Atheroma Progression and Vulnerability Under Continuous Glucose Monitoring

Overview

The OPTIMAL is a single-center, randomized trial to evaluate the efficacy of CGM-based glycemic control on atheroma progression in T2DM patients with CAD by using serial intravascular ultrasound (IVUS) and near-infrared spectroscopy (NIRS) imaging. A total of 90 eligible subjects will be randomized 1:1 into 2 groups to receive either CGM-based glycemic control or HbA1c-baded glycemic management. Coronary angiography and NIRS/IVUS imaging is repeated at the end of the assigned treatment period. Results: The primary endpoint is the normalized absolute change in total atheroma volume from baseline to 12 months. The secondary endpoints include (1) the absolute change in percent atheroma volume, (2) the percent change in lipid core burden index, (3) the change in coefficient variance measured by CGM, (4) the change in atherogenic markers (high-density lipoprotein functionality, proprotein convertase subxilisin/kexin type 9 and fatty-acid binding proteins), and (5) the frequency of hypoglycemia. Safety will also be evaluated.

Enrollment of 90 patients is planned at National Cerebral \& Cardiovascular Center in Japan. Study participants are randomly assigned to either CGM-based glucose management or HbA1c-based glucose management. Eligible subjects should have CAD requiring elective PCI. HbA1c at screening should be between 7.0 and 10.0%. Non-culprit vessel with its severe tortuousty and/or calcification will be excluded. Subjects with baseline estimated glomerular filtration rate \<40 mL/min/1.73m2 will not be eligible. After informed consent has been obtained, elective PCI will be conducted to treat culprit lesion. NIRS/IVUS imaging will be conducted to evaluate coronary atheroma. In the CGM-based glucose management group, CGM (FreeStyle Libre Pro®, Abbott, Chicago, Illinoi, the United States) and HbA1c measurement will be undertaken at baseline and 3, 6, 9 and 12 months following PCI. In the HbA1c-based glucose management group, HbA1c will be measured at baseline and 3, 6, 9 and 12 months after PCI, and CGM will be used at baseline and 12 months in a similar fashion.. With regard to the use of anti-diabetic drugs, in the CGM-guided glycemic control group, endocrinologist will select glucose lowering drugs to fulfill the following CGM-derived goals: (a) the frequency of hypoglycemia=0%, (b) the coefficient of variation \<36% and (c) averaged glucose level between 70-180 mg/dl.6 If the frequency of hypoglycemia is over 10% and/or the averaged glucose level is more than 400 mg/dl, patients will be asked to visit within 1 month after CGM measurement. In the HbA1c-guided therapy group, the selection of glucose lowering agents will be made according to the discretion of each endocrinologist to achieve HbA1c \<7.0%. At 12 months following PCI, patients will be hospitalized to take follow-up coronary angiography and intravascular imaging study. NIRS/IVUS imaging in the non-culprit vessel will be conducted again in a similar fashion.