The severity and incidence of asthma have increased drastically in the developed nations of the world over the last decades.
Currently, some evidences indicate an inverse association between Helicobacter pylori and asthma, but some studies did not get the same conclusion.
Dr Qiang Wang and colleagues from China systematically reviewed the published evidence for an association between H. pylori infection and asthma."
Medline and SCI databases up to 2012 were searched to identify studies that evaluated the association between H. pylori and asthma.
|19 studies met the inclusion criteria|
The research team evaluated that the relevant publications were searched using the following keywords or synonyms: asthma or Helicobacter pylori.
Methodologic quality was scored by using a standardized list of criteria, and meta-analysis was conducted to calculate crude odds ratios with 95% confidence intervals.
The research team identified 19 studies that met the inclusion criteria.
The team identified 9 cross-sectional studies, 7 case–control studies, and 3 prospective cohort studies.
The overall methodologic quality score was high.
Pooled odds ratios for the association between asthma and H. pylori infection were 0.8 in 9 cross-sectional studies, 0.9 in 7 case–control studies, and 0.8 in 3 cohort studies.
The team found that pooled odds ratios for all included studies was 0.81 in children, and 0.88 in adults.
Dr Hubei's team concluded, "We found a weak evidence for an inverse association between asthma and H. pylori infection both in children and in adults."