Asymtomatic diabetics do not have a higher prevalence of abnormal myocardial perfusion scans as compared to non-diabetics in Blacks and Hispanics

Abstract

Background: Diabetes is a CAD equivalent. Performing MPI SPECT Tc99m-MIBI in asymptomatic diabetics would identify higher proportions of silent CAD earlier and may translate into better prevention, healthcare and lower healthcare cost. Methods: Retrospective review of 231 MPIs of patients asymptomatic for CAD. Patients with H/O CAD, PAD, MI, angina pectoris, revascularization were excluded. MPIs interpreted by two independent cardiologists blinded to histories. Two groups, non-diabetics (156) and diabetics (75). Results: Blacks & Hispanics 95%.Diabetics were significantly older (66±11vs 62.5±13, p=0.045), more hypertensives (92% vs 67%, p=<0.00005)and less likely to be smokers (12% vs 23%, p=0.04)but there were no differences in gender, postmenopausal status, hyperlipedimia, obesity,F/H/O premature CAD,occurrence of chest pain at peak stress, stress EKG abnormalities and proportion of abnormal scans. However, SPECT gated EF% was significantly lower among diabetics. See table. Conclusions: First of its kind study in Blacks and Hispanics. Asymtomatic diabetics, despite having significantly lower EF and being older and more hypertensives had similar prevalence of abnormal stress EKG and MPIs as compared to non-diabetics. Routine screening of asymptomatic diabetics does not detect more CAD than among non-diabetics and may not be cost effective. A large scale, prospective, randomized study is warranted. MPI Findings Non-Diabetics N = 156 Diabetics N = 75 p value Normal 80% 80% 0.98 Ischemia only 10% 5% 0.14 Scar only 4% 7% 0.35 Scar and Ischemia 6% 8% 0.52 Gated EF% 53.8 ± 14.4 47.5 ± 18.4 0.009