Reference | Country | Study design | Patient recruitment | Sampling frame | Prevalence of hiatal hernia in patients with asthma | Prevalence of erosive oesophagitis in patients with asthma | Prevalence of Barrett’s oesophagus in patients with asthma | Prevalence of erosive oesophagitis in controls | Prevalence of hiatal hernia in controls | Unadjusted odds ratio/relative risk (95% CI) |
Kjellen et al 198169 | Sweden | Cross-sectional | Consecutive | Secondary care, asthma clinic | 36/97 (37.1%) | – | – | – | – | – |
Sontag et al 199232 | USA | Cross-sectional | Consecutive | Secondary care, asthma clinic | 97/186 (52.2%) | 73/186 (39.2%) | 24/186 (12.9%) | – | – | – |
Carmona-Sanchez et al 199928 | Mexico | Cross-sectional | Consecutive | Secondary care, asthma clinic | 37/60 (61.7%) | – | – | – | 61/180 (33.9%)∗ | RR 3.13 (1.64 to 6.01) |
Avidan et al 200131 | USA | Cross-sectional | Consecutive | Secondary care, asthma clinic | 71/128 (55.5%) | 43/128 (33.6%) | – | – | – | – |
Nakase et al 199940 | Japan | Cross-sectional | Consecutive | Secondary care | – | 20†/72 (27.8%) | – | – | – | – |
Shimizu et al 200636 | Japan | Cross-sectional | Consecutive | Secondary care, asthma clinic | – | 37/78 (47.4%) | – | 6/150 (4.0%)‡ | – | OR 21.7 (8.5 to 54.9)† |
CI, Confidence interval; OR, odds ratio; RR, relative risk.
∗Controls were patients with dyspeptic symptoms, including heartburn and/or acid regurgitation, but without oesophagitis or previous gastric surgery.
†Calculated based on values given in publication.
‡Controls were outpatients who had visited the hospital for a routine health examination.