Association of Prehypertension Status with Sympathovagal Imbalance in Young First‑Degree Relatives of Type 2 Diabetics in Indian Population is Linked to Body Mass Index

Abstract

Background and Aim: As reports indicate that autonomic imbalance and hypertension in first‑degree relatives (FDR) of type 2 diabetics predispose them to cardiovascular (CV) risks, in the present study, we have assessed contribution of body mass index (BMI) to sympathovagal imbalance (SVI) and prehypertension status in these patients. Methods: BMI, basal heart rate (BHR), blood pressure (BP), prehypertension status, rate pressure product (RPP), and spectral indices of heart rate variability (HRV) were reordered and analyzed in FDR of type 2 diabetics (Study group, n = 63) and in individuals with no family history of diabetes (Control group, n = 87). Results: BMI and low‑frequency‑high‑frequency (LF‑HF), the ratio of LF to HF power (LF‑HF ratio) of HRV, a sensitive marker of SVI was significantly increased (P < 0.001) in the study group compared to control group. The SVI in the study group was due to concomitant sympathetic activation (increased LF) and vagal inhibition (decreased HF). In the study group, BMI was significantly correlated with LF‑HF ratio, BHR, BP, and RPP. Multiple regression analysis demonstrated an independent contribution of BMI to prehypertension status and bivariate logistic regression revealed significant prediction of prehypertension status by LF‑HF and BMI in the study group. Conclusion: BMI is more in FDR of type 2 diabetics and SVI in the form of increased sympathetic and decreased parasympathetic activity is present in them. Increased resting heart rate, elevated prehypertension status, decreased HRV, and increased RPP in these participants make them vulnerable to CV risks. BMI in these participants could be the link between SVI, prehypertension, and CV risks.