['To evaluate the association between components of metabolic syndrome (MS) and ischemic heart disease (IHD) in Taiwanese patients with type 2 diabetes mellitus (T2DM).', 'A total of 1,296 (604 men and 692 women) subjects with T2DM aged 62.5+/-11.7 (14-87) years were studied. MS was defined using the World Health Organization modified criteria and included more than 2 of hypertension, obesity, dyslipidemia and microalbuminuria. IHD was diagnosed through history or ischemic electrocardiogram according to the Minnesota codes. Results showed that MS was present in 76.2% and IHD in 36.3% of the patients, respectively. MS increased with age for both sexes, but there was no difference between men and women in the age groups of <45, 45-54 and 55-64 years. However, the prevalence of MS was significantly higher in women (87.7% vs 78.0%) in the age group>or=65 years. IHD prevalence was significantly higher in patients with MS, hypertension, dyslipidemia and obesity (p<0.01), and was higher with borderline significance for microalbuminuria (0.05<p<0.1). The respective age-adjusted odds ratios were 3.61 (2.57-5.08), 7.10 (5.38-9.38), 1.70 (1.32-2.18), 1.75 (1.33-2.28), and 1.11 (0.88-1.41).'] Is hypertension the most important component of metabolic syndrome in the association with ischemic heart disease in Taiwanese type 2 diabetic patients?