Effekt eines dreiwöchigen pneumologischen Rehabilitationsprogramms auf den Frailty-Status bei Patient:innen vor Lungentransplantation - eine Beobachtungsstudie

Frailty is a clinical syndrome of decline in physical and cognitive function leading to a decreased reserve and resistance to stressors. In candidates for lung transplantation (LTx), frailty is present to a significant extend (10-45%) and is considered a risk factor for waiting list removal. There is also an association with increased one-year mortality after the procedure, which increases with higher levels of frailty. Therefore, the reduction of frailty may offer a possibility of optimizing the overall LTx success, which is not only of individual but also of social and economic interest due to the limited availability of or-gans and high costs to the healthcare system. The demonstated prospective observational study investigated the effects of an inpatient pulmonary rehabilitation (PR) on the frailty state of LTx candidates. 32 LTx candidates with an underlying disease of Chronic Obstructive Pulmonary Disease (COPD), Intersti-tial Lung Disease (ILD) or a mixed form (CPFE) were recruited while attending a specific three-week in-patient PR programme at Schön-Klinik Berchtesgadener Land between February and November 2019. As primary outcome we considered the change in score by Short Physical Performance Battery (SPPB, range 0-12; frail ≤7, prefrail: 8-9, non-frail ≥10) between the beginning and end of PR. As secondary outcome the change in score of Fried Frailty Phenotype (FFP, range 0-5; frail ≥3, prefrail: 1-2, non-frail: 0) was measured. The SPPB assesses physical performance through a balance test, a 4m gait speed test, and a Sit-to-Stand test. The FFP evaluates weight loss, daily activity, gait speed, grip strength and exhaustion. In addition, other physical, social, psychological and cognitive functions, as well as the subjects' exercise adherence during rehabilita-tion, were assessed and examined for potential correlations with their frailty state. Among the included 32 subjects [age: 59±5 yrs.; 53.1% female; 31% actively listed; 44% COPD, 44% ILD, 12% CPFE] there was a notable prevalence of frailty [SPPB:16%; FFP: 26%] and prefrailty [SPPB: 31%; FFP: 58%] at PR onset. 28 subjects showed a SPPB-Score<12 at baseline measurement and were therefore included in the analysis of the primary outcome. The average baseline SPPB-score of 8.8 points (median: 9, prefrail) was increased by a statistically significant and clinically relevant 1.4 points resulting in an average of 10.2 points (median: 11, non-frail) at the end of the rehabilitation programme (p<0.001). There was a significant reduction in peo-ple categorized as frail (from 5 to 3) and prefrail (from 10 to 4 participants), while the group being non-frail increased remarkably (from 13 to 21 participants). Almost all sub-jects improved by at least 1 point (MCID=1) apart from 4 participants (14.3%) whose score remained unchanged. No deterioration in score was observed. The average FFP-score of 1.9 points (median: 2, prefrail), which was additionally meas-ured in 27 subjects, also improved statistically significantly by 0.9 points to 1.0 points (median: 1, prefrail) during the course of the PR. Similar to the measurement by SPPB, the proportions of the groups frail (FFP≥3; from 8 to 4 persons) and prefrail (FFP=1-2; from 15 to 11) decreased during PR, while the non-frail group (FFP=0) presented an increase of 8 subjects. Apart from 10 candidates with unchanged FFP-score, 17 sub-jects improved by at least one point (MCID=1). Our multilateral approach to the topic showed that frailty has not only a physical impact on mobility and muscle strength, but also affects quality of life and mental health of LTx candidates. Particularly notable are the strong correlations found between frailty and poorer performance in TUG, 6MWT and leg strength measures, as well as a less fa-vourable body composition (higher ECM/BCM ratio, higher phase angle) and lower dis-ease-specific health-related quality of life (low CRQ). Several parameters (including TUG, 6MWT and CRQ) improved in a clinically relevant manner during PR. A correlation between cognitive performance and physical frailty appeared only to some extent for the ACE-R subcategory memory. A difference in training adherence could be seen among the groups classified by SPPB frailty state. Frail participants (SPPB≥3) fulfilled their planned training sessions most reliably (90%/target), while prefrail participants (SPPB=8-9) accomplished their schedules least (67%/target). Overall, our findings fit into previous data on frailty in severe chronic lung disease. They show a meaningful reduction of frailty through the multimodal concept of inpatient PR in LTx-candidates. Future studies should further address the topic to create a more reliable data base. They should additionally investigate to what extent the measured reduction of frailty after PR can be maintained in LTx-candidates and whether this success provides an actual advantage in quality of life and survival during and after transplantation.