Researchers have investigated the response rate of acid suppression treatment in patients with chronic coughs to see which factors predicted likelihood of success of treatment.
Gastro-oesophageal reflux disease is believed to play an important role in chronic cough and patients are often empirically treated with acid suppression therapy.
Acid suppressing therapy includes proton pump inhibitors (PPIs) – such as Omeprazole – and H2 antagonists like Ranitidine.
In a new study, recently published in the medical journal Lung, researchers monitored 320 patients attending two specialist cough clinics – one in the UK and one in the US.
Their study found that only 72 patients had heartburn. Of those 72, 28 per cent noted improvement in their cough with acid suppression, whereas of 248 without heartburn, only 14 per cent responded. Patients reporting heartburn were 2.7 times more likely to respond to acid suppression therapy.
These findings indicate that heartburn is the only significant predictor of success of acid suppression therapy when treating chronic cough in a ‘real-life’ setting.
The researchers also say that their data suggests that acid suppression is unlikely to be successful in the majority of patients with chronic cough.
One possible explanation given for the low numbers of responders to acid suppression is that these therapies only suppress the acidity of the refluxate and have no effect on non-acid reflux or the number of reflux events.
The paper Heartburn as a Marker of the Success of Acid Suppression Therapy in Chronic Cough suggests that in order to explore this further, trials in chronic cough patients using therapies that target lower oesophageal sphincter relaxations and reducing non-acid and acid reflux are needed.
Professor Alyn Morice, head of the Hull Cough Clinic, commented: “This study confirms that the symptoms of acid reflux, heartburn and acid regurgitation are an important indicator for the use of acid suppression treatment in chronic cough.
“Most patients with chronic cough, however, do not have peptic symptoms and should not be given anti-acid treatment. They suffer from non-acid reflux which is a gaseous mist that I call airway reflux. This needs to be treated with drugs which work on oesophageal motility rather than giving potentially harmful drugs such as proton pump inhibitors, which is currently the case.”