Inevitability of disease recurrence after liver transplantation for NAFLD cirrhosis

Background & Aims

Liver transplantation (LT) is the only available treatment for end-stage non-alcoholic fatty liver disease (NAFLD) (related decompensated cirrhosis and/or hepatocellular carcinoma). The aim of our study was to evaluate the risk of disease recurrence after LT and the factors influencing it.

Method

This retrospective multicenter study included adults transplanted for NAFLD cirrhosis between 2000 and 2019 in 20 participating French-speaking centers. Disease recurrence (steatosis, steatohepatitis and fibrosis) was diagnosed from liver graft biopsies.

Results

We analyzed 150 patients with at least one graft liver biopsy available ≥6 months after transplantation, among 361 patients transplanted for NAFLD. The median (IQR) age at LT was 61.3 (54.4-64.6) years. The median follow-up after LT was 4.7 (2.8-8.1) years. The cumulative recurrence rates of steatosis and steatohepatitis at 5 years were 80.0% and 60.3%, respectively. Significant risk factors for steatohepatitis recurrence in multivariate analysis were recipient age at LT <65 years (odds ratio [OR] 4.214; p = 0.044), high-density lipoprotein-cholesterol <1.15 mmol/L after LT (OR 3.463; p = 0.013) and grade ≥2 steatosis on the graft at 1 year after LT (OR 10.196; p = 0.001). The cumulative incidence of advanced fibrosis (F3-F4) was 20.0% at 5 years after LT and significant risk factors from multivariate analysis were metabolic syndrome before LT (OR 8.550; p = 0.038), long-term use of cyclosporine (OR 11.388; p = 0.031) and grade ≥2 steatosis at 1 year after LT (OR 10.720; p = 0.049). No re-LT was performed for NAFLD cirrhosis recurrence.

Conclusion

Our results strongly suggest that recurrence of initial disease after LT for NAFLD is inevitable and progressive in a large proportion of patients; the means to prevent it remain to be further evaluated.

Impact and implications

Non-alcoholic fatty liver disease (NAFLD) is a growing indication for liver transplantation, but the analysis of disease recurrence, based on graft liver biopsies, has been poorly studied. Cumulative incidences of steatosis, steatohepatitis and NAFLD-related significant fibrosis recurrence at 5 years were 85.0%, 60.3% and 48.0%, respectively. Grade ≥2 steatosis on graft biopsy at 1 year (present in 25% of patients) is highly predictive of recurrence of steatohepatitis and advanced fibrosis: bariatric surgery should be discussed in these patients specifically.

Efficacy of a liquid low-energy formula diet in achieving preoperative target weight loss before bariatric surgery

A preoperative weight loss of 8 % is a prerequisite to undergo bariatric surgery (BS) in Denmark. The aim of the present study was to evaluate the efficacy of a 7- or an 11-week low-energy diet (LCD) for achieving preoperative target weight before BS. A total of thirty obese patients (BMI 46·0 (sd 4·4) kg/m(2)) followed an LCD (Cambridge Weight Plan(®), 4184 kJ/d (1000 kcal/d)) for 7 or 11 weeks as preparation for BS. Anthropometric measurements including body composition (dual-energy X-ray absorptiometry), blood parameters and blood pressure were assessed at weeks 0, 7 and 11. At week 7, the majority of patients (77 %) had reached their target weight, and this was achieved after 5·4 (sem 0·3) weeks. Mean weight loss was 9·3 (sem 0·5) % (P < 0·01) and consisted of 41·6 % fat-free mass (FFM) and 58·4 % fat mass. The weight loss was accompanied by a decrease in systolic and diastolic blood pressure (7·1 (sem 2·3) and 7·3 (sem 1·8) mmHg, respectively, all P < 0·01) as well as an improved metabolic profile (8·2 (sem 1·8) % decrease in fasting glucose (P < 0·01), 28·6 (sem 6·4) % decrease in fasting insulin (P < 0·01), 23·1 (sem 2·2) % decrease in LDL (P < 0·01), and 9·7 (sem 4·7) % decrease in TAG (P < 0·05)). Weight, FFM and fat mass continued to decrease from week 7 to 11 (all P < 0·01), whereas no additional improvements was observed in the metabolic parameters. Severely obese patients can safely achieve preoperative target weight on an LCD within 7 weeks as part of preparation for BS. However, the considerable reduction in FFM in severely obese subjects needs further investigation.

Neuroimaging and neuromodulation approaches to study eating behavior and prevent and treat eating disorders and obesity

Functional, molecular and genetic neuroimaging has highlighted the existence of brain anomalies and neural vulnerability factors related to obesity and eating disorders such as binge eating or anorexia nervosa. In particular, decreased basal metabolism in the prefrontal cortex and striatum as well as dopaminergic alterations have been described in obese subjects, in parallel with increased activation of reward brain areas in response to palatable food cues. Elevated reward region responsivity may trigger food craving and predict future weight gain. This opens the way to prevention studies using functional and molecular neuroimaging to perform early diagnostics and to phenotype subjects at risk by exploring different neurobehavioral dimensions of the food choices and motivation processes. In the first part of this review, advantages and limitations of neuroimaging techniques, such as functional magnetic resonance imaging (fMRI), positron emission tomography (PET), single photon emission computed tomography (SPECT), pharmacogenetic fMRI and functional near-infrared spectroscopy (fNIRS) will be discussed in the context of recent work dealing with eating behavior, with a particular focus on obesity. In the second part of the review, non-invasive strategies to modulate food-related brain processes and functions will be presented. At the leading edge of non-invasive brain-based technologies is real-time fMRI (rtfMRI) neurofeedback, which is a powerful tool to better understand the complexity of human brain-behavior relationships. rtfMRI, alone or when combined with other techniques and tools such as EEG and cognitive therapy, could be used to alter neural plasticity and learned behavior to optimize and/or restore healthy cognition and eating behavior. Other promising non-invasive neuromodulation approaches being explored are repetitive transcranial magnetic stimulation (rTMS) and transcranial direct-current stimulation (tDCS). Converging evidence points at the value of these non-invasive neuromodulation strategies to study basic mechanisms underlying eating behavior and to treat its disorders. Both of these approaches will be compared in light of recent work in this field, while addressing technical and practical questions. The third part of this review will be dedicated to invasive neuromodulation strategies, such as vagus nerve stimulation (VNS) and deep brain stimulation (DBS). In combination with neuroimaging approaches, these techniques are promising experimental tools to unravel the intricate relationships between homeostatic and hedonic brain circuits. Their potential as additional therapeutic tools to combat pharmacorefractory morbid obesity or acute eating disorders will be discussed, in terms of technical challenges, applicability and ethics. In a general discussion, we will put the brain at the core of fundamental research, prevention and therapy in the context of obesity and eating disorders. First, we will discuss the possibility to identify new biological markers of brain functions. Second, we will highlight the potential of neuroimaging and neuromodulation in individualized medicine. Third, we will introduce the ethical questions that are concomitant to the emergence of new neuromodulation therapies.