Lower esophageal sphincter pressures in patients of bronchial asthma and its correlation with spirometric parameters: a case-control study

Abstract

Objectives: The cause–effect relationship between bronchial asthma and gastro-esophageal reflux (GER) is known, but studies have not been able to confirm the improvement of lung function with anti-acid therapy. Hypotensive lower esophageal sphincter (LES) may lead to both acid and non-acid reflux, resulting in asthma symptoms and decreased lung function. The objectives of our study were, firstly, to compare basal LES pressure between adult patients of asthma and normal controls and, secondly, to correlate the basal LES pressure with spirometric parameters in these patients. Methods: Thirty patients, aged between 18 and 65 years, diagnosed as cases of bronchial asthma and 27 healthy controls were included in the study. All the participants were subjected to esophageal manometry after overnight fasting and basal LES pressures were recorded. Then, spirometry was done 2 h after meal and pre- and post-bronchodilator FEV1, FVC, PEFR were obtained for the asthma group. Results and conclusions: There is significant difference between basal LES pressure in patients of bronchial asthma and control population (8.70 ± 2.67 mmHg versus 16.64 ± 5.52, p < 0.0001). 66.67% of the asthma patients have reduced LES pressures (<10 mmHg). The correlation coefficient between basal LES pressure and prebronchodilator FEV1% predicted is 0.596 (p < 0.0001, 95% CI 0.3002–0.7872). Obstructive airway impairment in adult patients of bronchial asthma is associated with hypotensive LES. GER, due to hypotensive LES may contribute to deterioration of spirometric parameters in asthma patients.