Frail older adults are more likely to have autonomic dysfunction: A systematic review and meta-analysis

Autonomic dysfunction and frailty are two common and complex geriatric syndromes. Their prevalence increases with age and they have similar negative health outcomes. In PubMed and Web of Science we screened studies identifying a relationship between autonomic function (AF) and frailty in adults aged ≥ 65 years. Twenty-two studies of which two prospective and 20 cross-sectional were included (n = 8375). We performed a meta-analysis for the articles addressing orthostatic hypotension (OH). Frailty was associated with 1.6 higher odds of suffering from consensus OH (COH) {OR= 1.607 95%CI [1.15-2.24]; 7 studies; n = 3488}. When measured for each type of OH the largest trend was seen between initial OH (IOH) and frailty {OR= 3.08; 95%CI [1.50-6.36]; 2 studies; n = 497}. Fourteen studies reported other autonomic function alterations in frail older adults with 4-22% reduction in orthostatic heart rate increase, 6% reduction in systolic blood pressure recovery, 9-75% reduction in most common used heart rate variability (HRV) parameters. Frail older adults were more likely to have impaired AF. Diagnosis of frailty should promptly lead to orthostatic testing as OH implicates specific treatment modalities, which differ from frailty management. As IOH is most strongly correlated with frailty, continuous beat to beat blood pressure measurements should be performed when present at least until cut-off values for heart rate variability testing are defined.