52.9%). More than 70 factors had been analyzed by Cox regression model in order to determine which might influence survival. Risk factors that reduced lifetime were: frequencies of myocardial infarction during follow-up period, stroke during hospitalization, thrombolysis during hospitalization, frequencies of heart failure during follow-up period, heart failure during hospitalization, frequencies of stroke during follow-up period, history of myocardial infarction, times of hospitalization because of non-cardiovascular disease during follow-up period, history of diabetes mellitus, duration of the first hospitalization, and age by the first hospitalization. Protective factors that prolonged lifetime were the frequencies of using oral anticoagulant, anti-platelet medicine, nitrate, and lipid lowering agents during follow-up period.
Conclusion: The most common cause of death in patients with non-ST elevation acute coronary syndromes is severe arrhythmias or sudden death in China. Several factors influence the survival of patients. The effects of most factors in this study are similar to those founded by previous evidence based medical study.