Silent Myocardial Ischemia in Type 2 Diabetic Patients Asymptomatic For Coronary Artery Disease: A Cross- Sectional Study

Abstract

Background Coronary Artery Disease (CAD) is a common cause of premature morbidity and mortality in diabetics and is often asymptomatic because of silent myocardial ischemia (SMI). Early detection of SMI may prevent catastrophic cardiac events. Objective To study the prevalence of SMI in patients of type 2 diabetes mellitus (Type 2 DM), asymptomatic for CAD and to assess the role of conventional CAD risk factors in diabetic patients asymptomatic for CAD in the development of SMI. Methodology 102 cases of Type 2 DM without any clinical and electrocardiographic evidence of CAD, who attended a tertiary care hospital in North Delhi, over a period of one year, were studied for the present cross-sectional study. Detailed history, general physical examination, BMI, systemic examination and investigations like glycosylated hemoglobin (HbA1c), lipid profile, resting 12-leads electrocardiography (ECG) and treadmill test (TMT) were carried out. Results Out of 102 patients, TMT was found positive in 23 patients. It was positive in 12% among diabetic patients with duration of diabetes ≤5 years, 14.8% in patients with duration 6-10 years, 37.5% in patients with duration 10-15 years and 77.7% in patients with duration 16-20 years, respectively with p<0.001. Conclusion The prevalence of SMI in asymptomatic Type 2 DM without history of CAD is 22.54%. Duration of diabetes, presence of autonomic neuropathy (AN), dyslipidemia and HbA1c level are strong clinical predictors of SMI in asymptomatic Type 2 DM. Keywords: Silent myocardial ischemia; Type 2 Diabetes mellitus; Coronary artery Disease; Treadmill test Asymptomatic; Autonomic Neuropathy.