Laurie Slovarp, PhD, School of Speech, Language, Hearing, & Occupational Sciences, University of Montana

Marie Jette, PhD, Department of Otolaryngology – Head and Neck Surgery, University of Colorado Anschutz Medical Campus

Jane Reynolds, PhD, School of Speech, Language, Hearing, & Occupational Sciences, University of Montana

Amanda Gillespie, PhD, Department of Otolaryngology and Head and Neck Surgery, Emory University

Julie Barkmeier-Kraemer, PhD, Division of Otolaryngology – Head and Neck Surgery, University of Utah

Mary Sandage, PhD, Speech, Language, and Hearing Sciences, Auburn University

Jaclyn Smith, PhD, Biology, Medical and Health Sciences, The University of Manchester

Jemma Haines, BSc(Hons), Medical and Health Sciences, The University of Manchester, Manchester University NHS Foundation Trust

Anne Vertigan, PhD, School of Medicine and Public Health, University of Newcastle

Stuart Mazzone, PhD, Department of Anatomy and Physiology, University of Melbourne

Corresponding author: Laurie Slovarp, PhD,

Key words : pediatric chronic cough, habit cough, suggestion therapy, speech-language pathology

Funding : none

Conflicts of Interest: The authors declare no conflicts of interest.

Author Contributions :

Laurie Slovarp: conceptualization, writing original draft, review and editing

Marie Jette: conceptualization, writing original draft, review and editing

Jane Reynolds: conceptualization, writing original draft, review and editing

Amanda Gillespie: conceptualization, writing original draft, review and editing

Julie Barkmeier-Kraemer: review and editing

Mary Sandage: review and editing

Jaclyn Smith: review and editing

Jemma Haines: review and editing

Anne Vertigan: review and editing

Stuart Mazzone: writing, review, and editing

Abstract/Summary : This commentary responds to Weinberger and Buettner’s critique of Fujiki et al.’s study on behavioral cough suppression therapy (BCST) for pediatric chronic cough. While acknowledging their contributions, it addresses inaccuracies and clarifies key aspects of BCST. The commentary highlights discrepancies in terminology, challenges assertions regarding diagnostic evaluations, and emphasizes the need for controlled trials to assess treatment efficacy.

In their engagement with the study by Fujiki et al.¹, Weinberger and Buettner² bring attention to critical aspects of behavioral cough suppression therapy (BCST) and pediatric chronic cough treatment. While their contributions are valued, it is imperative to address certain inaccuracies and clarify key aspects of the study and BCST provided by specialized speech-language pathologists (SLPs).

Firstly, Weinberger & Buettner inaccurately state that Fujiki et al. identified the children as having ”behavioral cough.” The term ”behavioral cough” in the paper was used only in the context of ”behavioral cough suppression therapy,” describing the treatment rather than the children’s cough diagnosis. The authors, in fact, used the term ”nonspecific cough/tic cough” in accordance with current CHEST and ERS guidelines^3-5. Weinberger & Buettner’s assertion that ”historical evidence and current practice support “habit cough” as the appropriate diagnosis” lacks substantiation and contradicts contemporary CHEST guidelines⁵. We are particularly puzzled by Weinberger & Buettner’s advocacy for the term habit cough when Dr. Weinberger is listed as an author on a 2015 CHEST guidelines publication that explicitly advises against the use of these terms, deeming them ”out of date and inaccurate”⁵.

Weinberger & Buettner also criticize the use of extensive evaluations for the children in the sample, arguing that “habit cough” can be diagnosed based on clinical presentation alone—specifically in the presence of a barking or honking cough and absence of the cough during sleep. Interestingly, the same CHEST guidelines, of which Weinberger is an author, specifically cautions against using the diagnostic terms of “psychogenic” or “habit cough” solely based on a barking or honking sound or the absence of cough during sleep, stating that these three clinical presentations lack specificity⁵. A barking or honking cough can occur with other diseases such as tracheomalacia or bronchiectasis⁶; and it is well documented that sleep inhibits the cough reflex in adults even when an organic disease process is identified^{7; 8}. Without evidence to the contrary, it is should be assumed that sleep similarly suppresses cough in children. Further, the purpose of Fujiki et al.’s paper was to examine whether BCST improves cough in children and to describe cough characteristics and comorbidities, not to advocate for extensive assessments. Although, it is noteworthy that laryngoscopy revealed structural laryngeal pathology in several cases, challenging Weinberger & Buettner’s assertion that the described assessments were unjustified.

Regarding the treatment described in Fujiki et al., Weinberger & Buettner characterize BCST as an “alternative to suggestion therapy.” This overlooks that BCST instructs in strategies to suppress cough, akin to his “suggestion therapy.” Therefore, it seems that BCST is not necessarily an alternative but rather a similar therapy with a different name. This overlap emphasizes the need for clarity in terminology. Importantly, in adults with chronic cough a loss of centrally (brain) mediated cough suppression has been demonstrated using functional brain imaging⁹.  Although empirical data in children is not available, it seems conceivable that similar mechanisms may be in operation, providing a neurobiological basis for why cough suppression training is often beneficial and supporting the use of terminology that emphasizes this aspect of the therapy.

Additionally, Weinberger & Buettner’s argument that 45 pediatric pulmonologists ”already indicate they readily diagnose habit cough and successfully treat with suggestion therapy,” implies a stance against SLP treatment. However, considering there are thousands of pediatric pulmonologists in the U.S. alone, the sample size of 45 falls short of substantiating the claim that ”many” pulmonologists universally adopt this approach or that additional clinicians, such as SLPs, are unnecessary to assist these patients effectively. The argument lacks robust evidence and fails to account for the role of additional clinicians, such as SLPs, to address pediatric chronic cough effectively. Further, a substantial proportion of children in Fujiki et al.’s sample presented with phonotraumatic lesions (e.g., vocal nodules), which SLPs are specifically trained to address through behavioral treatment.

Lastly, Weinberger & Buettner suggest that conducting a controlled trial for suggestion therapy is impractical due to the reported low frequency of referrals. We disagree that the size of the population is a valid argument for not conducting a randomized controlled trial. A control group is needed to robustly assess the efficacy of any treatment, particularly in the case of cough interventions which are particularly vulnerable to placebo effect^{10; 11}. Weinberger & Buettner suggest that it would be unethical to withhold suggestion therapy for the sake of a randomized clinical trial; however, one could easily design a study that allowed for those randomized to a control treatment to be eligible for suggestion therapy upon completion of the control arm. Given Dr. Weinberger’s data suggests suggestion therapy eliminates nonspecific/tic cough in less than one week, such children would need to wait no more than one to two weeks before becoming eligible for suggestion therapy and it should be possible to demonstrate such a substantial effect in a relatively small number of subjects in a randomized controlled trial.

We agree with Dr. Weinberger that SLP skills vary. As is the case with any clinical discipline, there are many subspecialties in the field of speech-language pathology and varying levels of skill and expertise within those subspecialties. BCST training is not standard in SLP training programs, and, therefore, requires special training.

In conclusion, we think these clarifications underscore the importance of understanding Fujiki et al.’s paper in its correct context, and will advance a more nuanced and informed discussion on pediatric cough disorders and BCST’s role in treatment. We acknowledge Weinberger & Buettner’s contribution to pediatric cough management. The data reported in this letter and other publications^{12; 13}, although anecdotal, suggests that behavioral treatment focused on cough suppression is effective. Given this, we encourage Weinberger and Buettner to complete a randomized controlled efficacy trial. If the data confirms efficacy, the study would significantly elevate the legitimacy of the treatment, increasing its use by other practitioners and benefitting pediatric patients with chronic cough.

REFERENCES

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