Microvascular angina (cardiological syndrome X) per se is not associated with hyperinsulinaemia or insulin resistance

Background Microvascular angina has been found to be associated with insuli n resistance. However, many factors known to affect insulin sensitivity wer e not excluded in patient selection. We aimed to evaluate whether microvasc ular angina is per se associated with insulin resistance. Materials and methods We performed a Frequently Sampled Intravenous Glucose Tolerance Test (0.33 g kg(-1) b.w.) in 10 normal weight and normotensive p atients with microvascular angina, with normal glucose tolerance and normal plasma lipids. Ten healthy subjects, comparable for age, sex, body mass in dex, blood pressure and plasma lipids, were used as control group. Results Fasting serum glucose (4.49 +/- 0.2 SEM vs. 4.52 +/- 0.13 mmol L-1, P = 0.9), insulin (39.46 +/- 3.68 SEM vs. 47.12 +/- 4.6 pmol L-1, P = 0.21 ) and C-peptide (0.56 +/- 0.05 SEM vs. 0.53 +/- 0.05 nmol L-1, P = 0.68) va lues, as well as estimated parameters of insulin secretion and hepatic insu lin extraction were similar in the two groups. Insulin sensitivity values ( median, range) were also similar in the patients and control subjects (5.76 (3.39-12.30) vs. 7.54 (3.68-13.89. 10(-4). min(-1)/(mu U/mL), P = 0.97). Conclusion Microvascular angina per se is not associated with hyperinsulina emia or insulin resistance when other confounding factors are excluded in p atient selection.