It's a gram negative spiral shaped pathogenic bacterium which inhabits the human gastric mucosa. The bacterium is present in approximately half of the worlds population, but it causes symptomatic disease in only 10-15% of those infected where it invades the gastric epithelial lining [1].

India is a typical example of a developing country as far as Helicobacter pylori is concerned and more than 20 million Indians are estimated to suffer from peptic ulcer disease.

The prevalence of h pylori in the Indian subcontinent can be as high as 80% or more in rural areas. The most commonly recognised manifestation of H.pylori infection in India is peptic ulcer disease, particularly duodenal ulcer disease, which outnumbers gastric ulcers between 8:1 and 30:1. The population of Indians are approximately 1.2 billion. If the H. Pylori prevalence was 60%, more than 726 million individuals would be infected with h pylori. The estimated prevalence of duodenal ulcers is 3% and means that atleast 18 million people could need h pylori therapy [4-9].  

pylori infection most often presents as a predominantly antral gastritis with normal or increased acid production. Local gastrin production may be increased, but hypergastrinemia (increased serum gastrin) is uncommon. When inflammation remains limited to the antrum, increased acid production results in greater risk of duodenal peptic ulcer. In other patients gastritis may progress to involve the gastric body and fundus. This multifocal atrophic gastritis is associated with patchy mucosal atrophy, reduced parietal cell mass and acid secretion, intestinal metaplasia, and increased risk of gastric adenocarcinoma. Thus, there is an inverse relationship between duodenal ulcer and gastric adenocarcinoma that correlates with the pattern of gastritis.H. pylori organisms have adapted to the ecologic niche provided by gastric mucus. Its virulence is linked to certain factors like flagella, urease, adhesins, toxins. 4

The current gold standard to diagnose h.pylori infection invasively is two positive tests, which in India could be a combination of rapid urease test and examination of endoscopic biopsies by histology. The urea breath test is based on the generation of ammonia by the bacterial urease. The advantage of endoscopy is that symptomatic patients can be evaluated for mucosal disease. Endoscopy also allows one to take biopsy specimens that can be examined by histology, rapid urease tearing, brush cytology, or even culture. The other non invasive tests for active infection are urea breath test, stool antigen tests, and serology [2-3].

Prevalence of obesity in India is varying from rural to urban and state wise. An urban population and states with high socio economic status were found to be having high obesity prevalence. Recent studies have reported that India is a developing country which is in a transitional state of under nutrition due to poverty and obesity due to industrialisation and rapid urbanisation. In India, more than 135 million individuals are affected by obesity [10-1].

A study published in the noted medical journal Lancet says India is just behind US and china in this global hazard list of top ten countries with highest no. of obese people.

Body mass index, or BMI, is a persons weight in kilograms divided by the square of his/her height in metres. The national institute of health (NIH) has now defined BMI to be the deciding parameter to know if you are underweight, normal weight, overweight, or obese.

Several studies have been conducted over the past few decades regarding the relationship between Helicobacter pylori and BMI but the results have been contradictory.

There is an ongoing debate over the association between obesity and Helicobacter pylori. A recent ecological review of several cross sectional studies found an increase in Helicobacter pylori was associated with a decrease in obesity in the developed countries. This theory was further strengthened by the corroboration with several interventional studies stating that Helicobacter pylori eradication was associated with weight gain and an increase in BMI.

There are also a few neutral studies which state that Helicobacter pylori has no association with change in BMI nor does it cause obesity.

In Contrast to these studies, there has been a rise of several observational or clinical studies from developing countries reported a linear relationship between H. pylori positive infection and obesity.

However obesity can alter innate and adaptive immunity, with immunological impairment related to the grade of obesity, resulting in less maturation of monocytes into macrophages, reduced polymorphonuclear bactericidal capacity and a significant decrease in NK cell activity. This contributes to reduced defence of the body against Helicobacter pylori invasion. In light of the limited literature to assess the prevalence of Helicobacter pylori in patients reporting to hospitals from India and specifically South India, we aimed in this hospital based study to determine the estimate of Helicobacter pylori positive infections in a group of obese subjects reporting for upper GI endoscopy and compare it to a match control group (age and gender ) who had an upper GI endoscopy in the same period in the same setting, but had normal BMI. Based on the conflicting results of the current studies and available literature, we hypothesized, after controlling for age and gender,that we will be able to find out whether there is any correlation between Helicobacter pylori positive infections and obesity.

A case control study design was adopted in the department of endoscopy at a central hospital (Saveetha Medical College and Hospital).

A total of 120 patients who reported to the endoscopic division of Gastroenterology department of Saveetha Medical College and Hospital between January, 2019 – March 2019 were selected for the study. A consecutive test group consisting of 37 individuals defined with a BMI of more than or equal to 30kg/m^2 reporting to the gastroenterology department for upper GI endoscopy between the months January, 2019 – March, 2019 was formed. A group containing 83 patients with BMI < or equal to 30kg/m^2 who underwent upper GI endoscopy in the same Hospital and Gastroenterology Department, in the same duration were selected as controls. The control to test ratio was approximately 2.24.

We excluded patients with history of taking eradication therapy of Helicobacter pylori positive infections within 6 months, patients with acute infection and gastro intestinal bleeding or patients with history of proton pump inhibitor (PPI) or antibiotics intake 2 weeks before the endoscopic procedure as these factors may result in false negative results for Helicobacter pylori testing.

The data for both groups included the demographics ( age, gender ),IP number, Height, Weight, Blood group, symptoms on admission,provisional diagnosis, endoscopic and histological finding.

Standard technique was used to perform endoscopy on all patients to assess for Helicobacter pylori positive infection test. Patients were made to lie in the left lateral position with a mouth piece placed and adequate xylocaine was sprayed on their throats. Two antral biopsies were taken from antrum for each patient, as per the routine practice of the endoscopy unit, and submitted for histologic evaluation. No complication related to endoscopy was reported in any patient. The specimens were stained by hematoxylin and eosin stain or methylene blue. The laboratory investigator was not informed of the sample status to avoid investigator bias.

Body mass index (BMI) is a weight for height index used to classify individuals into categories such as underweight, normal, overweight, obese,etc.

A weighing scale was used to measure the weight of the patients. Height was taken in a standing position without shoes and light clothing.

Conflicts of interest: The author declares no conflict of interest.

Statistical Analysis was conducted using SPSS software. Descriptive analysis was conducted for the continuous and categorical variables. The different variables such as age, sex, height, weight, BMI, Helicobacter pylori positivity and negativity were first independently calculated and represented in the form of frequencies and percentages. Chi square tests were conducted to explore the relationship of continuous and categorical variables with the dependent variable. A p value of <0.05 was considered significant.