title: Modeling the effects of functional performance and post-transplant comorbidities on health-related quality of life after heart transplantation.
abstract: BACKGROUND
  Health-related quality of life and functional performance are important outcome measures following heart transplantation. This study investigates the impact of pre-transplant functional performance and post-transplant rejection episodes, obesity and osteopenia on post-transplant health-related quality of life and functional performance.
  
  
  METHODS
  Functional performance and health-related quality of life were measured in 70 adult heart transplant recipients. A composite health-related quality of life outcome measure was computed via principal component analysis. Iterative, multiple regression-based path analysis was used to develop an integrated model of variables that affect post-transplant functional performance and health-related quality of life.
  
  
  RESULTS
  Functional performance, as measured by the Karnofsky scale, improved markedly during the first 6 months post-transplant and was then sustained for up to 3 years. Rejection Grade > or =2 was negatively associated with health-related quality of life, measured by Short Form-36 and reversed Psychosocial Adjustment to Illness Scale scores. Patients with osteopenia had lower Short Form-36 physical scores and obese patients had lower functional performance. Path analysis demonstrated a negative direct effect of obesity (beta = - 0.28, p < 0.05) on post-transplant functional performance. Post-transplant functional performance had a positive direct effect on the health-related quality of life composite score (beta = 0.48, p < 0.001), and prior rejection episodes grade > or =2 had a negative direct effect on this measure (beta = -0.29, p < 0.05). Either directly or through effects mediated by functional performance, moderate-to-severe rejection, obesity and osteopenia negatively impact health-related quality of life. These findings indicate that efforts should be made to devise immunosuppressive regimens that reduce the incidence of acute rejection, weight gain and osteopenia after heart transplantation.
authors.affiliation: Transplant Center, Division of Cardiovascular Diseases, 383 PRB, Vanderbilt University Medical Center, Nashville, Tennessee 37232, USA. javed.butler@vanderbilt.edu
authors.forename: Javed
authors.initials: J
authors.lastname: Butler
authors.forename: Nicole S
authors.initials: NS
authors.lastname: McCoin
authors.forename: Irene D
authors.initials: ID
authors.lastname: Feurer
authors.forename: Theodore
authors.initials: T
authors.lastname: Speroff
authors.forename: Stacy F
authors.initials: SF
authors.lastname: Davis
authors.forename: Don B
authors.initials: DB
authors.lastname: Chomsky
authors.forename: John R
authors.initials: JR
authors.lastname: Wilson
authors.forename: Walter H
authors.initials: WH
authors.lastname: Merrill
authors.forename: Davis C
authors.initials: DC
authors.lastname: Drinkwater
authors.forename: Richard N
authors.initials: RN
authors.lastname: Pierson
authors.forename: C Wright
authors.initials: CW
authors.lastname: Pinson
mesh_terms: D001851:Bone Diseases, Metabolic / Q000453:epidemiology; D015897:Comorbidity; D005260:Female; D005500:Follow-Up Studies; D006084:Graft Rejection / Q000453:epidemiology; D016027:Heart Transplantation / Q000401:mortality / Q000523:psychology; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use; D017567:Karnofsky Performance Status; D008297:Male; D008875:Middle Aged; D015233:Models, Statistical; D009765:Obesity / Q000453:epidemiology; D017063:Outcome Assessment, Health Care; D011183:Postoperative Complications / Q000453:epidemiology*; D011788:Quality of Life; D012044:Regression Analysis; D012189:Retrospective Studies; D013997:Time Factors
chemical_list: D007166:Immunosuppressive Agents