Gastro-oesophageal reflux prevalence and relationship with bronchial reactivity in asthma

The relationship between asthma and gastro-oesophageal reflux (GER) is controversial. In an allergy department, GER prevalence was evaluated in asthmatics, with a view to judging the potential influence of GER on asthma. One hundred and five asthmatics were recruited and co-investigated for GER and lung function. Descriptive analysis was performed, patients with (GER+) and without (GER-) GER were then compared, and finally, stepwise regression analysis was used. GER prevalence was 32%. Lung parameters did not differ between GER+ and GER- patients. When restricting analysis to GER+ patients, bronchial reactivity was closely correlated to the number of reflux episodes (NRE) (r=0.983; p=0.001). When comparing patients with more than 15 reflux episodes x day(-1) (n=50), with those having less (n=43), no differences were found in lung function and GER parameters. However, there was a positive correlation between the provocative dose of methacholine causing forced expiration volume to fall 20% from the baseline and NRE in patients with NRE>15 (r=0.561; p=0.05). In conclusion, gastro-oesophageal reflux was observed in a third of the asthma patients studied. These data do not support a firm aetiological relationship between gastro-oesophageal reflux and asthma, but do suggest an association between the number of reflux episodes and bronchial hyperresponsiveness.