Sarcopenic Obesity in Liver Transplanted Patients

Overview

The prevalence of obesity in cirrhotic patients who are candidates for liver transplantation (LT) is increasing, a phenomenon consistent with the increased prevalence of obesity in the general population. On the other hand, in liver patients on the waiting list for transplantation it is often observed sarcopenia. The combination of the two condition is defined sarcopenic obesity, which combines the negative synergy deriving from the two conditions. In this study the investigators will evaluate, for the first time, the prevalence of sarcopenic obesity in subjects undergone LT and determine the possible associated risk factors, particularly the role of immunosuppressive treatment with calcineurin inhibitors in addition to dietary habits and physical activity.

Obesity is a clinical condition characterized by excessive body weight due to the accumulation of adipose tissue, which represents a risk to health. In particular, obesity represents a risk factor for cardiovascular diseases, metabolic syndrome, NAFLD, and significantly increases the risk of mortality compared to normal weight subjects. It has been reported that the presence of obesity represents a risk factor for post-operative complications in patients undergone LT, increasing the mortality risk in those with the highest degree of obesity. At the same time, an evaluation obesity on the basis of body mass index (BMI) does not take in account the real body composition in terms of fat mass and muscle mass, which are more effective prognostic factors. Data of the literature report that patients undergoing liver transplantation (LT) have an average weight gain of 9 kg during the first year following the transplant, whereas in the second year, it would be observed about 24% incidence of obesity that would reach 30-38% in the third year. However, in all these studies the evaluation of de novo obesity is biased by the lack of data on the body weight of the patients prior their inclusion in the waiting list or to the use of dry body weight in patients mostly decompensated, or the loss of patients at the follow up. On the other hand, in liver patients on the waiting list for transplantation it is often observed sarcopenia, a syndrome characterized by progressive and generalized loss of skeletal muscle mass and strength associated with an increased risk of adverse events such as disability, poor quality of life and death. In this clinical setting, it has been reported in a percentage ranging from 41% to 68 %. The combination of the two condition defined sarcopenic obesity, which combines the negative synergy deriving from the two conditions, has been reported to be 20-40% in patients on the waiting list for liver transplantation. In addition, calcineurin inhibitors, which represent the backbone of anti-rejection therapy, have been investigated for their negative effect on muscle mass. In this study the investigators will evaluate, for the first time, the prevalence of sarcopenic obesity in subjects undergone LT and assess the possible associated risk factors, particularly the role of immunosuppressive treatment with calcineurin inhibitors (Ciclosporin and Tacrolimus), iin addition to dietary habits and physical activity. To achieve this goal the investigators will first screen all liver transplanted patients for muscle strenght and then all subjects with reduced muscle strenght will undergo bioelectrical impedance analysis (BIA). The presence of both conditions will allow us to identify subjects with sarcopenic obesity. Finally, the immunosuppressive therapy will be compared in liver transplanted patients with and without sarcopenic obesity. The evaluation of risk factors for obesity will be completing by the assessment of dietary habits and physical activity.