JAPI • VOL. 51 • APRIL 2003 355 * Senior Resident; ** Attending Cardiologist; *** Junior Consultant; **** Senior Consultant and Head, Non-Invasive Cardiology, Escorts Heart Institute and Research Centre, New Delhi. Received : 3.12.2002; Accepted : 17.2.2003 Original Article Endothelium-Dependent Brachial Artery Flow Mediated Vasodilatation in Patients with Diabetes Mellitus With and Without Coronary Artery Disease K Bhargava,* G Hansa,** M Bansal,* S Tandon,*** RR Kasliwal**** Abstract Aim of the Study : Endothelial function as assessed by brachial artery flow mediated vasodilatation (FMD) has been shown to be impaired in patients with coronary artery disease (CAD). Since diabetes mellitus (DM) has been considered to be CAD risk-equivalent, we sought to determine whether endothelial dysfunction is present in patients with DM independent of presence of CAD. Methodology : One hundred and ninety eight individuals were included in the study and divided into four groups: Group 1 - patients with risk factors for CAD, but no DM or CAD; Group 2 - patients with DM but no CAD; Group 3 - patients with CAD but no DM and Group 4 - patients with both DM and CAD. Brachial artery FMD assessment was performed once in all subjects and FMD was calculated as percentage increase in brachial artery diameter in response to increase in brachial artery flow. Results : Mean FMD was significantly higher in Group 1 (7.03 ± 2.87%) compared to the other three groups. Mean FMD in Group 2 (5.51 ± 2.12%) was similar to that in Group 3 (4.56 ± 2.70%; p value 0.195) but significantly higher than that in Group 4 (4.26 ± 1.93%; p value 0.038). There was no statistically significant difference in mean FMD in Group 3 and Group 4 (p value 0.65). Conclusion : Endothelial function as assessed by FMD is significantly impaired in diabetics compared to non-diabetics in absence of CAD. In addition, similar degree of impairment in endothelial function is seen in diabetics without CAD and non-diabetic patients having CAD, implying CAD risk-equivalence of diabetes. FMD, 6 thus standardizing the test for wider application. Several studies have demonstrated endothelial dysfunction not only in patients with established coronary artery disease (CAD), 7,8 but also in patients with cardiovascular risk factors including diabetes mellitus (DM). 2,9-12 Since diabetes is now considered to be ‘CAD’ risk equivalent, 13 we aimed to determine whether similar degree of impairment of endothelial function occurs in patients with DM and CAD that may be responsible for this ‘risk equivalence’. METHODS One hundred and ninety eight individuals were included in the study and divided into four groups. Groups 1 (n = 67) included subjects with risk factors for CAD, but no DM or CAD; Group 2 (n = 38) included patients with DM but no CAD; Group 3 (n = 58) included patients with CAD but no DM; and Group 4 (n = 35) included patients having both CAD and DM. Subjects in Group 1 and 2 were randomly selected from patients attending cardiology OPD of the Institute for routine checkup with no symptoms or signs of CAD. A negative treadmill test was used to confirm the INTRODUCTION E ndothelial dysfunction is a key early event in atherogenesis and is known to appear long before the formation of structural atherosclerotic changes. 1,2 Assessment of endothelial function, thus, can provide valuable insight into pre-intrusive phase of atherosclerosis and can be used an early marker of future atherosclerotic disease. However, invasive nature of the earlier available tests for endothelial function assessment precluded their use in clinical practice. 3 Development of non-invasive method of endothelial function assessment by brachial artery flow mediated vasodilatation (FMD), as described by Celermajer, 4 provided an extremely useful tool for cardiovascular research and for clinical application. The test can be performed easily and has proven reproducibility. 5 International Task Force on Brachial Artery Reactivity has recently laid guidelines for performance of