Relationship of different metabolic obesity phenotypes with reflux esophagitis: a propensity score matching analysis

Obesity is associated with an increased risk of reflux esophagitis (RE). Metabolic abnormalities have been implicated in the pathogenesis of RE. However, the role of metabolic status in the risk of RE among individuals with varying degrees of obesity remains unclear. Therefore, our study aimed to assess the association between metabolic obesity phenotypes and the risk of RE.

This study included a cohort of 24,368 participants aged 18 years and older who underwent upper gastrointestinal endoscopy at the First Affiliated Hospital of Dalian Medical University during health checkups between January 1, 2008, and December 31, 2021. Among these participants, a total of 9,947 individuals were classified into four groups based on their obesity phenotype: metabolically healthy normal weight (MHNW), metabolically healthy obesity (MHO), metabolically unhealthy normal weight (MUNW), and metabolically unhealthy obesity (MUO). To account for potential confounding factors, multivariate logistic regression analysis was applied to examine the association between metabolic obesity phenotypes and the risk of RE, with stratification by sex and age.

Among all participants, the MUNW, MHO, and MUO groups demonstrated a higher risk of RE when compared to the MHNW group. After controlling for all confounding factors, the MUO group exhibited the highest risk, with an odds ratio (OR) of 3.723 (95% CI: 2.751-5.040) in males and 5.482 (95% CI: 4.080-7.367) in females. The prevalence of RE increased in proportion to the number of metabolic risk factors. Subgroup analyses, which accounted for all confounders, revealed that the MHO, MUNW, and MUO phenotypes were associated with an elevated risk of RE in individuals under 60 years old as well as those over 60 years old. Interestingly, a more comprehensive analysis indicated that obesity may have a greater effect on the risk of RE than metabolic disorders.

Both metabolic disorders and obesity were associated with an increased risk of RE. The effect of obesity on RE prevalence may be stronger than that of metabolic disorders, emphasizing the significance of obesity regardless of metabolic health status. Clinical interventions should address not only obesity but also metabolic disorders in order to reduce the risk of RE.