Persistent infection of Helicobacter pylori affects weight loss in obese population compared with persistent negative: A case-control study based on healthy Chinese.

Background: The relationship between Helicobacter pylori (H pylori) and body mass index (BMI) is still inconclusive. Not only the high rate of H pylori infection but also the increasing higher BMI levels are endangering Chinese today.

Methods: The aim of this research was to evaluate the association between different situations of H pylori infection and BMI values or levels in Chinese healthy population. A total of 39 091 individuals aged from 18 years to 80 years, performed healthy examination including a C/ C urease breath test ( C/ C-UBT), were included. Among them, 30 224 individuals only had one time of health examination, and 8867 had two or more times. A case-cohort data of 8752 with an interval time more than 6 months, collected by the first and the last time, were established from the latter. BMI groups are classified according to the China recommendation: low weight (<18.5 kg/m ), normal weight (18.5 ~ 23.9 kg/m ), overweight (24.0 ~ 27.9 kg/m ), and obesity (≥28.0 kg/m ).

Results: The rate of H pylori infection among low weight, normal weight, overweight, and obesity was 43.2%, 44.7%, 46.4%, and 48.0%, respectively (P = .000). H pylori infection increased the risk of higher level of BMI (OR = 1.077, 95% confidence interval = 1.036-1.119, χ  = 14.048, P = .000) with adjustments for sex and age. In the case-control study, the rate of persistent negative, persistent infection, new infection, and eradicated infection was 39.5%, 25.8%, 15.8%, and 18.9%, respectively, with a median interval time of 13 months. The mean obesity BMI descend values in the persistent negative subgroup were lower than those in the persistent infection subgroup (-0.21 ± 1.19 kg/m vs -0.003 ± 1.01 kg/m , P = .021). But the change of BMI classifications had no difference between the subgroups of H pylori infection in different BMI levels.

Conclusions: H pylori infection was positively correlated with higher BMI levels. And H pylori persistent infection had a negative effect on the fall of BMI values in Chinese obese population.