Cardiovascular regulation during active standing orthostatic stress in older adults living with frailty: a systematic review

Abstract

Background: Orthostatic hypotension (OH) is a relevant cardiovascular disorder associated with frailty and delayed cardiovascular regulatory responses, contributing to cardiovascular dysregulation. This dysregulation affects blood pressure (BP) control, increasing the risk of falls and mortality. This systematic review aimed to determine whether older adults living with frailty have impaired cardiovascular regulatory responses during active standing orthostatic stress.

Methods: MEDLINE (from 1946), PUBMED (from 1966), EMBASE (from 1974), CINAHL (from 1963), and SCOPUS (from 2004) were systematically searched for studies on cardiovascular regulation during active standing orthostatic stress in older adults living with frailty. The selection of studies involved the following criteria: ≥ 60 years, OH classification, continuous monitoring of beat-by-beat BP, active standing, and frailty status. The nine-point Newcastle-Ottawa Scale was used to assess the study quality.

Results: Of 7441 articles identified, 5 articles were included, but 3 independent data sets were extracted due to two studies reporting the same participants' cohort, resulting in an analysis of 726 participants (79±5 years, 41.7 % males). Frailty was associated with a greater drop in BP (-61 mmHg), blunted HR (Frail: 8 bpm; non-frail: 16 bpm), and longer recovery after active standing, occurring between 30-60 s instead of 0-30 s (healthy systems). OH prevalence ranged from 3 to 98 %, being higher in frail people.

Conclusions: Older adults living with frailty experience a greater drop in BP, a blunted HR response, and prolonged recovery time following active-standing orthostatic stress. This cardiovascular dysregulation contributes to the highest prevalence of OH among frail individuals.

Keywords: Blood pressure regulation; Heart rate; Orthostatic hypotension; Orthostatic intolerance; Postural transition.