Development of a multivariable prediction model of functional exercise capacity in liver transplant recipients

Abstract

BackgroundThe assessment of the functional exercise capacity in liver transplant recipients might allow identifying functional disabilities and proposing a personalized exercise model for this population. AimTo develop a population-specific, multivariable prediction model of the six-minute walk distance (6MWD) in liver transplant recipients. MethodsThis cross-sectional study enrolled 70 participants (men/women: 47/23; age 53 ± 12 years; 32 ± 32 months after liver transplantation). Functional exercise capacity was assessed using the six-minute walk test, considering the 6MWD as the dependent variable. Demographic, anthropometric and current physical activity level (International Physical Activity Questionnaire [IPAQ]) entered the model as independent variables. Disease-specific markers—pre-transplant model end-stage liver disease (MELD) and fatigue (Fatigue Severity Scale [FSS])—also entered the full model as independent variables. ResultsPatients walked 421 ± 102 m and predicted values of six-minute walk distance (6MWDP) yielded a group average of 421 ± 64 m. The full multivariable model was 6MWDp=514.998−2.319×Ageyears+48.151×Sexmen=1,women=0−0.751×BMIkg/m2+28.396×IPAQcode−2.443×FSS+0.406×Timemonths−0.785×MELD (adjusted R2 = 0.329, SE of bias = 79 m), suggesting that both demographic and disease-specific information partially determines the functional exercise capacity. ConclusionsBetter functional capacity, i.e. higher 6MWD, is associated with sex (men), lower age, BMI, fatigue or pre-transplant MELD, and higher physical activity in liver transplant recipients.