Elevated heart rate as sympathetic biomarker in human obesity br

Background and aim: The present study was aimed at determining whether and to what extent a specific heart rate (HR) cutoff value allows to identify in obeses a more pronounced level of adrenergic overdrive.Methods and results: In 86 obese subjects aged 44.7 +/- 0.9 (mean +/- SEM) years and in 45 heathy lean controls of similar age we evaluated muscle sympathetic nerve traffic (MSNA, microneurography) and venous plasma norepinephrine (NE, HPLC assay), subdividing the subjects in 3 different groups according to their resting clinic and 24-h HR values (<70, 70-79 and 80-89 beats/minute). MSNA and plasma NE values detected in the three obese groups were almost superimposable each other, no significant difference between groups being observed. A similar behavior was observed when HR values were assessed during the 24-h Holter monitoring. In the group as a whole no significant relationship was detected between MSNA, plasma NE and clinic HR, this being the case also when 24-h HR replaced clinic HR in the correlation analysis. In contrast lean controls displayed a progressive significant increase in MSNA values form the group with clinic (and 24 Holter) values below 70 beats/minute to the ones with HR values between 70 and 79 and above 80 beats/minute.Conclusions: In the obese state measurement of resting HR may allow to provide some general information on the functional status of the adrenergic cardiovascular drive. When the information required, however, are more subtle the sensitivity of the approach appears to be reduced and HR cannot be regarded as a faithful sympathetic biomarker.(c) 2022 The Italian Diabetes Society, the Italian Society for the Study of Atherosclerosis, the Italian Society of Human Nutrition and the Department of Clinical Medicine and Surgery, Federico II University. Published by Elsevier B.V. All rights reserved.

Automated summary

This study aimed to determine whether a specific heart rate can accurately identify the level of adrenergic overdrive in obese individuals. The results showed that resting heart rate may not accurately reflect the functional status of the adrenergic cardiovascular drive in obese individuals. In contrast, healthy lean controls displayed significant differences in sympathetic nerve activity based on heart rate values.