Impact of frailty and its inter-relationship with lean tissue wasting and malnutrition on kidney transplant waitlist candidacy and delisting

Summary Background & aims Frailty and body composition contribute to adverse pre-transplant outcomes including hospitalization and waitlist mortality, but the interaction between frailty and body composition remains uncertain. Methods Frailty was diagnosed by Clinical Frailty Score (CFS) and a standard Frailty Questionnaire (FQ). Nutrition was evaluated by serum albumin level, subjective global assessment (SGA) and comprehensive malnutrition-inflammation score (MIS). Body composition was assessed by bioimpedance spectroscopy. All patients were followed for three years. Primary outcome measure was a composite of death and permanent removal from waitlist. Secondary outcomes were emergency room attendance and hospitalization. Results 432 prevalent peritoneal dialysis (PD) patients were recruited. 148 (34.3%) were listed on transplant waitlist. Frailty, age and comorbidity load predicted waitlisting. With time, 47 patients were delisted. Frailty by FQ (p = 0.028), serum albumin level (p = 0.005) and waist circumference (p = 0.010) predicted delisting after adjustment for confounders. Frailty significantly interacted with lean tissue wasting (FQ: p = 0.002, CFS: p = 0.048), and MIS (FQ: p = 0.004; CFS: p = 0.014) on delisting. Lean tissue wasting caused 2.45 times risk of delisting among frail individuals identified by FQ (p = 0.020), while serum albumin and presence of diabetes mellitus predicted risk of delisting among non-frail individuals. Lean tissue wasted frail subjects had a higher all-cause and infection-related hospitalization. Conclusion Frailty predicted both kidney transplant waitlisting and subsequent delisting. Frailty interacted with body composition on transplant waitlist delisting. Lean tissue wasting and malnutrition independently predicted delisting in frail and non-frail listed subjects respectively.