Relationship between metabolic syndrome-related parameters and endoscopic classification of gastroesophageal reflux disease: a Japanese health checkup cohort study.

BACKGROUND: The prevalence of gastroesophageal reflux disease (GERD) has increased worldwide, and metabolic syndrome (MS) was reported as a risk factor for its incidence. This study retrospectively evaluated the relationship between endoscopic GERD classification and MS-related parameters in a Japanese cohort. METHODS: We reviewed the medical records of 3,635 adults who underwent upper gastrointestinal endoscopy as part of health checkups. Based on endoscopic findings, GERD was classified according to the Los Angeles (LA) system. Body mass index (BMI), waist circumference, blood pressure (BP), and laboratory parameters-including glucose, low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), and triglycerides-were compared across the LA grade groups. RESULTS: The numbers of patients classified as LA grade N, M, A, B, C, and D were 2,557 (70.3%), 404 (11.1%), 566 (15.6%), 88 (2.4%), 19 (0.5%), and 1 (0.0%), respectively. BMI, waist circumference, and BP increased progressively from grade N to grade C. Patients with grades A or B exhibited significantly higher glucose, LDL-C, and triglyceride levels and lower HDL-C levels than grade N patients. A similar trend was observed in subgroup analyses of non-obese individuals (BMI < 25). Multivariate analyses identified increased BMI, triglyceride, and LDL-C levels as significant independent factors associated with erosive esophagitis of grade A or higher in both the overall and non-obese groups. CONCLUSIONS: Patients with more severe GERD grades demonstrated worsening of MS-related parameters, even in the absence of obesity. These parameters may be useful for predicting the endoscopic severity of GERD.