Heart failure, frailty, and pre-frailty: A systematic review and meta-analysis of observational studies

Frailty is a syndrome characterized by reduced physiological reserves, increased vulnerability to stressors and adverse health outcomes. Frailty can change the prognosis and treatment approach of several chronic diseases, including heart failure (HF). The aim of this study was to conduct a systematic review and meta-analysis assessing the association of HF with frailty and pre-frailty. We employed PRISMA guidelines for reporting the results. We searched PubMed, Web of Science, and Embase from 01/01/2002 to 29/11/2019.The quality of the studies was evaluated with the Newcastle Ottawa Scale. Pooled estimates were obtained through random-effect models and Mantel-Haenszel weighting. Homogeneity (I²) and publication bias were assessed. We selected 54 studies (52 cross-sectional, one longitudinal, and one with both designs). The pooled prevalence of pre-frailty in individuals with HF was 46% (95% CI = 38-53; I² = 93.1%) and 40% (95% CI = 31-48; I² = 97%) for frailty. The proportion of pre-frail individuals with HF was 20% (95%CI = 15-25; I² = 99.2%) and the proportion of frail individuals with HF was 31% (95% CI = 17-45; I² = 98.7%). Two studies using the same frailty definition reported estimates for the association between frailty and HF (pooled OR = 3.44; 95% CI = 0.75-15.73; I² = 95.8%). In conclusion, frailty and pre-frailty are frequent in people with HF. Persons with HF have 3.4-fold increased odds of frailty. Longitudinal studies examining bidirectional pathophysiological pathways between HF and frailty are needed to further clarify this relationship and to assess if specific treatment for HF may prevent or delay the onset of frailty and vice versa.