Relationship Between Digital Vascular Function Measured by EndoPAT® in elderlY Patients and Arterial Stiffness

Due to the aging of populations worldwide, we observe an increase of age-related diseases and loss of autonomy with consequent personal, social, medical and economic implications. The aging population is a target for geriatric medicine, necessitating the development of specific diagnostic and therapeutic approaches in order to estimate cardio vascular risk in these individuals.

It is thought that arterial stiffening and endothelial dysfunction are among the earliest vascular properties altered with the onset of cardiovascular disease. Moreover aging is characterized by progressive fragmentation and break down of the elastic components of the aortic media, which are partially replaced by highly cross-linked collagen leading to stiffening, dilation, and elongation of the aorta . A major underlying mechanism of these modifications is endothelial dysfunction due to high oxidative stress and low-grade inflammation. Reactive hyperemia index (RHI), a key outcome of peripheral arterial tonometry (PAT) has recently become a reliable tool to measure microvascular endothelial function. Some studies have recently demonstrated the interest to measure in elderly patients arterial stiffness parameters in order to prevent loss of autonomy. This cross sectional study aimed at demonstrating the link between arterial stiffness evaluated by pulse wave velocity and endothelial dysfunction evaluated by RHI to implement the tools of cardio vascular risk evaluation in a population of elderly patients referred in a geriatric day hospital.

This study is a cross sectional monocentric retrospective study in a geriatric day hospital population coming for frailty and cardio vascular evaluation : clinical data of 148 patients hospitalized from April 2018 to December 2019 (20 months) of the Measurement of the ARterial-Cardiac AGEing and prevention evaluation of FRailty (MARCAGE.FR) geriatric day hospital of Nancy were retrospectively analyzed. Eligible patients were those who had benefited from an EndoPAT® measurement and arterial stiffness evaluation and aged over 60 years. Exclusion criteria to analyze aortic pulse wave velocity was the presence of atrial fibrillation and for EndoPAT® a poor quality of the signal. 105 among these 148 patients were finally selected as they present EndoPAT® good signal (reviewed by two operators).

All subjects arrived in a fasting state at the geriatric day hospital where anthropometric, frailty evaluation, hemodynamic and transcutaneous measurements of aortic pulse wave velocity (AoPWV) were performed at rest. Some of them had a cerebral Magnetic resonance imaging (MRI) examination. Participants were requested not to smoke or drink tea or coffee for 30 minutes and to sit quietly for 10 minutes at least, before blood pressure and other hemodynamic parameters were measured. Individuals were considered hypertensive if they had systolic blood pressure (SBP) values \> 150 mm Hg and/or diastolic blood pressure (DBP) values \> 90 mm Hg or if they were previously diagnosed as hypertensive and treated with one or more antihypertensive drug.

Eligibility Criteria:
Inclusion Criteria :

* age over 60 years
* referred to a day hospital check up
* arterial stiffness evaluation
* peripheral Arterial Tonometry Evaluation

Exclusion Criteria:

* atrial fibrillation during examination
* poor quality of the signals