Prevalence of Abnormal Myocardial Perfusion SPECT Imaging and All Cause Mortality, among Asymptomatic Diabetic and Non-diabetic Blacks and Hispanics in an Inner-city Hospital

摘要

Diabetes is a Coronary Artery Disease (CAD) equivalent. Diabetics have extensive CAD, frequent silent ischemia and myocardial infarctions. Mortality in asymtomatic diabetics unergoing SPECT Tc99m-MIBI Myocardial Perfusion Imaging (MPI) is unknown. Performing MPI in asymptomatic diabetics may identify higher proportions of silent CAD. Revirwed 231 MPIs of asymptomatic diabetics (N=75) and non-diabetics (N=156), in Blacks and Hispanics who were referred for evaluation of CAD with no H/O CAD, PAD, MI, angina pectoris, revascularization,cardiomyopathy and valvular heart disease. All-cause mortality from Social Security Death Index was searched, giving at least 36 months of follow up. Diabetics were significantly older, more hypertensives and less likely to be smokers but there were no differences with regards to gender, postmenopausal status, hyperlipedimia, obesity, F/H/O premature CAD, occurrence of chest pain at peak stress and stress EKG abnormalities. Proportion of abnormal MPIs (ischemia only, scar only, ischemia and scar only, separately or all combined together) among both were similar (20%). Gated EF% was significantly lower among diabetics (47.5?18.4 vs. 53.8?14.4, p=0.009). Diabetics had significantaly higher all-cause mortality (25.65 vs. 5.7%, p=0.0002). On multivariate logistic regression analysis only diabetes (OR=7.45) and age (OR=1.05) were significant predictors of mortality. Asymptomatic diabetics compared to non-diabetics had lower EF, similar prevalence of abnormal stress EKG and MPI. However, all-cause mortaliy among diabetics was four fold higher compared to non-diabetics. Our findings suggest that all diabetics still be treated with aggressive risk factor modification, irrespective of their MPI results, to prevent the development and progression of CAD and reduce mortality.