The Effects of Bariatric Surgeries on Non-Alcoholic Fatty Liver Disease
Non-alcoholic fatty liver disease (NAFLD) is the most common form of chronic liver disease. In the absence of chronic alcohol abuse or other liver diseases, NAFLD incorporates a wide spectrum of liver pathologies and is defined by fatty infiltration of the liver (simple hepatosteatosis). It can progress to non-alcoholic steatohepatitis (NASH) and later fibrosis, cirrhosis, and eventually some patients may develop hepatocellular carcinoma with or without cirrhosis. The exact cause of NAFLD is yet to be cleared and it is, therefore, an active area for research. The diagnosis of NAFLD is achieved through histological examination of liver biopsies (invasive), non-invasive markers using serum biomarkers and imaging techniques are still under development. Pathological diagnosis can be then subcategorized based on several scoring systems. More widely used are the Brunt Score or NAS (NAFLD activity score) and the Kleiner's modified NAS.
Obesity is highly associated with NAFLD, as the epidemic of obesity has made NAFLD more prevalent. In addition insulin resistance has been linked to NAFLD and this is explained by the increased influx of free fatty acids (FFAs) into the liver. FFA undergoes either β-oxidation or esterification with glycerol to form triglycerides (TGs), resulting in an additional source of fat in the liver. Due to the strong association of NAFLD with obesity, weight reduction procedures are used for the management of NAFLD. In fact, this has been shown to be effective by several studies. However, other studies have reported liver deterioration after bariatric intervention. This conflict is what makes the effects of bariatric procedures a challenging field for further studies. Consequently in this study we are aimed to examine histologic, metabolic and liver function changes induced by the different therapeutic bariatric procedures.
Non-Alcoholic Fatty Liver Disease.
|Study Design:||Observational Model: Cohort
Time Perspective: Prospective
|Official Title:||The Effects of Bariatric Surgeries on Non-Alcoholic Fatty Liver Disease|
- Assessment of NAFLD histological changes after bariatric surgery (adjustable gastric banding, sleeve gastrectomy, gastric bypass, and duodenal switch). [ Time Frame: Intra-operatively, 3 months and 1 year postoperatively. ] [ Designated as safety issue: Yes ]Histological evaluation is done by applying the NAFLD activity score (NAS). The stage of fibrosis will be determined by the five-point (stage 0 to 4) scale.
- Assessment of liver function after bariatric surgery. [ Time Frame: Preoperatively, 3 months, 6 months, 1 year and annually for 5 year postoperatively. ] [ Designated as safety issue: Yes ]
- Measure serum albumin, bilirubin, INR, anti-thrombin-III, ALT, GGT, AST, protein C and S levels.
- Measure albumin synthesis using radiolabeled amino acids.
- Assessment of NAFLD associated morbidities by detecting the systemic inflammatory changes after bariatric surgery. [ Time Frame: preoperatively, 3 months, 6 months, 1 year and annually for 5 year postoperatively. ] [ Designated as safety issue: Yes ]- Study systemic inflammatory changes by measuring the serum levels of several inflammatory mediators: ESR, C-reactive protein, interleukins (IL-1, IL-4, IL-6, IL-8, IL-10, IL-16), adipokines (adiponectin, leptin, adipsin and Chemerin), MCP1, osteopontin, and growth factors (TNF-α, and VEGF).
- Assessment of NAFLD associated morbidities by detecting the local inflammatory changes after bariatric surgery. [ Time Frame: Baseline (tissues obtained intraoperatively). ] [ Designated as safety issue: Yes ]
- Hepatic expression of α-SMA, collagen α1, TGF-β1, MCP-1, IL-6, IL-8, leptin and adiponectin receptors. PAI1, ACRP30, ADIPOQ.
- Visceral adipose tissue to assess the expression of NOD-like receptor pyrin domain-containing-3 inflammasome (Nlrp3); are inflammatory markers that recognize certain signals that leads to caspase-1 activation and subsequent IL-1 and IL-18.
- Subcutaneous adipose tissue to assess the expression of adiponectin, IL-6 and TNF-α.
- Assessment of NAFLD associated morbidities by detecting the metabolic changes after bariatric surgery. [ Time Frame: Preoperative, 3 months, 6 months, 1 year and annually for 5 years postoperatively. ] [ Designated as safety issue: Yes ]
- Hormonal changes: serum levels of ghrelin, peptide YY, amylin, cholecystokinin, insulin, glucagon, epinephrine, and cortisol.
- Non-hormonal changes: HbA1c, FFA, HDL, cholesterol, triglycerides, fasting glucose.
- Assessment of NAFLD associated morbidities by detecting the endothelial changes after bariatric surgery. [ Time Frame: Preoperative, 6 months, 1, 2 and 5 years postoperatively. ] [ Designated as safety issue: Yes ]
- Doppler Ultrasound (Duplex) for the carotid arteries.
- Measuring the levels of progenitor cells.
- Studying the genetic factors expressing for the inflammatory changes differences in responders. [ Time Frame: Baseline (for liver, visceral and subcutaneous fat). Postoperatively (for liver only): 3 months, 1 year and 5 years after the surgery. ] [ Designated as safety issue: Yes ]
- TMA construction using the formalin stored liver, visceral fat and abdominal wall muscle.
- Detecting mRNA expression from frozen tissue (liver, visceral fat and abdominal wall muscle) with respect of inflammation, insulin action, lipid metabolism, liver regression and apoptosis.
- Deep gene sequencing for subgroup of patients with variables clinical responses or with genetic differences determined form the above testing.
- Long-term follow-up to examine the correlation between the type of surgery and clinical outcomes associated with NAFLD (liver cirrhosis, incidence of cancer, and mortality). [ Time Frame: 5 years ] [ Designated as safety issue: Yes ]Histological evaluation is done by applying the NAFLD activity score (NAS). The stage of fibrosis will be determined by the five-point (stage 0 to 4) scale.
- Testing the efficacy of the non-invasive images in the diagnosis of NAFLD. [ Time Frame: Baseline (preoperatively), 1 year and 5 years postoperatively. ] [ Designated as safety issue: Yes ]
- Magnetic Resonance Studies.
Biospecimen Retention: Samples With DNA
Blood (serum, plasma, and RNA isolate) Liver core biopsy Subcutaneous fat Visceral fat Abdominal wall muscle
|Study Start Date:||June 2012|
35 consecutive patients referred for bariatric surgery will be recruited either at the obesity clinic, or from inpatient (scheduled for bariatric surgery). A detailed history and a complete physical examination will be done at the first visit along with anthropometric measures; routine blood tests, liver function, hormonal assessment, and certain metabolic and inflammatory markers will be evaluated. They will also have an abdominal ultrasound for initial NAFLD assessment, fibroscan to detect liver fibrosis, and an MRI to measure hepatic fat content and body fat composition including intra-abdominal and extra-abdominal fat. These patients will be asked to lose a certain amount of kilos (depending on their BMI and the surgeon preference) out of their original weight, in order to become candidates for bariatric surgery at King Saud University Hospital (KKUH).
At the second visit, (if they lose the recommended amount weight) we will assess their weight loss; obtain blood for the same hormonal and inflammatory markers assessment. Nonetheless, if they did not lose weight and the treating surgeon gave them a third appointment, we will consider their third visit as a second visit; preforming all the investigations mentioned above. In this case we will interpret their results with respect to the total duration of "before surgery" weight loss.
During the operation, tissue biopsy will be taken with a core needle biopsy for the liver and a sharp non-thermal instrument for subcutaneous fat, visceral fat, and abdominal muscle immediately after skin incision. A CAP certified tissue manager would process all tissues. Liver biopsy will be sliced it to two parts; the first half is for histological evaluation, but the other half will be stored for tissue studies. The histologic slides will be stained with hematoxylin and eosin (H&E), and Masson Trichrome stains for microscopic evaluation. This evaluation will be provided by a single histopathologist who will be blinded to the patients' clinical condition, and the order of the biopsy.
After the surgery follow up appointments will be scheduled 3 months, 6 months, 1 year, and annually till 5 years. The followings will be done in each visit:
- Thorough physical exam as per the CRF.
- Take a blood sample to evaluate liver function, metabolic, and inflammatory changes using the same parameters as those in the baseline.
- Request for: fibroscan and abdominal ultrasound. Second, third and fourth liver biopsies will be taken percutaneously 3 months, 1 year, and 5 years following the initial biopsy respectively. These biopsies will be obtained using core tissue biopsy with ultrasound guidance for the same histological assessment and tissue studies. Another MRI will be schedule 1 year after the surgery.
Specimens collected under this trial will be part of the King Saud University Liver Disease Research Centre Biobanking and will follow all policy and procedures within the biobanking protocol as approved by the IRB committee.
|Contact: Maya Wardeh, MBA||+966538966583||Mwardeh.email@example.com|
|Contact: Atheer Al-Sabhan, (MBBSc)||+96650599995||Atheer.Sabhan@gmail.com|
|King Khalid University Hospital||Recruiting|
|Riyadh, Saudi Arabia, 7805|
|Sub-Investigator: Fahad Bamehriz, MBBS|
|Sub-Investigator: Hisham Al-Khalidi, MBBS|
|Sub-Investigator: Talal Al-Tuwaijri, MBBS|
|Sub-Investigator: Amna Al-Mulhim, (MBBSc)|
|Sub-Investigator: Atheer Al-Sabhan, (MBBSc)|
|Sub-Investigator: Shaden Al-Amro, (MBBSc)|
|Principal Investigator:||Dr.Mazen Hassanain, MBBS FRCSC PhD||King Khalid University Hospital,King Saud University,Riyadh,KSA.|