A Case-Control Study of Association of Helicobacter Pylori Infection with Morbid Obesity in Taiwan

Abstract

Background Obesity is an increasing health problem in developed countries, where the prevalence of Helicobacter pylori infection is decreasing. Recent studies suggested colonization of the stomach by H pylori might affect gastric expression of appetite- and satiety-related hormone and patients cured of H pylori infection gained weight. It was hypothesized that H pylori could be a contributing pathogenic factor in childhood and adult obesity. Methods To determine whether H pylori infection is linked to obesity , a case-control study composed of 414 patients with morbid obesity (a body mass index [calculated as weight in kilograms divided by the square of height in meters] of 35 with serious comorbidity or a body mass index of 40) and 683 control subjects (a body mass index of <25) with a comparable socioeconomic status was conducted. Immunoglobulin G antibodies against H pylori were measured from frozen serum samples by an enzyme-linked immunosorbent assay. Logistic regression was used to calculate the odds ratio (OR) and 95% confidence interval (CI ). Results The overall seropositivity was significantly lower in obese patients (181 [43.7%] of 414) than controls (410 [60.0%] of 683) (OR, 0.50 ; 95% CI, 0.39-0.65; P<.001). Differences in the estimated risk of the presence of H pylori were more pronounced in younger age groups, with ORs of 0.32 (95% CI, 0.10-1.00; P = .05) in those aged 10 to 19 years, 0.55 ( 95% CI, 0.34-0.89; P = .01) in those aged 20 to 29 years, 0.49 ( 95% CI, 0 .30-0.80; P = .007) in those aged 30 to 39 years, and 0.58 (95% CI, 0.33-1 .00; P = .05) in those aged 40 years or older. Conclusions Our data indicated an inverse relationship between morbid obesity and H pylori seropositivity. These findings raise the hypothesis that a lack of H pylori infection, especially during childhood, might enhance the risk of the development of morbid obesity.