Multidisciplinary Clinic Studies Chronic Cough

Cough is one of the leading causes of physician visits annually. Chronic cough lasting longer than eight weeks is a perplexing condition of the airway that the medical community is still attempting to comprehend and effectively treat.

Chronic cough is linked to increased morbidity and lower quality of life and it requires further investigation. In 2016, it became recognized as a distinct condition called unexplained chronic cough (UCC) by the American College of Chest Physicians. As there is no consensus on terminology, other diagnoses may include cough hypersensitivity syndrome, chronic refractory cough, sensory neuropathic cough, and post-viral neurogenic cough.

UCC is typically a diagnosis of exclusion after workup and empiric treatment for reflux, allergy and pulmonary conditions fail to resolve the cough. To help patients who have run the gamut in seeking help for UCC, Cleveland Clinic has created the Chronic Cough Clinic with a multidisciplinary team of physicians available to provide patients with a full diagnostic work up to determine the source of a nagging cough.

The clinic, launched in June 2016 and co-directed by otolaryngologist Paul C. Bryson, MD, and pulmonologist Rachel Taliercio, DO, includes experts from Cleveland Clinic’s Head & Neck Institute, Respiratory Institute and Digestive Disease & Surgery Institute. Clinic staff offer comprehensive pulmonary function testing and upper airway evaluation, including the sinuses and the larynx. And when needed, patients have access to gastrointestinal testing, including acid reflux testing, behavioral cough suppression with speech therapy, and allergy testing.

“This is a unique offering for patients that provides a comprehensive examination of all potential causes of chronic cough,” says Dr. Bryson. “We’ve found this an efficient and effective way to help patients who are often dealing with this long-term, quality of life reducing problem without any relief.”

Dr. Taliercio says, “Many patients with chronic cough have been dealing with the condition for years and sometimes decades. We have developed a systematic, interdisciplinary approach to diagnosis and management of chronic cough.”

Study takes a closer look

In an effort to get to a better understanding of successful treatments for UCC, Dr. Bryson and Dr. Taliercio conducted a single institute retrospective analysis of UCC patients. Although off-label use of neuromodulators are known to be effective for some patients with chronic cough, Dr. Bryson says few studies have used validated measurements to assess their efficacy during treatment and to describe the patient experience. The Leicester Cough Questionnaire (LCQ) is currently the only validated outcome measurement for chronic cough.

Patients who presented to Cleveland Clinic’s Chronic Cough Clinic and were diagnosed with UCC were placed on neuromodulator therapy. LCQ scores were obtained during the initial visit and again after two months of neuromodulator treatment.

A total of 26 patients had data available following two months of treatment with neuromodulators. Fifteen patients were placed on gabapentin, while 11 patients were placed on a tricyclic antidepressant (amitriptyline or nortriptyline). Patients on gabapentin demonstrated an average improvement of 2.97 points on the LCQ scale, while patients on a tricyclic antidepressant improved by 4.68 points. Both treatments resulted in a statistically significant improvement when compared with baseline LCQ measurements (Wilcoxon signed-rank tests, gabapentin, P = 0.015; tricyclic antidepressants, P = 0.014).

“Short-term results demonstrate that gabapentin and amitriptyline are both effective at treating UCC,” says Dr. Bryson. “Longer term, prospective data and patient experience is ongoing.”

The study is also describing other phenomenon in this patient population, including patient’s ability to wean off of medication as well as describe tachyphylaxis to neuromodulators in this group. Tachyphylaxis is the rapid loss of effectiveness of neuromodulators that were initially efficacious for chronic cough.

The multidisciplinary clinic also offers specialized treatment for appropriately selected patients to receive behavioral cough suppression therapy and laryngeal botox injections.