International guidelines rate class III (morbid) obesity (body mass index [BMI]≥40 kg/m2) as a relative contraindication for liver transplantation requiring further research.
Moreover, data on the mortality risk in candidates with a BMI of 30-34.9 and 35-39.9 kg/m2 are weak.
Dr Barone and colleagues compared post-operative complications and mortality risks in all obese candidates vs candidates with a BMI of 18.5-29.9 assumed as controls.
The team searched the Cochrane library, PubMed, Scopus, Web-of-Science and article reference lists, restricted to the English language, and selected cohort studies.
The team analyzed all-causes mortality, post-operative and cardiopulmonary complications, hospital and intensive care unit (ICU) length of stay.
There were 2 reviewers that independently extracted the studies data and a third one resolved discrepancies.
The research team found that 24 studies comprizing 132,162 patients met the inclusion criteria.
As compared to controls, mortality risk was increased at all time-periods for a BMI of 40 or more, at 30 days for a BMI of 30-34.9 and in none of the considered time-periods for a BMI of 35-39.9.
The team noted that post-operative complications were significantly higher for a BMI more than 30 and 30-34.9.
Due to the shortage/absence of data, we evaluated cardiopulmonary complications, hospital and ICU length of stay only in the BMI 30 or more category.
The researchers observed that in these patients, only cardiopulmonary complications were increased as compared to controls.
Dr Barone's team concludes, "Morbid obesity has an impact on patients’ survival after liver transplantation."
"However, since even a BMI more than 30 increases post-transplant complications, new strategies should be included in the liver transplantation program to favor weight loss in all obese candidates."