BACKGROUND: In past years several risk factors have been associated with the incidence of coronary heart disease. The aim of this study was to investigate the associations between the risk of developing acute coronary syndromes and several risk factors in Greece. METHODS: During 2000-2002, 700 male (59 +/- 10 years old) and 148 female (65 +/- 9 years old) patients with the first event of an acute coronary syndrome were randomly selected from cardiological clinics of all Greek regions. Afterward, 1,078 population-based controls were randomly selected from the same hospitals and matched to the patients by sex and age. Detailed information regarding their medical and psychosocial status and various lifestyle habits related to coronary risk was recorded. RESULTS: The frequency ratio between males and females in the case series of patients was 4:1. The statistical analysis showed that smoking (odds ratio = 1.61, P < 0.001), hypertension (odds ratio = 1.99, P < 0.001), hypercholesterolemia (odds ratio = 3.53, P < 0.001), diabetes mellitus (odds ratio = 2.44, P < 0.01), family history of CHD (odds ratio = 3.19, P < 0.001), exposure to passive cigarette smoking (odds ratio = 1.54, P < 0.01), and depressive episodes (odds ratio = 1.35, P < 0.01) were associated with an increased coronary risk, while physical activity (odds ratio = 0.81, P = 0.01), adoption of Mediterranean diet (odds ratio = 0.80, P < 0.05), and high education (odds ratio = 0.81, P < 0.001) were associated with a significant reduction of the coronary risk. Also, a J-shape association was found between alcohol intake and coronary risk. CONCLUSION: Several emerging lifestyle risk factors (education, depression, diet, passive smoking), in addition to the conventional ones, may contribute to the risk of coronary events in this population.