H. Schulte

BACKGROUND: The absolute risk of an acute coronary event depends on the totality of risk factors exhibited by an individual, the so-called global risk profile. Although several scoring schemes have been suggested to calculate this profile, many omit information on important variables such as family history of coronary heart disease or LDL cholesterol. METHODS AND RESULTS: Based on 325 acute coronary events occurring within 10 years of follow-up among 5389 men 35 to 65 years of age at recruitment into the Prospective Cardiovascular Münster (PROCAM) study, we developed a Cox proportional hazards model using the following 8 independent risk variables, ranked in order of importance: age, LDL cholesterol, smoking, HDL cholesterol, systolic blood pressure, family history of premature myocardial infarction, diabetes mellitus, and triglycerides. We then derived a simple point scoring system based on the beta-coefficients of this model. The accuracy of this point scoring scheme was comparable to coronary event prediction when the continuous variables themselves were used. The scoring system accurately predicted observed coronary events with an area under the receiver-operating characteristics curve of 82.4% compared with 82.9% for the Cox model with continuous variables. CONCLUSIONS: Our scoring system is a simple and accurate way of predicting global risk of myocardial infarction in clinical practice and will therefore allow more accurate targeting of preventive therapy.

Coronary thrombosis is regarded as the final occlusive event in the progress of coronary heart disease (CHD). Disturbances of the hemostatic system may favor this process and thus may indicate increased risk of myocardial infarction. Coagulation and lipid factors were measured in 2116 healthy male participants of the Prospective Cardiovascular Münster (PROCAM) study. After 6 years of follow-up, 82 coronary events (9 sudden cardiac deaths and 14 fatal and 59 nonfatal myocardial infarctions) were observed. The mean plasma fibrinogen levels of the event and nonevent groups differed by 0.25 g/L (2.88 [SD, 0.68] versus 2.63 [SD, 0.63] g/L, respectively; P = .001). The incidence of coronary events in the upper tertile of the plasma fibrinogen distribution was 2.4-fold higher than in the lower tertile. By multiple logistic function analysis, plasma fibrinogen was found to be an independent risk indicator for CHD (P < .05). Individuals in the high serum low-density lipoprotein (LDL) cholesterol tertile who also showed high plasma fibrinogen concentrations had a 6.1-fold increase in coronary risk. Unexpectedly, individuals with low plasma fibrinogen had a low incidence of coronary events even when serum LDL cholesterol was high. The mean factor VIIc activities in the event and nonevent groups did not differ significantly (112.3% [SD, 19.9] versus 108.4% [SD, 21.6]; P = .09). There was, however, a trend toward higher factor VIIc values when only fatal events were taken into account. Thus, higher levels of plasma fibrinogen markedly increased the predictive power of high serum LDL cholesterol. Low plasma fibrinogen is associated with low coronary risk even when LDL is raised.

We quantified lipoprotein(a) [Lp(a)] immunochemically in young (less than 46 y) male survivors of myocardial infarction and in age-matched controls recruited from participants of the Prospective Cardiovascular Münster (PROCAM) study. We further determined apolipoprotein E polymorphism and measured triglycerides, total cholesterol, high- and low-density lipoprotein cholesterol (HDL and LDL), and apolipoproteins AI, AII, and B in the serum of these subjects. Lp(a) concentrations in serum were not correlated with other well-recognized risk factors for early myocardial infarction such as apolipoproteins AI and B, LDL cholesterol, and HDL cholesterol. Apolipoprotein E polymorphism did not affect Lp(a) concentrations, but had a major influence on apolipoprotein B concentration. Lp(a) concentrations were not influenced by age. Our data suggest that (a) an increased concentration of Lp(a) constitutes an independent risk factor for early myocardial infarction and (b) the concentrations of Lp(a) and LDL cholesterol (apolipoprotein B) in serum are under separate metabolic control.