But they warned that treating non-symptomatic patients for the infection could be counterproductive, since there was also a trend for mortality to increase in those given eradication therapy.
The findings were based on 10-year follow-up data from a study looking at the effectiveness of a treatment programme for H pylori.
The original study included 8,407 UK patients aged between 40 and 49 without symptoms of dyspepsia who were screened for H pylori. Those testing positive were randomised for eradication therapy or placebo.
After 10 years, 140 of the participants had died. Of these; 46 per cent had died of cancer and 22 per cent of ischaemic heart disease (IHD).
The researchers reported that all-cause mortality rates over 10 years were 65 per cent higher in those who had tested positive for H pylori than in those who had tested negative. Those who tested positive were more than 2.4 times as likely as those who tested negative to have died of IHD in the following 10 years.
However, they found no increase in cancer mortality in those positive for H pylori infection.
After controlling for smoking, age, gender, alcohol consumption and social class, all-cause mortality remained 46 per cent higher in those positive for H pylori than in those who had tested negative.
When the researchers looked at the effect of eradication therapy on mortality rate, they found there was a trend towards higher mortality in those treated for H pylori compared to those given placebo.
Lead researcher Dr Alex Ford from the Centre for Digestive Diseases at Leeds General Infirmary said: 'You wouldn't have thought that treating H pylori infection would increase mortality risk. There are some deleterious effects of eradication therapy that we don't know about. It doesn't seem to cause any benefit in mortality over 10 years.'
He emphasised that the findings were the result of testing and treating non-symptomatic H pylori infection in the general population, and that H pylori eradication should remain the first-line option in the management of dyspepsia.
'The people we looked at were randomly selected members of the population who were invited to take part in a screening trial. GPs should still be testing and treating H pylori in their dyspepsia patients,' he said.
- Gut 2006;55:supl no.11;A26