Symptom Research on Chronic Cough: A Historical Perspective

1 May 2001 | Volume 134 Issue 9 Part 2 | Pages 809-814

This review provides a perspective on how research on the management of cough has evolved, looks at key methodologic lessons that have been learned from this research and how they may relate to the management of other symptoms, identifies important methodologic challenges that remain to be solved, and lists important questions that still need to be answered. Three important methodologic lessons have been learned. First, cough must be evaluated systematically and according to a neuroanatomic framework. Second, the response to specific therapy must be noted to determine the cause or causes of cough and to characterize the strengths and limitations of diagnostic testing. Third, multiple conditions can simultaneously cause cough. Among the three methodologic challenges that still need to be solved are 1) definitively determining the diagnostic accuracy and reliability of 24-hour esophageal pH monitoring and how best to interpret pH test results, 2) definitively determining the role of nonacid reflux in cough due to gastroesophageal reflux disease, and 3) developing reliable and reproducible subjective and objective methods with which to assess the efficacy of cough therapy. Numerous important clinical questions are still unanswered: What role do empirical therapeutic trials play in diagnosing the cause of chronic cough? What is the most cost-effective approach to the diagnosis and treatment of chronic cough: empirical therapeutic trials or laboratory testing–directed therapeutic trials? How often is environmental air pollution, unrelated to allergies or smoking, responsible for chronic cough?

Author and Article Information

From University of Massachusetts Medical School, Worcester, Massachusetts.
Note: This article is one of a series of articles comprising an Annals of Internal Medicine supplement entitled " Investigating Symptoms: Frontiers in Primary Care Research—Perspectives from The Seventh Regenstrief Conference " To see a complete list of the articles included in this supplement, please view its Table of Contents.

Requests for Single Reprints: Richard S. Irwin, MD, Division of Pulmonary, Allergy, and Critical Care Medicine, University of Massachusetts Medical School, 55 Lake Avenue North, Worcester, MA 01655; e-mail, irwinr{at}ummhc.org.

Current Author Addresses: Drs. Irwin and Madison: Division of Pulmonary, Allergy, and Critical Care Medicine, University of Massachusetts Medical School, 55 Lake Avenue North, Worcester, MA 01655.