Bariatric surgery: a promising solution for nonalcoholic steatohepatitis in the very obese

The management of nonalcoholic fatty liver has been limited by a paucity of well-conducted studies that are of sufficient duration and quality to determine the outcome, which is best defined by liver biopsy. The mainstays, diet and physical activity plus behavioral modifications, are not always successful, particularly in the very obese. Although it is intuitive to expect that weight loss should diminish steatosis, only limited evidence exists that liver enzymes improve with reduction in body weight. The available pharmacologic therapy has focused on the two limbs of the pathogenetic basis for nonalcoholic steatohepatitis (NASH), insulin resistance and oxidative stress, but with quite limited success. Neither behavioral, nor dietary, nor drug therapy has been particularly effective either in obesity or NASH. In the severely obese, the fatty liver and its stages often have progressed to NASH or cirrhosis even before contemplating therapy. In the severely obese, the best therapeutic modality is bariatric surgery, which is safe and has been successful in producing a 61% weight loss overall. The result is improvement in diabetes mellitus, the metabolic syndrome, and presumably its sequelae. Early reports (and procedures) were attended with dramatic weight loss but markedly aggravated the inflammatory liver disease. In recent trials with more modest weight loss and less malnutrition, bariatric surgery reduced the fat, inflammation, and even the fibrosis in well-documented NASH. These promising procedures will undoubtedly increase and constitute the major therapeutic modality for those who are severely obese.