1028-65 The Clinical Significance of High Pain Tolerance in Individuals with Coronary Artery Disease

Although previous studies have shown that patients with silent myocardial ischemia tend to be less sensitive to somatic pain than individuals with symptomatic coronary disease, the clinical relevance of this association has not been examined prospectively. The tourniquet test. a previously validated indicator of somatic pain tolerance. was performed on 280 patients 2.7±1.4 months following an acute index coronary event – either myocardial infarction (MI, n=192) or unstable angina (n=88). Patients were then followed for a mean of 2 years. The relationship between pain tolerance (PT) and several clinical and ischemic test variables (including stress thallium scintigraphy–STS) was examined.VariableHigh PTLowPTMultivariate(n=121)(n=159)P valueAge (years)57±1061±90.005Female (%)1419NSDiabetes (%)1921NSPrior MI(%)3941NSPrior Angina (%)45610.01Ischemia on STS (%)45340.03Recurrent MI or Death (%)96NSMultivariate logistic regression analysis revealed that patients with high PT were more likely to be younger (odds ratio (OR)=1.5), to have no history of angina prior to the index event (OR=2.0), and to have ischemia on STS lOR=1.8) than low PT, patients. There was no difference in cardiac event rates (death or nonfatal MI) between the low and high PT groups.ConclusionPatients with a high PT appear to have an impaired anginal warning system. The high PT patients had less angina prior to the index coronary event. but more inducible ischemia after the coronary event