The association of body mass index and gastroesophageal reflux disease (GERD) is unclear.
There is also uncertainty about the association between body mass index and GERD complications such as esophagitis, Barrett esophagus, and esophageal adenocarcinoma.
Dr Hashem El-Serag and colleagues from Texas conducted a systematic review and meta-analysis to evaluate this association.
The magnitude of an association between obesity and GERD, erosive esophagitis, Barrett esophagus, and adenocarcinoma of the esophagus and of the gastric cardia was estimated.
The research team searched MEDLINE between 1966 and 2004 for published full studies.
The researchers included studies that provided risk estimates and met criteria on defining exposure and reporting outcomes and sample size.
Data was extracted by 2 researchers independently performing a standardized search.
|Odds ratio for GERD symptoms was 1.9 for body mass index greater than 30 kg/m2|
|Annals of Internal Medicine|
The team obtained unadjusted and adjusted odds ratios for individual outcomes or calculated for each study and were pooled by using a random-effects model.
The researchers found that 9 studies examined the association of body mass index with GERD symptoms.
The team noted that 6 of these studies found statistically significant associations.
The researchers also noted that 6 of 7 studies found significant associations of body mass index with erosive esophagitis, and esophageal adenocarcinoma.
A significant association with gastric cardia adenocarcinoma was found in 4 out of 6 studies.
In data from 8 studies, the team found a trend toward a dose-response relationship.
There was an increase in the pooled adjusted odds ratio for GERD symptoms of 1.4 for a body mass index of 25 kg/m2 to 30 kg/m2.
The team observed that the pooled adjusted odds ratio for GERD symptoms was 1.9 for body mass index greater than 30 kg/m2.
Similarly, the pooled adjusted odds ratio for esophageal adenocarcinoma for a body mass index of 25 kg/m2 to 30 kg/m2 was 1.5.
The researchers found that with a body mass index greater than 30 kg/m2, the pooled adjusted odds ratio for esophageal adenocarcinoma was 2.8.
The team noted heterogeneity in the findings, although it was mostly in the magnitude of statistically significant positive associations.
In addition, the researchers reported that no studies in this review examined the association between Barrett esophagus and obesity.
Dr El-Serag's team concludes, “Obesity is associated with a statistically significant increase in the risk for GERD symptoms, erosive esophagitis, and esophageal adenocarcinoma.”
“The risk for these disorders seems to progressively increase with increasing weight.”