Purpose: Long term prognosis of IHD patients is unknown. The aims of this study are introducing our unique audit referral system and showing the long term prognosis of IHD patients with optimal second prevention therapy.
Methods: IHD patient registry was established in 2009 to connect cardiologists in the core hospitals and more than 200 general practitioners in Shizuoka city. To audit the treatment of general practitioners, we adopted a circulation type cooperative form. Target values of risk factors are as follows; low-density-lipoprotein cholesterol (LDL-C) concentration less than 100 mg/dl, HbA1c in diabetic patients less than 7%, systolic blood pressure (SBP) less than 130mmHg, and diastolic blood pressure (DBP) less than 80mmHg. General practitioners are required to introduce registered patients at least once a year even there is no event. Mean follow-up interval was 2001±794 days.
Results: We could follow 1240 patients who were registered from May 2009 to December 2013 and followed by at least one visit to the hospital in the prescribed manner until September 2018. Mean age was 77.3±10.6 years old, and 39.6% of them had old myocardial infarction. Latest risk factor controls are as follows; LDL-C 88.0±21.3mg/dl, HbA1c control in diabetic patients 7.0±1.1%, SBP and DBP 133.7±16.5 and 75.0±11.8mmHg respectively.
Cumulative incidence of all-cause death was 10.8%, cardiac death was 1.5%, and coronary event (combination of cardiac death, myocardial infarction, angina pectoris which need hospitalization, and any lesion revascularization) was 15.8%. Cumulative incidence of major bleeding was 2.6%. The patients were divided into three groups without overlapping; major bleeding group (n=34), coronary event group (n=195), and event-free group (n=1049). The nonparametric test showed significant differences between three groups concerning age (p=0.026), the rate of using antithrombotic drugs (p<0.001) and mortality (p=0.017). Kaplan-Meier method concerning all-cause death showed a significant difference between event-free group and major bleeding group (log rank p=0.002), and coronary event group and major bleeding group (p=0.026), while no statistical difference between event-free group and coronary event group.
Conclusions: Our unique referral system revealed long term events in the stable IHD patients in Japan. The major bleeding event is a strong predictor of long term mortality in IHD patients rather than the coronary event.