LONG-TERM PROGNOSIS OF DIFFERENT FORMS OF CORONARY HEART-DISEASE - THE REYKJAVIK STUDY

Background. While coronary heart disease (CHD) is a serious and often fatal disease the prognosis is Variable and major effort has been inve sted in risk stratification. The purpose of this study was to examine the relation between long-term prognosis and risk factors in different clinical categories of CHD. Methods. A general population sample of 9 141 men, aged 34-79 at entry into the study was divided into six group s with respect to manifestations of CHD at entry: I. Symptomatic infar ction, II. Silent or unrecognized infarction,.III. Angina pectoris wit h ischaemic changes on EGG. IV. Angina without ischaemic changes. V. A ngina by Rose questionnaire but not confirmed by a physician. VI. No m anifestations of CHD. Results. The risk factor profile varied consider ably between the different categories and by life-table analysis marke d differences in survival were demonstrated between the groups. The ri sk factors maintained their detrimental effects on prognosis in the pr esence of CHD. Thus, age, serum total cholesterol, impaired glucose to lerance and smoking were found by Cox's regression to be statistically significant independent risk factors of CHD mortality among men havin g manifestations of CHD (groups I-V). Furthermore, the composite risk score, a measure of the overall risk factor exposures had marked effec t on the prognosis of the various CHD groups. When the comprehensive r isk factor score for both CHD mortality and all-cause mortality was ac counted for marked differences persisted in the long-term prognosis, c ompared to those without CHD the infarct groups had about a 7.6- and 3 .7-fold risk of dying from CHD and all causes respectively, Those with angina had from 2.5- to 3.2-fold risk of CHD mortality and 1.7- to 2. 2-fold risk of all-cause mortality depending on the subgroup of angina , again compared to those without manifestations of CHD. Conclusion. D ifferent categories of CHD had different risk factor profiles and the long-term prognosis resulted from a complex interplay between those fa ctors and the diagnostic category of CHD. The risk factors maintained their detrimental effects on prognosis in the presence of CHD and afte r accounting for the comprehensive risk factor score marked difference s persisted in the long-term prognosis, being worst for those having s uffered a myocardial infarction, either symptomatic or silent.