Myocardial perfusion imaging for evaluation of suspected ischemia and its relationship with glycemic control in South African subjects with diabetes mellitus

Background: The relationship between myocardial perfusion imaging (MPI) abnormalities, diabetes mellitus, and glucose control in South African populations is unknown. It was hypothesized that in subjects undergoing MPI for suspected coronary artery disease (CAD), those with diabetes would have more extensive perfusion defects and that diabetes control would influence MPI abnormalities. The aim of this study was to examine the relationship between the severity of CAD diagnosed with MPI in subjects with and without diabetes and to determine the relationship between diabetes control and extent of CAD. Methods: This study was a retrospective chart review of 340 subjects in whom MPI scans were performed over a 12-month period. Results: Subjects with diabetes had a higher prevalence of abnormal MPI, with more extensive ischemia, compared with subjects without diabetes (85.6% versus 68%; odds ratio 2.81, P<0.01). Glycated hemoglobin $7.0% was associated with a higher risk of abnormal MPI, with more extensive ischemia, compared with subjects having diabetes and glycated hemoglobin <7.0% (odds ratio 2.46, P=0.03) and those without diabetes (odds ratio 4.55, P=0.0001). Conclusion: Subjects with diabetes have more extensive myocardial ischemia when compared with subjects without diabetes. Furthermore, poorer diabetes control is associated with more abnormalities on MPI scanning.