People who have the Helicobacter pylori (H. pylori) bacteria in their stomach may be more likely to have higher blood sugar levels, a sign of diabetes and prediabetes. This risk may be even greater in people who are obese.
"Lose weight to prevent diabetes."
Previous studies have looked at the relationship between H. pylori and diabetes risk. But the results of these studies have conflicted.
In order to better understand how H. pylori plays a role in diabetes, Yu Chen, Ph.D., M.P.H., of New York University School of Medicine, and Martin J. Blaser, M.D., also of New York University, looked at how H. pylori affected levels of HbA1c - a measure of blood sugar over three months and tool for diagnosing diabetes.
Their study is the first to look at the effects of H. pylori on HbA1c. More specifically, they studied how H. pylori affects HbA1c levels for people of different Body Mass Index (BMI) - a measure of body fat using height and weight.
"The prevalence of obesity and diabetes is growing at a rapid rate, so the more we know about what factors impact these conditions, the better chance we have for doing something about it," says Dr. Chen.
"Obesity is an established risk factor for diabetes and it is known that high BMI is associated with elevated HbA1c. Separately, the presence of H. pylori is also associated with elevated HbA1c," explains Dr. Blaser.
"We hypothesized that having both high BMI and the presence of H. pylori would have a synergistic effect, increasing HbA1c even more than the sum of the individual effect of either risk factor alone."
For their study, Dr. Chen and Dr. Blaser looked at data from 13,489 people who took part in two National Health and Nutrition Surveys.
They found exactly what they hypothesized. That is, having H. pylori in the stomach and a high BMI led to a greater increase in HbA1c than combining the individual effects of having either risk factor on its own.
While this study shows a link between H. pylori and HbA1c, it does not explain how the bacteria increases HbA1c levels.
Dr. Chen and Dr. Blaser think that H. pylori may have an impact on two different stomach hormones that help manage blood sugar levels.
According to the authors, more research is needed to understand how H. pylori effects a person's health, and how to rid the bacteria from people in different age groups and of different weights.
"If future studies confirm our finding, it may be beneficial for individuals at risk for diabetes to be tested for the presence of H. pylori and, depending on the individual's risk factor profile," says Dr. Chen.
The results of the current study are published in The Journal of Infectious Diseases.