HbA1c Independently Predicts Declined Myocardial Perfusion Reserve Index in Patients With Coronary Microvascular Disease Using Stress Perfusion Cardiac Magnetic Resonance: an Observational Study

Abstract Background We investigated whether glycated haemoglobin A1c (HbA1c) could independently predict the decline in the myocardial perfusion reserve index (MPRI) in patients with coronary microvascular disease (CMD) by stress perfusion cardiac magnetic resonance (CMR).Methods From November 2019, 174 patients with ischemic symptoms but without obstructive coronary disease were screened. The MPRI was recorded in 88 patients who underwent stress perfusion CMR detection. Eighty patients with an MPRI of < 2.5 were included in the study. The patients were divided into two groups based on whether their MPRI was greater or less than 1.47. The effects of each index on the MPRI were analysed using bivariate correlation analysis, and the risk factors for CMD were explored using logistic regression analysis.ResultsA total of 80 patients with an MPRI of 1.69±0.79 were included (mean age 54.07 ± 11.06 years; 66.3% male). CMD patients with an MPRI of ≤1.47 were higher than those in the group with an MPRI of >1.47 in age (57.61±9.65 years vs. 51.74±11.41 years), presence of diabetes mellitus (45.5% vs. 21.3%), fasting blood glucose levels [6.33(5.16, 8.01) vs. 5.30(5.15, 6.56)], and HbA1c levels [6.30(5.70, 7.70) vs. 5.80(5.60, 6.50)], (P < 0.05). The MPRI was negatively correlated with HbA1c (r=-0.378, P=0.004). Logistic regression analysis showed that HbA1c (OR=2.336, 95% CI: 1.119-4.876, P=0.024) was an independent risk factor for decreased MPRI in all patients with CMD, especially in patients without diabetes (OR=19.953, 95% CI: 1.743-93.449, P=0.029), but not in patients with diabetes (OR=0.984, 95% CI: 0.265-3.658, P=0.981).ConclusionsHbA1c is an independent predictor of MPRI decline in CMD patients, notably in CMD patients without diabetes, but not for those with diabetes.Trial RegistrationThis clinical trial has been registered in the Chinese clinical Trial Registry with an identifier: ChiCTR1900025810.