14 DAY TRIAL // A new study carried out by Seattle Children's Hospital and the University of Washington, based on data from the Organ Procurement and Transplantation Network (OPTN), concluded that children who are too thin or, on the contrary, obese, have higher mortality risks within the first year after liver transplantation or later on, respectively.
For this research, the scientists gathered data from the OPTN on 7,942 patients under 18 years of age, with full BMI data, who underwent primary liver transplantation between 1987 and 2007.
They divided the patients into five categories, according to their BMI: severely thin, thin, normal weight, overweight and obese; 61% of patients had a normal weight during the study period.
According to the results of the study, thin or severely thin children had a lower survival rate (84%) at one year after surgery than normal weight or overweight kids (89%).
During the first year after transplantation, obese pediatric patients had a normal survival rate, but by the 12th year after LT, they had a lower survival rate (72%) than those of normal weight or overweight (77%).
So, the authors concluded that obesity seriously affected survival rates of children, over five years after LT, and they hypothesized that it was the post metabolic syndrome (PTMS) that contributed to the late morbidity and mortality, because of the time it takes long-term obesity-related conditions like diabetes, hypertension, and hyperlipidemia, to develop.
Also, using immunosuppressive therapy for a long time improves patients' survival but it can also aggravate the effects of PTMS.
Lead study author, André Dick, MD, from Seattle Children's Hospital and the University of Washington, said that “further research is needed to determine the optimal immunosuppressive regimen that will lessen the effects of PTMS.
“Pre- and post-transplant identification of malnourished or obese pediatric patients, along with optimization of their modifiable risk factors will help to best use scarce donor organs and maximize patient survival.”
Obesity is a serious problem, and childhood obesity rates are increasing at an alarming rate, according to the World Health Organization (WHO) data, which asserts that 22 million children worldwide, under the age of five, are overweight.
Dr Dick added that “controversies exist regarding the mortality of patients undergoing liver transplantation at the extremes of body mass index (BMI), and in pediatric patients weight is typically the only factor considered in survival analysis.
“Our study is the largest thus far to report on the impact of pre-transplant BMI on post liver transplant survival in the pediatric population.”
The November issue of Liver Transplantation, a peer-reviewed journal of the American Association for the Study of Liver Diseases (AASLD), has published details of the ten-year survival analysis.