To determine the relationship between metabolic syndrome (MS) and erectile dysfunction (ED) and to see which risk factors correlated the best with ED. Methods: Seventy-nine cardiology clinic outpatients with coronary artery disease (CAD) and lipid metabolism disorder were recruited. They were categorized as having MS, hypertension (blood pressure greater than 130/85 mmHg) and dyslipidemia. ED was classified based on International Index of Erectile Function scores. Patients were grouped into quartiles based on body mass index (BMI). Chi-square, Pearson's correlation and regression tests were used for statistical analysis. Results: The mean age of the patients was 56.6 years. ED was diagnosed in 59 (74.7 %) of the 79 patients. In the 38 patients with MS, all had ED. ED was not significantly correlated with cholesterol levels (P > 0.05), but was found often in patients who had both hypercholesterolemia and HT (P 0.05). Tweenty-two of the 23 patients who had BMI greater than 30 had ED, which was significantly more prevalent than that in those who had normal BMI (P 0.5). Conclusion: ED is present in a high percentage of patients with MS. Among multiple risk factors for ED, MS correlates the most highly. The next most important risk group is the patients with hypertension +hypercholestrolemia and obesity (BMI > 30)
