Over the past decades, there has been a dramatic increase in obesity in the United States. Several studies have reported conflicting results for the impact of obesity on outcomes of liver transplantation (LT). This study aims to assess severe obesity's impact on LT outcomes and changes in body mass index (BMI) after transplantation.
All adult LT performed at Indiana University Health University Hospital between July 2001 and December 2018 were reviewed. A retrospective analysis for identified 2024 patients was conducted. BMI of recipients is subdivided into underweight, normal, overweight, class Ⅰ obesity, class Ⅱ obesity, and class Ⅲ obesity (<18.5; 18.5-24.9; 25‐29.9; 30‐34.9; 35‐39.9; ≥40 kg/m2, respectively). Survival outcomes were compared between each group. Post-transplant BMI was followed up in a sub-group of patients receiving LT from January 2008 to December 2018. A retrospective analysis for identified 1004 patients was conducted.
Among 2024 patients in the analytic cohort, 1.9% were underweight, 24.5% were normal, 32.6% were overweight, 25% were in class Ⅰ obesity, 9.3% were in class Ⅱ obesity, and 1.1% were in class Ⅲ obesity. There was no significant difference in patient and graft survival at 10-year follow-up with respect to recipient obesity. The 1, 3, 5, and 10-year graft and patient survivals in class Ⅲ obesity group were 97.0%, 92.1%, 87.0%, and 79.8% for patient survival and 94.4%, 85.1%, 79.8%, and 72.5% for graft survival.
Among 1004 patients identified in the sub-group, BMI of all groups except the underweight group declined in the first three months postoperatively. After the three months, the BMI of all groups except the class Ⅲ obesity group returned to the pre LT level by two years and reached a plateau by five years. In patients with class Ⅲ obesity, there was a significant increase in body weight after long-term follow-up.
In this study, class Ⅲ obesity is not associated with higher mortality. Obesity, including class Ⅲ obesity, should not be considered a contraindication to LT in the absence of other contraindications. Post-LT interventions are required to prevent significant weight gain in recipients with class Ⅲ obesity after transplantation.