Global Performance Status Score: A New Tool to Assess Physical Performance in Kidney Transplant Patients

Background. Information on physical performance in renal transplantation is limited because of the shortage of specifically designed evaluation instruments. Therefore, we elaborated and validated the Global Performance Status (GloPerSta) score to provide a new and comprehensive tool, exploring the different components of physical performance in kidney transplant patients.Methods. We elaborated the GloPerSta score on the basis of the data obtained from a cross-sectional study, in which we evaluated the physical performance of a cohort of kidney transplant patients. The results of these analyses were weighted to describe the different contribution of any single test, via the generation of a structural equation model, resulting in the definition of the GloPerSta. Then, to internally validate this score, we studied its correlation with clinical parameters and quality of life (evaluated as KDQOL-SF, Kidney Disease Quality of Life-Short Form) in the same patient population.Results. We enrolled 132 patients in whom the functional tests revealed a great heterogeneity. GloPerSta allowed the stratification of the patients in 3 different physical performance categories (low: score 0-11; medium: 12-22; high: 23-33). Internal validation showed that GloPerSta was directly and significantly correlated with the quality of life and allograft function, independent of the time from transplantation.Conclusions. The GloPerSta is a reliable tool to assess physical performance in a kidney transplant population. Its application might be of help in identifying patients needing intensive and personalized rehabilitation programs.