The Relationship Between COPD and Frailty: A Systematic Review and Meta-Analysis of Observational Studies

Background: Frailty is common in seniors and is characterized by diminished physiological reserves and increased vulnerability to stressors. Frailty can change the prognosis and treatment approach of several chronic diseases, including COPD. The association between frailty and COPD has never been systematically reviewed. Objectives: The goal of this study was to conduct a systematic review and meta-analysis assessing the association of COPD with frailty and pre-frailty. Methods: Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were used when reporting this review. We searched PubMed, Web of Science, and Embase from January 1, 2002, to October 6, 2017. The quality of the studies was evaluated by using the Newcastle Ottawa Scale. Two assessors independently rated each study: scores > 7 were considered a low risk of bias; 5 to 7, a moderate risk of bias; and < 5, a high risk of bias. Pooled estimates were obtained through random effect models and Mantel-Haenszel weighting. Homogeneity (I²) and publication bias were assessed. Results: A total of 27 studies were selected: 23 cross-sectional, three longitudinal, and one both. The pooled prevalence of pre-frailty in individuals with COPD was 56% (95% CI, 52-60; I² = 80.8%); it was 19% (95% CI, 14-24; I² = 94.4%) for frailty. Patients with COPD had a two-fold increased odds of frailty (pooled OR, 1.97 [95% CI, 1.53-2.53]; I² = 0.0%). Three longitudinal studies, presenting heterogeneous aims and methods, suggested a bidirectional association between COPD and frailty. Conclusions: Frailty and pre-frailty are common in individuals with COPD. Older subjects with COPD have a two-fold increased odds of frailty. These results may have clinical implications, as they identify the need to assess frailty in individuals with COPD and to further investigate any potential negative effects associated with the co-occurrence of these conditions. Longitudinal research that examines temporal associations between COPD and frailty are needed to further clarify this relationship and to assess if treatment of COPD may prevent the onset of frailty. Trial Registry: PROSPERO registration No.: 58302; URL: https://www.crd.york.ac.uk/prospero/