Gastro-oesophageal reflux and nocturnal asthma.

Gastro-oesophageal (GO) reflux is believed to be a possible cause of nocturnal asthma. The aim of this study was to see if there is any correlation between the incidence of GO-reflux at night and nocturnal asthma. Thirty-seven adult patients with a history of nocturnal asthma for more than one hundred days a year and of reflux disease were evaluated using 24 h pH-monitoring of the oesophagus and measurement of peak expiratory flow (PEF) rate every hour when awake. Half of the patients suffered from severe GO-reflux at night, whilst the other half had no nocturnal reflux. Respiratory symptoms and inhalation of beta-2 agonists were recorded during the night and PEF was recorded when the patients awoke in the morning. A significant correlation was found between reflux at night and the degree of bronchial obstruction in the early morning, but not between night-time reflux and nocturnal respiratory symptoms. It would appear that GO-reflux in most asthmatics is neither a strong nor immediate trigger factor in nocturnal asthma, although it does seem to influence bronchial obstruction during the night as was demonstrated by a low morning-PEF value.