Guideline Updates for Chronic Cough Kick Off American Cough Conference

Chronic cough is a condition that lasts for 8 weeks or longer in adults or 4 weeks or longer in children, and there are now updated guidelines for the diagnosis and management of cough, even though there are few therapies approved.

During the opening session at the American Cough Conference, Alyn Morice, MD, FRCP, head of respiratory medicine at Hull York Medical School at the University of Hull, and Anne B. Chang, MBBS, FRACP, PhD, associate professor at Queensland University of Technology and head of the Child Health Division at Menzies School of Health Research, presented updates to the guidelines for chronic cough in adults and children.^1,2

The challenge with developing guidelines for chronic cough is that “there is little literature in cough. So, we have a very small database on which to compare things,” Morice said.

As a result, the guideline task force could not recommend doing a chest x-ray in someone with chronic cough because there are no randomized controlled trials that show a chest x-ray is needed to screen that patient.

Chronic cough is due to a hypersensitivity of the cough reflex, Morice explained. Furthermore, it has been shown that women are particularly sensitive.

“So, this explains the preponderance of women in in our cough clinics, because they have a higher central response to a given stimulus,” he said. Morice added that approximately two-thirds of patients with cough are women.

He described chronic cough as being unlike any other chest disease and that it is not well described. People who aren’t knowledge about it are likely to dismiss chronic cough as “just a cough.” But it is more than that because of how severe and disruptive it can be. Morice has had patients on the phone with him, crying “because they want to have relief of this chronic problem that they've had for 10 years, and everybody else has been either ignoring them or saying, ‘You've got to live with that.’ And it ruins lives. Particularly with the ladies.”

The guidelines recommend that physician in the clinic do a simple score of the cough out of 10. Each time a patient goes to the clinic, their cough is scored so any improvement can be seen in a simple way.

Morice also addressed the name of the condition, which has caused some confusion about chronic cough. It has gone by many names:

• Chronic cough or idiopathic cough, cough hypersensitivity syndrome, unexplained chronic cough, refractory chronic cough, laryngeal hypersensitivity, laryngeal paresthesia, hypertussia, allotussia chronic obstructive pulmonary disease, or bronchiectasis
• Asthmatic cough, or atopic cough, cough variant asthma, eosinophilic bronchitis, or reactive airways syndromes
• Reflux cough or gastroesophagel reflux, laryngo-pharageal reflux, airway reflux, aspiration, or vocal cord dysfunction
• Postnasal drip syndrome or upper airways cough syndrome, rhinitis, or sinusitis

“Some people undoubtedly have a rhinitis or sinusitis, but is it a separate disease?” he asked. “Because the demographics are the same.”

Morice advocated for calling it refractory chronic cough, or RCC. He admits that may be a confusing diagnosis when drugs are approved in the future to treat chronic cough: without having been treated by any drugs approved for it, the cough isn’t really refractory. But RCC does indicate that the condition has unsuccessfully been treated by the conventional treatments currently available.

“We’ve got to have a name for it, though, because we’ve got to communicate with people who are ignorant about cough and what it is,” he said.

Chronic cough isn’t exactly the same in children as it is in adults, which necessitates separate guidelines, explained Chang. Originally, children and adults were part of the same guidelines, but in 2006, children were separated out.

Pediatric guidelines are important because it helps to promote awareness of cough in children; it can help improve diagnosis, management, and care; earlier diagnosis and optimal management improves quality of life and outcomes; and children are different than adults.

As in other diseases, children cannot be treated as just smaller people. For instance, the underlying etiologies of cough are different in children, the definition of chronic cough is 4 weeks in children vs 8 weeks in adults, and there are pediatric-specific outcomes measures, Chang explained.

In the previous guidelines, only 2 of 13 recommendations had good evidence, but now 16 of 40 are grade 1.

One of the recommendations was not using treatments for gastroesophageal reflux disease (GERD) in children 14 years and younger with chronic cough. According to Chang, there is hardly any evidence on using GERD treatments for cough. If the child does have gastroesophageal reflux symptoms, they can be treated for GERD for 4 to 8 weeks, but this recommendation is ungraded because there really is no evidence.

“We really suggest that they get properly investigated if you really need to treat them,” she said.

One area of change that was controversial was on habit and somatic cough. The guidelines have 10 recommendations, with 9 related to diagnosis and only 1 related to management. In addition, all of the recommendations were grade 2 or consensus based, which showed there was a lack of evidence and studies.

“And so, I'm just going to mention that is quite controversial,” Chang said.

She also highlighted the numerous names used for chronic cough over the years, such as habit cough, tic cough, psychogenic cough, and honking cough. The new guidelines now recommend against using habit cough and psychogenic cough. Habit cough has been swapped for tic and psychogenic cough has been swapped for somatic cough.

“The updated guidelines, compared to the previous [guidelines], really has got better processes … there's definitely a lot more evidence…[and] we have covered more topics,” she concluded.

References

1. Morice AH, Millqvist E, Bieksiene K, et al. ERS guidelines on the diagnosis and treatment of chronic cough in adults and children. Eur Respir J. 2020;55(1):1901136. doi:10.1183/13993003.01136-2019

2. Chang AB, Oppenheimer JJ, Irwin RS, CHEST Expert Cough Panel. Managing chronic cough as a symptom in children and management algorithms: CHEST guideline and expert panel report. Chest. 2020;158(1):303-329. doi:10.1016/j.chest.2020.01.042