Pulmonary function is associated with frailty, hospitalization and mortality in older people: 5-year follow-up: Pulmonary function as a predictor of frailty

Background: The relationship between pulmonary impairment and frailty has rarely been studied in community-dwelling older adults. Objective: This study aimed to analyze the association between pulmonary function and frailty (prevalent and incident), identifying the best cut-off points to detect frailty and its association with hospitalization and mortality. Methods: A longitudinal observational cohort study with 1188 community-dwelling older adults was taken from the Toledo Study for Healthy Aging. The forced expiratory volume in the first second (FEV₁) and the forced vital capacity (FVC) were measured with spirometry. Frailty was evaluated using the Frailty Phenotype and Frailty Trait Scale 5. Associations between pulmonary function and frailty, hospitalization and mortality in a 5-year follow-up and the best cut-off points for FEV₁ and FVC were analyzed. Results: FEV₁ and FVC were associated with frailty prevalence (OR from 0.25 to 0.60), incidence (OR from 0.26 to 0.53), and hospitalization and mortality (HR from 0.35 to 0.85). The cut-off points of pulmonary function identified in this study: FEV1 (≤1.805 L for male and ≤1.165 L for female) and FVC (≤2.385 L for male and ≤1.585 L for female) were associated with incident frailty (OR: 1.71–4.06), hospitalization (HR: 1.03–1.57) and mortality (HR: 2.64–5.17) in individuals with and without respiratory diseases (P < 0.05 for all). Conclusion: Pulmonary function was inversely associated with the risk of frailty, hospitalization and mortality in community-dwelling older adults. The cut-off points for FEV₁ and FVC to detect frailty were highly associated with hospitalization and mortality in the 5-year follow-up, regardless of the existence of pulmonary diseases.