ObjectivesTo verify the prevalence of frailty in patients hospitalized with acute exacerbation of COPD; to compare two frailty assessment methods: Edmonton Scale and the Fried Frailty Phenotype, and to associate frailty with functioning in these patients.MethodsPatients hospitalized due to an acute exacerbation of COPD were included. The assessment of pulmonary function, frailty, and functioning was performed. Frailty assessment was performed by the Edmonton Scale and Fried Frailty Phenotype. Individuals were classified into “frail,” “pre-frail” and “non-frail.” Functioning was evaluated by the one sit-to-stand test.ResultsThirty-five individuals were included (17 male, 69 ± 9 years; FEV1/FVC 47 ± 10%; FEV1 34 (24–52) % predicted). Participants scored 3 (3-4) points on the Edmonton Scale and 7 (5–9) points on the Fried Frailty Phenotype. According to the Fried model, 17% were considered prefrail and 83% frail and in the Edmonton scale, 20% were classified as nonfrail, 29% prefrail, and 51% frail. There was a positive moderate correlation between the two methods (r= 0.42;p=0.011); however, there was no agreement between them (p=0.20). This probably occurs because they assess the same construct, i.e., frailty; however, they are different in their components. There was a negative and moderate correlation between the Fried Frailty Phenotype and functioning (r= −0.43;p=0.009).ConclusionMost hospitalized individuals with exacerbated COPD with severe and very severe airflow limitation are frail and the assessment methods correlate, but there is no agreement. Additionally, there is association between frailty and functioning in this population.