Hoarseness. Around the same time as our data were presented, an article was published in Lancet in which researchers conducted a randomized, double-blind, placebo-controlled study of patients with idiopathic cough who were treated with gabapentin or placebo. Similar to our study, these investigators found significant improvement in their patients’ cough-related quality of life, with a number needed to treat of 4. However, in contrast to our study, these patients received higher doses of gabapentin with a different titration protocol up to 1,800 mg if tolerated, which led to a 31% rate of adverse effects.
Chronic coughing is a serious symptom of GERD and is very difficult to diagnose. Physicians are trained to consider GERD as the potential cause of chronic cough when other reasons cannot explain its presence. However, conventional medicine has no answer to this condition. This problem needs a holistic Functional Medicine approach whereby if a cough is present and no treatment is found effective, the underlying problem should be regarded as GERD. And the root cause of the problem should be treated. A Functional Medicine approach endeavors to correct the imbalance of the bodily functions that has caused a chronic condition.
RM Older studies of standard GERD therapy (PPIs) for patients with chronic cough were predominantly small observational studies. Some of these studies found that up to 70% of patients with chronic cough responded to PPIs. However, data from more recent randomized controlled trials suggest that PPIs for patients with chronic cough are not as effective as we initially believed. The most recent review from the Cochrane group found a lack of strong data supporting the practice of empiric this PPI therapy for patients with chronic cough. The subgroup of patients who may respond best to PPIs are those with concomitant GERD symptoms such as heartburn and regurgitation or a positive pH study, but even within this subgroup, only approximately one third of patients will respond to PPIs. In one study of patients with chronic idiopathic cough and no heartburn, there was no difference in outcomes between the group that received high-dose PPIs and the group that received placebo.
RM Two mechanisms have been proposed to explain why people with GERD develop chronic cough. The most intuitive theory is called the reflux theory, whereby reflux rises above the esophagus and upper esophageal sphincter, resulting in microaspiration as microdroplets land in the larynx or occasionally enter the bronchial tree, directly causing cough as a protective mechanism against reflux. The other theory is known as the reflex theory. Because of the common embryologic origin of the respiratory tract and the digestive tract, a little bit of reflux in the esophagus can lead to an esophagobronchial reflex that causes cough.