HP06: Baroreflex sensitivity is predictor of mortality in general elderly population

Abstract

Baroreflex sensitivity (BRS) is known to be a predictor of morbidity and mortality in metabolic and cardiovascular diseases. However, although we know that BRS decreases with age, we do not know whether BRS is predictive of mortality in general elderly population. The objective of this work is to study the predictive value of BRS in the mortality of an elderly population. We followed-up 1011 healthy elderly subjects (PROOF study, 68.4 ± 0.8 years, 609 women) during 19 years. At inclusion, we continuously recorded electrocardiogram, blood pressure, and respiration during 15 minutes insupine and upright position. BRS has been estimated using the sequence method. The mortality risk hazard ratio (HR) was calculated by comparing the first and the third terciles for BRS index, ajusted for sexe and cardiovascular risk factors. 207 subects passed away during the follow-up (20.5%) ; 74 from cardiovascular cause (7.3%). As results always show a sexe effect, men and women were analyzed separately. For women, HR were not statisticaly significant. For men, there was an increase of the risk when comparing BRS < 3.08 and BRS > 4.63 mmHg measured in upright position (HR 3.16 [1.32 – 3.54 ; p < 0.002]. Results were unsignificant for BRS measured in supine position. This study highlights that clinical value of BRS assessment could be usefull in general elderly population, more in men than in women. Moreover, BRS seems to be more informative when estimated in the upright position which is rarely the case for its recording in routine use.