omega-3 vs very low calorie diet for liver size reduction

Conditions: Obesity, Morbid; Obesity; NAFLD; NASH - Nonalcoholic Steatohepatitis

Summary: a recent review demonstrated that non-alcoholic fatty liver disease (nafld) affects 10-35% of the adult population worldwide, with the prevalence approaching 85-100% in obese populations. current standard treatment for liver reduction before surgery is the use of a very low calorie liquid diet (vlcld). multiple studies have shown that a 2-4 week diet with a vlcd will reduce liver volume, in preparation for surgery. omega-3 (ω-3) polyunsaturated fatty acids (pufas) have been suggested as a treatment for nafld. the primary aim of this study is to compare ω-3 pufas and a vlcld and their effect on left lobe live size before bariatric surgery.

non-alcoholic fatty liver disease (nafld) is defined by the pathological accumulation of fat in the liver when no other explanatory disease is present: it encompasses isolated hepatic steatosis, non-alcoholic steatohepatitis (nash) cirrhosis, and is a frequent accompaniment of obesity and insulin resistance. a recent review demonstrated that nafld affects 10-35% of the adult population worldwide, with the prevalence approaching 85-100% in obese populations. although frequently asymptomatic and relatively benign, nafld has the potential to progress to cirrhosis. cirrhosis, when decompensated, has a poor prognosis. also, nafdl will be accompanied invariably with increased liver volume, which will directly increase the level of difficulty of upper gastrointestinal surgery, such as bariatric surgery, specifically for the visualization of the gastro-esophageal junction. bleeding is also more frequent with larger fattier left liver lobes. the combination of these factors may lead to conversion to open surgery, thus: increasing postoperative pain due to larger incisions, prolonging postoperative recovery times and increasing the risks of infection and hernias. current standard treatment for liver reduction before surgery is the use of a very low calorie liquid diet (vlcld). multiple studies have shown that a 2-4 week diet with optifast® will reduce liver volume, in preparation for surgery. omega-3 (ω-3) polyunsaturated fatty acids (pufas) have been suggested as a treatment for nafld. they have several potential mechanisms of action, the most important being to alter hepatic gene expression, thereby switching intracellular metabolism from lipogenesis and storage to fatty acid oxidation and catabolism. there is also evidence that they improve insulin sensitivity, are anti-inflammatory and reduce tnf levels lipogenesis thus offering several potential therapeutic mechanisms.

Eligibility criteria:
inclusion criteria: participants must meet all of the following inclusion criteria: * fulfilled criteria for bariatric surgery as coined by national institutes of health conference (a body mass index (bmi) of 40 or more, or a bmi of 35 or more with a serious health problem linked to obesity, such as type 2 diabetes, heart disease, or sleep apnea) * their age is ≥18 years and ≤70 years * able and willing to give written consent * the patient is willing to perform the pre-operative tests required for this study. exclusion criteria: participants who meet any of the following criteria at the time of the baseline visit are not eligible to be enrolled in this study: * prior bariatric surgery * patient must not have any acute or chronic alteration of liver function (i.e. cirrhosis, active or chronic hepatitis, congenital hepatic disease, etc.) * prior hepatic surgery * contra-indication to general anesthesia * any medical condition, which in the judgement of the investigator and/or designee makes the subject a poor candidate for the investigational procedure * pregnant or lactating female (women of child bearing potential must take a pregnancy test prior to surgery) * patients receiving medication that would alter hepatic function significantly. * patients with ascites. * history of alcohol abuse: \>3 standard drinks/day in men or \>2 standard drinks/day in women (one standard drink being defined as 12 ounces of 5% beer, 5 ounces of 12% wine or 1.5 ounces of 40% liquor). * patients consuming ω-3 supplements on a regular basis.