Decreased Baroreceptor Refl ex Sensitivity in First-degree Relatives of Type 2 Diabetics is Linked to Sympathovagal Imbalance and Cardiovascular Risks

Abstract

Background: Though decreased baroreceptor refl ex sensitivity (BRS) promotes cardiovascular (CV) morbidity and CV risks are reported in the fi rst-degree relatives (FDR) of Type 2 diabetics, the pathophysiological mechanisms contributing to CV risks in these subjects are not yet elucidated. Methods and Results: Body mass index (BMI), CV parameters such as heart rate (HR), blood pressure (BP), rate-pressure product (RPP), stroke volume (SV), left-ventricular ejection time (LVET), cardiac output, total peripheral resistance (TPR) and BRS, spectral-indices of heart rate variability (HRV), autonomic function tests (AFT) and fasting blood glucose (FBG) were measured and analyzed in subjects of the study group (FDR of Type 2 diabetics, n = 79) and control group (subjects with no family history of diabetes, n = 115). BMI, HR, BP, RPP, SV, LVET, cardiac output, TPR, low-frequency to the high-frequency ratio (ratio of LF-HF power of HRV) and FBG were increased (P Conclusion: Decreased BRS in FDR of Type 2 diabetics predisposes them to CV dysfunction. BRS is linked to SVI and CV risks in these high-risk subjects. Key words: Autonomic derangement, baroreceptor refl ex sensitivity, cardiovascular risk, fi rst-degree relatives of Type 2 diabetics, heart rate variability, sympathovagal imbalance.