Correlation between Subclinical Left Ventricular Systolic Function and Diabetic Microvascular Complications in Patients with Type 2 Diabetes postprint

Abstract: Background  In recent years，studies have demonstrated the use of ultrasound speckle tracking techniques for the early evaluation of subclinical left ventricular（LV） systolic function in patients with type 2 diabetes mellitus（T2DM）. In addition，long-term exposure to hyperglycemia severely damages the microvascular system. However，the interaction between diabetic microvascular complications and subclinical LV systolic function has not been fully understood. Objective  To investigate the relationship between subclinical LV systolic function and diabetic microvascular complications in patients with T2DM. Methods  A total of 150 patients with T2DM who were admitted to the Department of Endocrinology，the First Affiliated Hospital of Air Force Medical University from June to December 2021 were selected in the cross-sectional study and all underwent conventional echocardiography，pulsed tissue Doppler echocardiography and two-dimensional speckle tracking echocardiography（2D STE）. The 2D global longitudinal strain（GLS） of LV was obtained to assess the subclinical LV systolic function. Diabetic microvascular complications were defined as combined diabetic retinopathy，diabetic kidney disease or peripheral neuropathy. The subjects were divided into the T2DM alone group（T2DM alone group，n=76），the T2DM with 1 complication group〔T2DM+C（1） group，n=37〕 and the T2DM with 2 to 3 complications group〔T2DM+C（2 to 3）group，n=37〕 according to the cumulative number of microvascular complications. The general demographic characteristics and biochemical indices of patients in the three groups were compared. The relationship between microvascular complications and subclinical LV systolic function was assessed by using Spearman correlation analysis and Logistic regression analysis. Results  GLS was lower in the T2DM+C（1） and T2DM+C（2 to 3） groups than in the T2DM alone group （P<0.05）. Spearman rank correlation analysis showed that the number of diabetic microvascular complications involved was negatively correlated with GLS（rs=-0.349，P<0.001）. Logistic regression analysis showed that after adjustment for multiple factors of gender，age，duration of diabetes，hypertension，glycosylated hemoglobin，fasting glucose，blood creatinine，heart rate，urinary microalbumin，and LV fraction shortening，GLS was decreased in the T2DM+C（1） group〔OR=0.744，95%CI（0.601，0.920）〕 and the T2DM+C（2 to 3） group〔OR=0.707，95%CI（0.525，0.952）〕 compared with the T2DM alone group （P<0.05）. Multivariable Logistic regression analysis based on hypertension stratification showed that after adjustment for the same confounding factors described above，diabetic microvascular complications remained independently associated with reduced GLS〔with hypertension：OR=0.556，95%CI（0.321，0.963）；without hypertension：OR=0.739，95%CI（0.558，0.979），P<0.05〕 in T2DM patients with or without hypertension. Conclusion  The LV systolic function may already be impaired in hospitalized T2DM patients with diabetic microangiopathy. The increased number of microvascular complications involved was closely related to subclinical LV systolic dysfunction，independently of hypertension.