Coronary microvascular dysfunction in gestational diabetes: insights on possible mechanism from a large institutional...

Area of Science:

• Cardiology
• Endocrinology
• Metabolic Disorders

Background:

• Gestational diabetes mellitus (GDM) is a significant risk factor for developing coronary artery disease (CAD) and cardiovascular complications later in life.
• Coronary microvascular dysfunction (CMD) is a recognized precursor to CAD, and its prevalence is high in GDM patients, though underlying mechanisms require elucidation.
• Understanding the relationship between GDM, CMD, and metabolic biomarkers is crucial for early risk stratification and intervention.

Purpose of the Study:

• To investigate the associations between coronary flow reserve (CFR), a measure of coronary microvascular function, and key biomarkers related to hyperglycemia, insulin resistance, inflammation, and oxidative stress in women with a history of GDM.
• To identify specific biomarkers that predict the presence of coronary microvascular dysfunction in this patient population.

Main Methods:

• Noninvasive measurement of coronary flow reserve (CFR) using echocardiography in patients with a history of GDM.
• Assessment of common biomarkers including HbA1c (glycated hemoglobin), HOMA-IR (homeostatic model assessment of insulin resistance), triglyceride-glucose index, uric acid, and lipid profiles.
• Statistical analyses including univariate and multivariate linear regression models to determine the relationship between CFR and the measured biomarkers.

Main Results:

• Patients with reduced CFR (≤2.5) exhibited significantly higher levels of HbA1c, HOMA-IR, triglyceride-glucose index, uric acid, and total and non-HDL cholesterol compared to those with normal CFR (>2.5).
• Univariate analysis revealed strong associations between CFR and HbA1c (r=-0.32, p<0.001) and uric acid (r=-0.29, p<0.001), with moderate evidence for HOMA-IR (r=-0.21, p=0.006).
• A final regression model identified HbA1c (β=-0.31, p<0.001), HOMA-IR (β=-0.25, p=0.001), uric acid (β=-0.19, p=0.007), and waist circumference (β=0.25, p<0.001) as independent predictors of CFR.

Conclusions:

• Higher HbA1c, insulin resistance (HOMA-IR), and hyperuricemia in GDM patients are associated with an increased risk of coronary microvascular dysfunction.
• While these biomarkers contribute to predicting CMD, a significant portion of CFR variance remains unexplained, suggesting other factors, potentially transient hyperglycemia during pregnancy, play a role.
• These findings highlight the importance of monitoring cardiovascular risk factors in women with a history of GDM and underscore the need for further research into the pathogenesis of GDM-related cardiovascular complications.