Chronic Cough Due to Gastroesophageal Reflux Disease: Surgery
Irwin et al, in a small, prospective, before-and-after intervention trial in patients with chronic cough who had failed to respond to very intensive medical therapy, reported the improvement or elimination of cough in all subjects 12 months following surgery. In this study, cough persisted prior to surgery even though the antireflux medical regimen was serially intensified until there was total or near-total elimination of esophageal acid on repeated 24-h esophageal pH monitoring. This finding supported the diagnosis of nonacid reflux disease.
The results of a metaanalysis of 15 trials (open-label, 2 trials; randomized, controlled, 10 trials; randomized, controlled, crossover, 3 trials) that did not involve extraesophageal symptoms such as cough showed that the short-term treatment (ie, 1 to 4 weeks) of GERD with normal-dose or high-dose proton pump inhibition (ie, the so-called PPI test) in patients who were suspected of having GERD did not confidently establish or exclude the diagnosis when GERD was defined by objective reference standards. In patients with GI symptoms suggestive of GERD in which the clinical response to a short course of proton pump inhibition was compared with 24-h esophageal pH monitoring, the positive likelihood of a symptomatic response detecting GERD ranged from 1.63 to 1.87. The sensitivity was 0.78 (95% confidence interval, 0.66 to 0.86) and specificity 0.54 (95% confidence interval, 0.44 to 0.65). canadian family pharmacy
While Ours et al concluded from their prospective, double-blind, randomized, placebo-controlled study that the best diagnostic and therapeutic approach to chronic cough is a fixed dose of omeprazole, 40 mg bid for 2 weeks, there are many methodological concerns about this study that make the results uninterpretable. With respect to concerns about GERD, there were 17 patients with chronic cough who had abnormal findings of 24-h esophageal pH-monitoring studies, and only 6 patients improved with omeprazole therapy for a response rate of 35%. Because the authors assumed that the dose and duration of omeprazole therapy that they used would cure all patients with cough due to GERD, they reasoned that the other patients with abnormal findings of 24-h esophageal pH-monitoring studies could not have GERD. In the patients who did not respond, the authors did not (1) determine whether their medical therapy was maximal, (2) consider that their subjects might have had nonacid reflux disease and therefore required more than acid suppression therapy, and (3) did not find another cause for the chronic coughs of the patients.