Prevalence and RIsk factors for Silent Myocardial ischemia (PRISM): A clinico observational study in patients of type 2 diabetes

Abstract

Objectives: To estimate the prevalence and to identify potential risk factors of silent myocardial ischemia in a cohort of patients with asymptomatic type 2 Diabetes (diabetes) for early detection of coronary risk by employing objective noninvasive clinical screening tools for Subclinical Atherosclerosis. Methods: The study is a clinic-based observational study on 338 consecutive diabetes patients attending an urban health center from Eastern India. The response rate was 96.57% out of 350 eligible subjects, comprising 176 (52.1%) males and 162 (47.9%) females. Clinical, anthropometric, biochemical parameters were collected in all participants. Both tools, i.e., treadmill test (TMT) to identify subjects with silent myocardial ischemia, and carotid imaging to detect subclinical atherosclerosis by evaluating carotid intima-media thickness (CIMT), were assessed. Significant determinants were predicted by multivariable logistic regression. Results: The study group was divided into a TMT negative (n = 260), and a TMT positive group (n = 78). These 78 TMT positive subjects (23.1%) were identified to have silent myocardial ischemia. The prevalence of silent myocardial ischemia was more common in males (28.4%) than in females (17.3%). The mean CIMT in our study group was 0.6741 ± 0.034 mm (males - 0.684 ± 0.034 mm and females - 0.663 ± 0.032 mm). Age ≥50 years, CIMT ≥0.70 mm, hypercholesterolemia, and hypertriglyceridemia were significant determinants for identifying asymptomatic diabetics at risk for silent myocardial ischemia. Conclusion: Silent myocardial ischemia is highly prevalent at about one in four asymptomatic diabetic patients. An increased CIMT can be a surrogate marker of higher coronary risk amongst these asymptomatic diabetics.