Family Risk of Metabolic Disorder; A Parameter for Timely Screening of Vascular Endothelial Health

Abstract

Aim: To study the correlation of vascular endothelial health with family risk of metabolic disorders, in healthy overweight, obese and non obese subjects. Study Design: A case-control (pilot) study. Place and Duration of Study: The study was conducted in Cardiovascular Physiology lab, Department of Physiology, K.G.M.U Methods: Cases and controls comprised from January 2009 to February 2010. of 30 overweight / obese healthy subjects (BMI >= 25 kg/m2 and/or WHR (female>0.85; male>1) and 30 non-obese healthy subjects respectively (BMI< 25 kg/m2 and/or WHR (female<0.85; male<1) excluding subjects with secondary cause of abnormal blood flow. Vascular endothelial health was assessed via reactive hyperemic response measured via impedance plethysmography in the subject’s forearm. Fasting plasma glucose and serum lipid profile was also done. Results: On comparison of biochemical variables, lipid derangement was recorded in both the groups. Significant difference in VLDL (control 21.84±9.68, case 29.01±16.83) (p=0.048) and TG (control 101.22±-43.33; case145.21±84.02) (p=0.013), could be seen. VLDL & TG was deranged in 15 (6 cases + 9 controls) (P=0.371) and 14 (5 cases + 9 controls) (P=0.222) subjects respectively with no inter-group significant statistical difference. Inter-group reactive hyperemia at 1, 2, 3, 5, 7, 9 min post occlusion time showed no significant difference. Peak hyperemic response was seen at 2 minutes in both the groups. Though independent family history in first degree relatives of diabetes, coronary artery disease and/or hypertension showed a significant association with % RH at 2 min. (P =0.049), yet in group wise exploration, no significant association was seen. Conclusion: Adverse anthropometry is universally not associated with deranged lipid profile and vice versa. Raised RH response associated with positive family risk could be either due to hyperinsulinemia and/or some yet undeciphered cause but not solely as add-on sequelae of deranged anthropometry (BMI & WHR). In the light of our findings, we conclude that what seems as a favourable response i.e. a raised hyperemic response in subjects with a positive family history of risk factors, may be last ditch escape response before the vascular system succumbs to the inflammatory insult. Some yet undeciphered causes could thus be suspected of an adverse outcome and thus accordingly timely modified by lifestyle modifications or pharmacological interventions.