[Risk factors for gastroesophageal reflux in chronic asthma]

In order to study risk factors for gastroesophageal reflux (RGO), we have analysed the clinical particulars, the spirometry and the different therapies of chronic asthmatics with and without RGO. RGO has been studied using 24 hour pH manometry in 53 patients suffering from chronic asthma. 70% of these patients had RGO, defined as oesophageal pH below 4, for 4.2% or more of the total time. The only predictive factor for the presence of RGO (log regression) was the dose of theophylline (P is equal to 0.02) whose average dose was higher in cases of RGO (9.1 plus or minus 2.3 mg/kg against 6.3 plus or minus 1.7 mg/kg, P is less than 0.03). Although the severity of the asthma and the spirometric parameters were similar. On the other hand, the severity of RGO, assessed as the percentage of the total time passed with a pH below 4 or correlated (multiple regression) with longevity of the disease (P is equal to 0.02) and the dose of theophylline (P is equal to 0.001). These results suggest that the treatment with theophylline and the duration of the asthma could constitute risk factors for RGO in chronic asthma.