Low testosterone in men predicts impaired arterial elasticity and microyascular function

• Type of Material: Article
• Authors: Frank E Corrigan, Emory University; Ibhar Al Mheid, Emory University; Danny Eapen, Emory University; Salim S Hayek, Emory University; Salman Sher, Emory University; Gregory Martin, Emory University; Arshed Quyyumi, Emory University
• Language: English
• Date: 2015-09-01
• Publisher: ELSEVIER IRELAND LTD
• Publication Version: Author Accepted Manuscript (After Peer Review)
• Copyright Statement: © 2015 Elsevier Ireland Ltd. All rights reserved.
• License: Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International
• Final Published Version (URL): http://dx.doi.org/10.1016/j.ijcard.2015.05.065
• Title of Journal or Parent Work: INTERNATIONAL JOURNAL OF CARDIOLOGY
• Volume: 194
• Start Page: 94
• End Page: 99
• Grant/Funding Information: This study was supported by The Emory Predictive Health Institute, Woodruff Fund, and in part by National Institutes of Health Grants UL1RR025008 from the Clinical and Translational Science Award program and M01RR0039.
• Keywords: Arterial stiffness; SERUM TESTOSTERONE; REACTIVE HYPEREMIA; CARDIOVASCULAR EVENTS; Testosterone; NITRIC-OXIDE; FLOW-MEDIATED DILATION; Cardiac & Cardiovascular Systems; Science & Technology; ELDERLY-MEN; Reactive hyperemia index; Cardiovascular System & Cardiology; ENDOGENOUS TESTOSTERONE; ERECTILE DYSFUNCTION; ENDOTHELIAL FUNCTION; Life Sciences & Biomedicine; PROGNOSTIC VALUE

Abstract

Background A low testosterone level in men is associated with increased adiposity, insulin resistance, and dyslipidemia. Whether low testosterone level is associated with arterial stiffness and endothelial and microvascular dysfunction remains unknown and was investigated in this study. Methods Serum testosterone was measured in 237 healthy men aged 50 years (SD 12). Endothelial and microvascular function were assessed as brachial artery flow-mediated dilation (FMD) and digital reactive hyperemia index (RHI), respectively. Arterial stiffness was evaluated by tonometry-derived pulse wave velocity (PWV) and central augmentation index (AIX). Results Mean total testosterone level was 16.3 nmol/L (SD 6.11) and 25% of subjects had low levels (< 12.0 nmol/L). Testosterone level correlated positively with RHI (r = 0.24, p < 0.001) and inversely with AIX (r = - 0.14, p = 0.033) but not with FMD or PWV, indicating impaired microvascular hyperemia and arterial elasticity with lower testosterone levels. After multivariate adjustment for the Framingham Risk Score and weight, testosterone level remained an independent predictor of RHI and AIX (β = 0.23, - 0.13; p = 0.001, 0.04, respectively). Conclusion In men with few co-morbidities, lower serum testosterone level is associated with microvascular dysfunction and increased pulse wave reflections, mechanisms by which lower testosterone levels may confer increased cardiovascular risk. Whether normalization of low testosterone level improves vascular function needs further investigation.