Influence of metabolic syndrome on upper gastrointestinal disease.

A recent increase in the rate of obesity as a result of insufficient physical exercise and excess food consumption has been seen in both developed and developing countries throughout the world. Additionally, the recent increased number of obese individuals with lifestyle-related diseases associated with abnormalities in glucose metabolism, dyslipidemia, and hypertension, defined as metabolic syndrome (MS), has been problematic. Although MS has been highlighted as a risk factor for ischemic heart disease and arteriosclerotic diseases, it was also recently shown to be associated with digestive system disorders, including upper gastrointestinal diseases. Unlike high body weight and high body mass index, abdominal obesity with visceral fat accumulation is implicated in the onset of various digestive system diseases because excessive visceral fat accumulation may cause an increase in intra-abdominal pressure, inducing the release of various bioactive substances, known as adipocytokines, including tumor necrosis factor-α, interleukin-6, resistin, leptin, and adiponectin. This review article focuses on upper gastrointestinal disorders and their association with MS, including obesity, visceral fat accumulation, and the major upper gastrointestinal diseases.