Improvement in Frailty is Associated with Improved Disability in Lung Transplantation

Frailty is associated with disability and poor health-related quality of life in lung transplant (LT) candidates. We tested whether frailty is independently associated with disability after LT. From 2/2010 to 9/2015, subjects were administered frailty and disability assessments before and at 3, 6, and 12 months post-transplant. We assessed frailty with the Short Performance Physical Battery (SPPB, range 0-12, lower scores denote increased frailty, Minimally Clinically Important Difference [MCID] =1). We assessed patient-reported disability with the Lung Transplant-Valued Life Activities (LT-VLA) scale (range 0-3; higher scores denote worse disability; MCID =0.3]). Using separate linear mixed models taking into account multiple observations and controlling for age, gender, and diagnosis, we estimated the impact of decreased SPPB (scaled to one point); an increase in FEV1 (scaled to 0.2L); and an increase in six minute walk distance (6MWD; scaled to 50m) on disability. We then combined all three independent variables plus covariates into a multivariate analysis. In 161 subjects, a 1-point improvement in SPPB was associated with a 0.11 improvement in LT-VLA disability (-0.11; 95% CI: -0.13 to -0.08) (Table). This association was larger than that observed for 6MWD (-0.08, 95% CI: -0.10 to -0.05). Change in FEV1 was not associated with disability (-0.01, 95% CI: -0.03 to 0.01). In multivariate analysis, the association between SPPB and disability was not substantively changed (-0.09; 95% CI: -0.12 to -0.06; p<0.05), whereas the association between 6MWD and disability was attenuated but still significant (-0.03, 95% CI: -0.05 to -0.01; p<0.05). FEV1 remained unassociated with disability. In this prospective study, improvement in frailty is associated with reduced disability after lung transplantation, taking into account exercise capacity and allograft function. Interventions aimed at improving disability in lung transplant recipients should take frailty into account.