MedWire News: People infected with a common bacterium called Helicobacter pylori have a reduced risk of reflux oesophagitis, Barrett's oesophagus and oesophageal cancer, researchers have found.

Previous studies have shown a link between infection with Helicobacter pylori, which can cause stomach ulcers, and a reduced risk of oesophageal cancer, explain Dr L Anderson, from Queen's University Belfast in the UK, and colleagues.

But they add that it is not known whether infection with the bacterium also reduces the acid reflux-related diseases of the foodpipe, such as reflux oesophagitis and Barrett's oesophagus, which can lead to oesophageal cancer.

To investigate, the team studied 230 patients with reflux oesophagitis, 224 with Barrett's oesophagus, 227 with oesophageal cancer and 260 members of the general public without such disorders.

Blood samples collected from all the participants were tested for Helicobacter pylori infection.

Analysis revealed that infection with Helicobacter pylori was associated with a 58% reduced risk of reflux oesophagitis, a 65% reduced risk of Barrett's oesophagus and more than a 50% reduced risk of oesophageal cancer.

The team also found that participants with a condition called gastric atrophy, in which the stomach muscles become weak and shrink, resulting in a lack of stomach acid, were less likely to develop these diseases than other people.

However, even after accounting for the presence of gastric atrophy, the association between infection with Helicobacter pylori and a reduced risk of reflux oesophagitis, Barrett's oesophagus and oesophageal cancer remained, says the team.

Writing in the journal Gut, Dr Anderson and team conclude: "Helicobacter pylori infection and gastric atrophy are associated with a reduced risk of oesophageal cancer, Barrett's oesophagus and reflux oesophagitis."

They add: "These data suggest that although gastric atrophy is involved, it may not fully explain the inverse associations observed with Helicobacter pylori infection."