Conventional and non-conventional coronary risk factors in male premature coronary artery disease patients already having a low Framingham risk score

Background - Individual risk factors and, more importantly, global risk assessment tools such as the Framingham risk score have been used successfully for risk prediction especially in older patients. However, there is paucity of data about the coronary heart disease prediction in premature coronary artery disease patients with a low Framingham risk score. Methods and results - We recruited 102 consecutive young patients without hypertension and diabetes mellitus in the study. All subjects had had chest pain and underwent coronary angiography since non-invasive diagnostic test results suggested ischaemia. Forty-five patients having at least one coronary lesion independent of severity were included in the study group. The remaining fifty-seven subjects without any coronary lesion were used as control group. Conventional and non-conventional risk factors were evaluated both in patients and control subjects. Framingham risk score and absolute 10-year hard CHD events risk were also calculated for each individual. The coronary heart disease group had a significantly higher smoking frequency as compared to the control group. They also had higher plasma levels of triglycerides, apolipoprotein B and apo B/A1 ratio but a smaller LDL particle size. We failed to find any independent CHD predictor after logistic regression analysis. However, individual ROC curve analysis of risk factors revealed that apolipoprotein B, triglycerides and apo B/A1 ratio have the highest area under the curve for coronary artery disease prediction. Conclusions - The Framingham risk score may underestimate the true risk of an individual. Incorporating non-conventional risk factors such as apolipoprotein B and apo B/apo A1 ratio may provide valuable information in these patients.