Nonpharmacological interventions for refractory chronic cough patients: systematic review

[Specialist Guidelines of The German Respiratory Society for Diagnosis and Treatment of adult Patients Suffering from Cough]

This is the 4th edition of the Cough Guidelines of the German Respiratory Society written by respiratory, gastroenterology, ear-nose-throat specialists, including respiratory physiotherapists and speech pathology specialists; importantly, a patient representative was also involved.Compared with earlier versions we used a new methodology: after discussion in the guidelines group, we asked and answered the 12 most important and most frequent "key" questions regarding the clinical practice. The extent of the guideline could thus be significantly reduced.We added a short scientific background to each of the answers including the most recent references. The recommendations and statements were created in consensus and graded as strong, or weak. If sufficient literature was not available, we suggested discussing joint decisions with the patient.The 12 key questions are as follows:- Key question 1: The classification of cough (acute, i. e. up to three weeks duration; chronic, i. e. after 8 weeks duration and subacute in between) did not change, but we added "cough with or without expectoration as an additional classification aspect with therapeutic consequences.- Key question 2: Acute and subacute cough are mostly (but not exclusively) due to the common cold. They are the first or second most frequent symptom prompting patients to seek medical (or pharmacist's) care. Antibiotic therapy is strongly discouraged for common cold- Key question 3: We defined "Red flags" for mandatory immediate diagnostic for acute cough, which usually does not require such diagnostic procedures- Key question 4: Chronic cough overview of the most common causes for- Key question 5: Cough in acute SARS-CoV-2 infection and in long COVID - Key question 6: Refractory chronic cough and idiopathic chronic cough, two recently established entities were explained more in detail- Key question 7: To upper airway cough syndrome - Key question 8: Gastro-oesophageal-reflux-related cough - Key question 9: Cough-variant asthma and non-asthmatic eosinophilic bronchitis - Key question 10: Overview of drugs causing cough - Key question 11: Basic and personalized (due to the individual history) diagnostic procedures for patients with cough- Key question 12: Physiotherapy, speech therapy and pharmacotherapy for cough.

Reframing Refractory Chronic Cough: The Role of Interoception

Refractory chronic cough (RCC) remains a persistent clinical challenge, often resistant to traditional treatments. Emerging evidence now positions RCC as a disorder rooted in hypersensitivity, driven primarily by central neural processes rather than external physiological causes. Central to this understanding is the concept of interoception-the brain's ability to perceive and interpret internal bodily signals. Neuroimaging research has identified abnormalities in brain regions associated with interoception and inhibitory control among RCC patients. Interestingly, RCC shares neurophysiological characteristics with other disorders like overactive bladder and urinary urge incontinence (OAB/UUI), which also involve dysregulated interoceptive and inhibitory mechanisms. Behavioral treatments for OAB/UUI are highly effective and are regarded as the first-line treatment in many consensus guidelines. OAB/UUI behavioral treatments have been shown to induce central neuroplastic changes, further underscoring their efficacy and potential parallel for RCC interventions. Behavioral cough suppression therapy (BCST), an efficacious treatment for RCC, may leverage similar neuroplastic adaptations, enhancing interoceptive processing and inhibitory control. Given the multi-dimensional nature of interoception, which encompasses sensory perception shaped by learning, memory, and emotional context, BCST's engagement of multiple neural pathways offers an alternative therapeutic option compared to single-mechanism pharmacological treatments. Future research should prioritize exploring the mechanistic underpinnings of BCST and other interoception-based therapies for developing more comprehensive and effective treatment options. Such research holds promise for improving patient outcomes, alleviating the significant healthcare burden associated with RCC, and advancing our understanding of central hypersensitivity disorders.

Efficacy and tolerability of SEDIFLÙ in treating dry or productive cough in the pediatric population (SEPEDIA): A pilot, randomized, double-blind, placebo-controlled, multicenter clinical trial

The aim of this trial was to assess the effectiveness of Sediflù, a medical device containing active herbal ingredients, on nocturnal and diurnal persistent coughs in children, with a duration of 3 to 7 days. Children with a dry and/or productive cough were enrolled in this prospective, interventional, multicenter, placebo-controlled, double-blind, randomized clinical study. Clinical efficacy was assessed through the evaluation of the soothing action of Sediflù against dry and/or productive coughing, both at night and during the day, and other effects of coughing associated with quality of sleep: frequency, child's quality of sleep, parental quality of sleep and severity. Treatment with Sediflù improved both night-time and day-time cough scores from day 2. The diurnal score also improved significantly in the Sediflù group at days 3 and 7. Sediflù syrup can be considered a valid treatment for cough management in younger children with upper respiratory tract infections, shortening the cough duration.

Prevalence of refractory and unexplained chronic cough in adults treated in cough centre

Background

Refractory chronic cough and unexplained chronic cough pose significant clinical challenges, impairing patients' quality of life. However, a precise definition of refractory chronic cough remains elusive. This study aimed to assess the prevalence of refractory and unexplained chronic cough among patients referred to our cough centre and to analyse the prevalence of refractory chronic cough relative to its definition.

Methods

This prospective cohort study included all patients who were diagnosed at a cough clinic between 2018 and 2022. The response to therapy was measured based on reduction in cough severity (via a visual analogue scale) and improvement in cough-related quality of life (via the Leicester Cough Questionnaire). Refractory chronic cough was defined as persistent cough severity, with no or minimal improvement (change in visual analogue scale <30 mm) after two or more treatment attempts and cough severity ≥40 out of 100 mm on the visual analogue scale.

Results

Of 201 patients treated for chronic cough, only three (1.5%) were diagnosed with unexplained chronic cough. Among 166 patients monitored for therapy response, 71 (42.8%) experienced a cough severity reduction of ≥30 mm on the visual analogue scale, while 100 (60.2%) showed an improvement of ≥1.5 points on the Leicester Cough Questionnaire. Based on the basic refractory chronic cough definition, 51 of 166 patients (30.7%) were diagnosed with refractory chronic cough. If applying stricter criteria (persistent severe cough (≥40 mm on the visual analogue scale), insufficient therapy response (<30 mm reduction on the visual analogue scale) and <1.5-point improvement on the Leicester Cough Questionnaire), 45 of 166 patients (27.1%) would be diagnosed with refractory chronic cough.

Conclusions

Refractory chronic cough is common in patients referred to cough clinics. The prevalence of refractory chronic cough differs slightly depending on the diagnostic criteria. Therefore, the definition of refractory chronic cough used in routine practice needs to be clarified.

Awareness and practices of Speech Language Pathologists (SLPs) working with chronic cough in India: a call for action

OBJECTIVE

A cough persisting beyond eight weeks is referred as chronic cough (CC) and is a common symptom of many respiratory conditions and non-respiratory conditions. The role of a speech language pathologist (SLP) in CC is emerging and this study aimed to profile the awareness and practice patterns of SLPs practicing in India.

STUDY DESIGN

Cross-sectional study.

METHOD

An online survey was used to profile the assessment, treatment and counselling practices in CC among SLPs working in India. It sought to identify the awareness levels among SLPs regarding their role and availability of behavioural interventions for CC. Only SLPs who dealt with CC could complete the entire survey while other SLPs, filled regarding awareness and availability of behavioural interventions.

RESULTS

127 eligible responses obtained from SLPs working across clinical settings in India were analysed. 75.59% (n=96) of them had not seen patients with CC in their career. 47.24% (n=60) of them were aware that behavioural interventions were available for CC. Thirty-one SLPs completed the entire survey and their practice patterns indicated that few clinicians used cough-specific protocols while largely relying on voice and swallowing related assessment and treatment for CC.

CONCLUSION

This survey the lack of awareness of SLPs' role in CC and that their practices are dominated by existing procedures for voice and swallowing disorders. Increasing the awareness of SLP's role in CC may increase the caseload of patients referred and expand the SLP's scope of practice. Development of guidelines in CC practice and inclusion in coursework/curriculum are future considerations.

Chronic Cough: Evaluation of Patients' Motivation to Undergo Cough Suppression Therapy

INTRODUCTION

Chronic cough is a persistent cough lasting greater than eight weeks. The prevalence rate is estimated to be 9% to 33% in the United States. There are several treatment modalities described in current literature including medical, surgical, and behavioral interventions. Behavioral intervention with a speech-language pathologist (SLP) includes education on laryngeal hygiene and the voluntary control of cough as well as respiratory retraining to suppress or reduce the duration of cough. Cough suppression therapy, like other behavioral therapies, requires patient motivation and commitment to participation and completion in therapy.

METHODS

This study was a prospective cross-sectional survey at a single academic institution. Adult patients evaluated by a laryngologist for chronic cough regardless of their primary etiology were included. Patients who were tracheostomy dependent, on oxygen therapy, had vocal fold paralysis/immobility, or had undergone previous laryngeal surgery were excluded. Patients were surveyed at the end of the initial clinic visit or at the beginning of the first cough suppression therapy session. Subjects reported their motivational factors for undergoing cough suppression therapy.

RESULTS

The majority of patients, 21 (58.33%), identified as female, 15 patients (41.20%) identified as male, and no patients identified as transgender, nonbinary, and/or other gender. The patients in this study had a mean age of 57.75 (12.12) years. 35 patients (97.22%) were interested in cough suppression therapy. The mean presenting cough severity index (CSI) was 19.39 (10.28) with the mean cough duration of 8.69 (12.10) years.

CONCLUSIONS

Patients primarily sought cough suppression therapy due to intrinsic factors rather than extrinsic influence. By understanding the relationship between symptomatology and patient motivation, clinicians can better counsel their patients and improve methods to assess candidacy for behavioral treatment.

[Chronic cough in adult patients-evidence-based approach]

Approximately 10% of the population suffer from a cough lasting longer than 8 weeks. Compared to acute cough, which usually occurs in the context of banal respiratory tract infections, the differential diagnoses of chronic cough require an increased use of diagnostic tests and thus a structured, evidence-based approach according to current international guidelines. A targeted history (smoking status, medication, previous diseases) and ENT status are always followed by chest x‑ray and pulmonary function tests before extended diagnostics. In the case of angiotensin-converting enzyme (ACE) inhibitor use and unremarkable physical examination, a drug discontinuation test can be carried out first. In case of inconspicuous findings, a disease entity that can be treated empirically such as upper airway cough syndrome is most likely. If the cough remains unexplained, cough suppression techniques, physiotherapy or speech therapy should be sought before off-label-use of medication.

Respiratory distress symptom intervention for non-pharmacological management of the lung cancer breathlessness-cough-fatigue symptom cluster: randomised controlled trial

OBJECTIVES

In lung cancer, three prominent symptoms, such as breathlessness, cough and fatigue, are closely related with each other forming a 'respiratory distress symptom cluster'. The aim of this study was to determine the clinical and cost-effectiveness of the respiratory distress symptom intervention (RDSI) for the management of this symptom cluster in people with lung cancer.

METHODS

A single blind, pragmatic, randomised controlled trial conducted in eight centres in England, UK. A total of 263 patients with lung cancer were randomised, including 132 who received RDSI and 131 who received standard care. To be eligible, participants self-reported adverse impact in daily life from at least two of the three symptoms, in any combination. Outcomes were change at 12 weeks for each symptom within the cluster, including Dyspnoea-12 (D-12), Manchester Cough in Lung Cancer (MCLC) and Functional Assessment of Chronic Illness-Fatigue.

RESULTS

At baseline, nearly 60% of participants reported all three symptoms. At trial completion the total trial attrition was 109 (41.4%). Compared with the control group, the RDSI group demonstrated a statistically significant improvement in D-12 (p=0.007) and MCLC (p<0.001). The minimal clinically important difference MCID) was achieved for each outcome: D-12 -4.13 (MCID >3), MCLC -5.49 (MCID >3) and FACIT-F 4.91 (MCID >4).

CONCLUSION

RDSI is a clinically effective, low-risk intervention to support the management of the respiratory distress symptom cluster in lung cancer. However, the study did experience high attrition, which needs to be taken onto consideration when interpreting these results.

TRIAL REGISTRATION NUMBER

NCT03223805.

Prevalence of Anxiety as a Variable in Treatment Outcomes for Individuals With Chronic Refractory Cough

PURPOSE

Anxiety is a mental state characterized by an intense sense of tension, worry, or apprehension relative to something adverse that might happen in the future. Anxiety is a known comorbidity in cough patients, yet its prevalence among those with chronic refractory cough (CRC) is unknown. Anxiety is not typically assessed during evaluation for CRC, but treatments for CRC such as neuromodulators and behavioral cough suppression therapy (BCST) may potentially attenuate anxiety. This preliminary study investigates the potential prevalence of anxiety in CRC and its possible role in treatment outcomes.

METHOD

CRC patients seen in a specialty clinic at the University of Utah or the University of Montana completed the Leicester Cough Questionnaire (LCQ) pre- and post-BCST treatment. Participants were dichotomized into positive anxiety screen (PAS) and negative anxiety screen (NAS) groups based on presence or absence of documented anxiety within electronic medical records at the University of Utah and based on a Generalized Anxiety Disorder-7 score > 5 at the University of Montana.

RESULTS

Of the 86 total participants, 37 (43%) were in the PAS group (29 females, Mage = 56 ± 13) and 49 (57%) were in the NAS group (36 females, Mage = 64 ± 14). Eighty-nine percent of CRC participants with a PAS reported a clinically meaningful improvement in LCQ total score following treatment compared to 65% of NAS participants. Furthermore, mean pre- to posttreatment change scores on the LCQ were significantly greater within the PAS group (p = .002, Cohen's d = 0.7, indicating a moderate to large effect size).

CONCLUSION

This preliminary study suggests that (a) anxiety may be prevalent among those with CRC and (b) those patients who screen positive for anxiety report greater benefit from BCST.

Patient-reported experiences with refractory or unexplained chronic cough: a qualitative analysis

BACKGROUND

Chronic cough, defined as a cough lasting 8 or more weeks, affects up to 10% of adults. Refractory chronic cough (RCC) is a cough that is uncontrolled despite comprehensive investigation and treatment of comorbid conditions while unexplained chronic cough (UCC) is a cough with no identifiable cause despite extensive evaluation of comorbid conditions. RCC and UCC are often poorly controlled. Understanding individuals' lived experience of the symptoms and impacts of these conditions may guide therapeutic strategies.

OBJECTIVES

The primary objectives of this study were to assess respondents' perceptions of the key symptoms of RCC and UCC and the impacts of RCC and UCC and their symptoms on well-being, health-related quality of life, work productivity, and social relationships.

DESIGN

Qualitative study.

METHODS

This study enrolled 30 adults with physician-diagnosed RCC or UCC. Two trained qualitative researchers conducted individual, in-depth telephone interviews using a semi-structured interview guide. Interviews were audio-recorded, transcribed, coded, and systematically analyzed to identify content themes.

RESULTS

A total of 15 respondents with RCC and 15 with UCC were included in the study. Many respondents had RCC or UCC for a long duration (median 9 years, range: 0-24). Half of the respondents reported having a coughing episode at least once daily. Only 40% of respondents reported that medication had improved their symptoms. In over half of the respondents, RCC or UCC hindered communication, caused embarrassment, frustration, and worry, and lowered quality of life. Perceptions of meaningful treatment benefits in RCC or UCC varied widely across respondents.

CONCLUSION

RCC and UCC remained poorly managed in many individuals and were associated with a wide range of symptoms and cough triggers that hindered daily activities and reduced emotional well-being. Understanding individuals' lived experiences may inform the development of RCC and UCC therapeutic strategies.

Palliative Care Early in the Care Continuum among Patients with Serious Respiratory Illness: An Official ATS/AAHPM/HPNA/SWHPN Policy Statement

Background: Patients with serious respiratory illness and their caregivers suffer considerable burdens, and palliative care is a fundamental right for anyone who needs it. However, the overwhelming majority of patients do not receive timely palliative care before the end of life, despite robust evidence for improved outcomes. Goals: This policy statement by the American Thoracic Society (ATS) and partnering societies advocates for improved integration of high-quality palliative care early in the care continuum for patients with serious respiratory illness and their caregivers and provides clinicians and policymakers with a framework to accomplish this. Methods: An international and interprofessional expert committee, including patients and caregivers, achieved consensus across a diverse working group representing pulmonary-critical care, palliative care, bioethics, health law and policy, geriatrics, nursing, physiotherapy, social work, pharmacy, patient advocacy, psychology, and sociology. Results: The committee developed fundamental values, principles, and policy recommendations for integrating palliative care in serious respiratory illness care across seven domains: 1) delivery models, 2) comprehensive symptom assessment and management, 3) advance care planning and goals of care discussions, 4) caregiver support, 5) health disparities, 6) mass casualty events and emergency preparedness, and 7) research priorities. The recommendations encourage timely integration of palliative care, promote innovative primary and secondary or specialist palliative care delivery models, and advocate for research and policy initiatives to improve the availability and quality of palliative care for patients and their caregivers. Conclusions: This multisociety policy statement establishes a framework for early palliative care in serious respiratory illness and provides guidance for pulmonary-critical care clinicians and policymakers for its proactive integration.

Effectiveness of the Therapy Program for Management of Chronic Cough: Preliminary Data From a Randomized Clinical Trial

PURPOSE

The purpose of this study is to analyze the effectiveness of the Therapy Program for Management of Chronic Cough (TMCC) in laryngeal sensations and symptoms related to the cough in individuals with chronic refractory cough (CRC).

METHOD

This research is a randomized double-blind clinical trial (Register Number: RBR-4m6x29). Eleven participants were allocated to two groups by parallel randomization: The Experimental Group-consisting of six individuals who underwent the TMCC; and the Control Group-consisting of five individuals who underwent the Comprehensive Vocal Rehabilitation Program (CVRP). Two primary outcomes were analyzed: self-perception of laryngeal sensations (Newcastle Laryngeal Hypersensitivity Questionnaire [LHQ-Br]) and self-perception of symptoms of upper airway-related cough (Cough Severity Index [CSI-Br]). The two-way repeated-measures analysis of variance was used to compare the evaluation moments and intervention groups. For multiple comparisons, the Tukey test with Bonferroni correction was used. To evaluate the effect size, eta partial square was used.

RESULTS

There was no difference between groups for any outcomes analyzed. There was a statistically significant difference with a large effect size for the moment factor in all outcomes. A statistically significant difference was observed with a large effect size for the interaction effect between group and moment for LHQ-Br total and CSI-Br psychological and functional.

CONCLUSIONS

The TMCC and CVRP were effective for the rehabilitation of CRC, considering the viewpoint of the subject. The TMCC improved laryngeal sensations and psychological and functional symptoms, while CVRP was relevant to improve psychological and functional symptoms in individuals with CRC.

Patient-Reported Qualitative Analysis of Chronic Refractory Cough

PURPOSE

Chronic cough has been shown to be associated with adverse effects on quality of life. There is a paucity of research characterizing quality-of-life factors associated with chronic refractory cough (CRC), a cough persisting > 8 weeks despite evaluation and treatment of possible etiologies. The purpose of this study was to elucidate the features of CRC from the patient's perspective, including presenting symptoms, past treatment methods, and quality-of-life factors.

METHOD

Prospective semistructured interviews were conducted, recorded, and transcribed for 20 patients diagnosed with CRC. Exclusion criteria included lung disease, smoking history, laryngeal cancer, and neurological disease. Grounded theory analysis was completed on transcribed interviews.

RESULTS

Eighteen participants were women. Mean participant age was 53.5 years (SD = 1.41), and average cough duration was 52 months (SD = 71.6 months). Responses to 30 open-ended questions revealed four dominant themes with 24 subthemes.

CONCLUSIONS

CRC affects patient quality of life. Understanding patient perspective on CRC diagnosis and treatment helps providers better understand the physical and emotional toll CRC takes on patients. Findings suggest that providers should spend more time counseling patients regarding their treatment and diagnosis, as patients with CRC do not always fully understand their diagnosis and resort to self-blame.

Cough hypersensitivity and chronic cough

Chronic cough is globally prevalent across all age groups. This disorder is challenging to treat because many pulmonary and extrapulmonary conditions can present with chronic cough, and cough can also be present without any identifiable underlying cause or be refractory to therapies that improve associated conditions. Most patients with chronic cough have cough hypersensitivity, which is characterized by increased neural responsivity to a range of stimuli that affect the airways and lungs, and other tissues innervated by common nerve supplies. Cough hypersensitivity presents as excessive coughing often in response to relatively innocuous stimuli, causing significant psychophysical morbidity and affecting patients' quality of life. Understanding of the mechanisms that contribute to cough hypersensitivity and excessive coughing in different patient populations and across the lifespan is advancing and has contributed to the development of new therapies for chronic cough in adults. Owing to differences in the pathology, the organs involved and individual patient factors, treatment of chronic cough is progressing towards a personalized approach, and, in the future, novel ways to endotype patients with cough may prove valuable in management.

Chronic cough in adults: recommendations from an Italian intersociety consensus

BACKGROUND

Chronic cough (CC) is a burdensome health problem in adult and older people, with a major impact on quality of life. Its management is often troublesome, and many guidelines have been released. Notwithstanding, a proportion of cases still do not reach a definite diagnosis and resolutive treatment. A coordinated approach between different specialists would be highly recommended, but its implementation in clinical practice suffers from the lack of shared protocols and poor awareness of the problem. The present consensus document has been implemented to address these issues.

AIMS

To develop evidence-based recommendations for the management of adults with CC.

METHODS

A 12-member expert task force of general practitioners, geriatricians, pneumologists, allergologists, otorhynolaringologists and gastroenterologists was established to develop evidence-based recommendations for the diagnostic and therapeutic approach to subjects with CC. A modified Delphi approach was used to achieve consensus, and the US Preventive Services Task Force system was used to rate the strength of recommendations and the quality of evidence.

RESULTS

A total of 56 recommendations were proposed, covering 28 topics and concerning definitions and epidemiology, pathogenesis and etiology, diagnostic and therapeutic approach along with the consideration of specific care settings.

CONCLUSION

These recommendations should ease the management of subjects with CC by coordinating the expertise of different specialists. By providing a convenient list of topics of interest, they might assist in identifying unmet needs and research priorities.

Non-pharmacological Management of Non-productive Chronic Cough in Adults: A Systematic Review

Background

Chronic cough is a common reason for medical referral and its prevalence is on the rise. With only one pharmaceutical therapy currently under review for the treatment of refractory chronic cough, exploring non-pharmacological chronic cough management therapies is important. This systematic review summarizes the effectiveness of non-pharmacological chronic cough therapies in adults with non-productive refractory chronic cough or cough due to chronic respiratory diseases.

Methods

We searched Medline, Embase, Cochrane, CINAHL, and Scopus from inception to September 2021. Randomized controlled trials published in English, Portuguese, or French, and examining the effects of non-pharmacological therapies in adults with chronic non-productive cough (>8 weeks; <2 teaspoons sputum) were included. Mean differences, medians, and odds ratios were calculated as appropriate.

Results

16,546 articles were identified and six articles representing five unique studies were included. Studies evaluated 228 individuals with refractory chronic cough or chronic cough due to a chronic respiratory disease [162 women (71%); 52 ± 11 to 61 ± 8 years old]. Obstructive sleep apnea was the only chronic respiratory disease studied. Non-pharmacological therapies included education, cough suppression, breathing techniques, mindfulness, and continuous positive airway pressure. When standing alone, non-pharmacological cough therapies improved cough-specific health related quality of life when not associated with interventions (mean diff MD 1.53 to 4.54), cough frequency (MD 0.59 95%CI 0.36 to 0.95), and voice outcomes (MD 0.3 to 1) when compared to control interventions.

Conclusion

The evidence of non-pharmacological therapies for non-productive chronic cough is limited. Existing studies reflect the heterogeneity in study design, sample size, and outcome measures. Thus, clinical recommendations for using the most effective interventions remain to be confirmed.

WAO-ARIA consensus on chronic cough - Part III: Management strategies in primary and cough-specialty care. Updates in COVID-19

Background

Chronic cough management necessitates a clear integrated care pathway approach. Primary care physicians initially encounter the majority of chronic cough patients, yet their role in proper management can prove challenging due to limited access to advanced diagnostic testing. A multidisciplinary approach involving otolaryngologists and chest physicians, allergists, and gastroenterologists, among others, is central to the optimal diagnosis and treatment of conditions which underly or worsen cough. These include infectious and inflammatory, upper and lower airway pathologies, or gastro-esophageal reflux. Despite the wide armamentarium of ancillary testing conducted in cough multidisciplinary care, such management can improve cough but seldom resolves it completely. This can be due partly to the limited data on the role of tests (eg, spirometry, exhaled nitric oxide), as well as classical pharmacotherapy conducted in multidisciplinary specialties for chronic cough. Other important factors include presence of multiple concomitant cough trigger mechanisms and the central neuronal complexity of chronic cough. Subsequent management conducted by cough specialists aims at control of cough refractory to prior interventions and includes cough-specific behavioral counseling and pharmacotherapy with neuromodulators, among others. Preliminary data on the role of neuromodulators in a proof-of-concept manner are encouraging but lack strong evidence on efficacy and safety.

Objectives

The World Allergy Organization (WAO)/Allergic Rhinitis and its Impact on Asthma (ARIA) Joint Committee on Chronic Cough reviewed the recent literature on management of chronic cough in primary, multidisciplinary, and cough-specialty care. Knowledge gaps in diagnostic testing, classical and neuromodulator pharmacotherapy, in addition to behavioral therapy of chronic cough were also analyzed.

Outcomes

This third part of the WAO/ARIA consensus on chronic cough suggests a management algorithm of chronic cough in an integrated care pathway approach. Insights into the inherent limitations of multidisciplinary cough diagnostic testing, efficacy and safety of currently available antitussive pharmacotherapy, or the recently recognized behavioral therapy, can significantly improve the standards of care in patients with chronic cough.

Effects of transcranial direct current stimulation on cough reflex and urge-to-cough in healthy young adults

Background

Chronic cough is prevalent in the clinic. The existing therapies are mostly limited to medical treatment, with poor curative effects and serious side effects. Studies have suggested that the right dorsolateral prefrontal cortex (rDLPFC) may play an active role in the inhibitory pathway of cough elicitation. Thus, this study explored the effect of transcranial direct current stimulation (tDCS) on the rDLPFC activation in relation to cough reflex and urge-to-cough sensitivity.

Methods

Twenty-three healthy young adults completed the experiment. Participants randomly received tDCS anodal stimulation, cathodal stimulation, and sham stimulation, and the interval between every two stimuli was at least one week. The tDCS (2 mA, 30 min) stimulated brain rDLPFC region. After tDCS intervention, cough reflex threshold and urge-to-cough were evaluated immediately by inhalation of citric acid-saline solution.

Results

Compared with sham stimulation, the cough reflex thresholds logC₂ and logC₅ have increased under tDCS anodal stimulation (1.78 ± 0.55 g/L vs. 1.57 ± 0.57 g/L, p < 0.05; 1.92 ± 0.53 g/L vs. 1.67 ± 0.56 g/L, p < 0.05), accompanied by the increase of the urge-to-cough threshold LogC_u (0.76 ± 0.53 g/L vs. 0.47 ± 0.44 g/L, p < 0.05). In contrast, the urge-to-cough sensitivity expressed as UTC slope was not significantly changed (1.21 ± 0.86 point·L/g vs. 1.00 ± 0.37 point·L/g, p > 0.05), and there were no apparent changes in cough reflex thresholds Log C₂ and logC₅, urge-to-cough threshold LogC_u, and urge-to-cough sensitivity UTC slope under tDCS cathodal stimulation, compared with sham stimulation.

Conclusions

This study found that anodal tDCS stimulation of rDLPFC could significantly decrease cough reflex sensitivity, accompanied by the increase of urge-to-cough threshold. Further investigations targeting different brain regions using multiple central intervention techniques to explore the underlying mechanisms are warranted.

Trial registration The study protocol was registered for the clinical trial in China (registration number: ChiCTR2100045618)

Clinical Practice Guideline: Chronic Cough

BACKGROUND

Chronic cough, i.e., cough lasting longer than eight weeks, affects approximately 10% of the population and is a common reason for outpatient medical consultation. Its differential diagnosis is extensive, and it is generally evaluated in poorly structured fashion with a variety of diagnostic techniques. The German Clinical Practice Guideline on Acute and Chronic Cough was updated in 2021 and contains a description of the recommended stepwise, patient-centered, and evidence-based procedure for the management of chronic cough.

METHODS

The guideline has been updated in accordance with the findings of a systematic search of the literature for international guidelines and systematic reviews. All recommendations were developed in an interdisciplinary manner and agreed upon by formal consensus. The target group consists of adult patients with cough.

RESULTS

History-taking, after the exclusion of red flags, should include questioning about smoking status, medications, and relevant present and past illnesses (COPD, asthma). Subsequent diagnostic testing should include a chest x-ray and pulmonary function tests. If the patient is taking an ACE inhibitor, a test of drug discontinuation can be carried out first. Radiologically detected pulmonary masses or evidence of rare diseases (interstitial lung diseases, bronchiectasis) are an indication for chest CT or for direct referral to an appropriate specialist. If the imaging studies and pulmonary function tests are normal, the patient is most likely suffering from a disease entity that can be treated empirically, such as upper airway cough syndrome or cough variant asthma. Any patient with an unexplained or refractory cough must receive proper patient education; individual therapeutic trials of physiotherapeutic or speechtherapeutic methods are possible, as is the off-label use of gabapentin or morphine.

CONCLUSION

Chronic cough should be evaluated according to an established diagnostic algorithm in collaboration with specialists. Treatments such as inhaled corticosteroids should be tested exhaustively in accordance with the guidelines, and the possibility of multiple causes as well as the role of patient compliance should be kept in mind before a diagnosis of unexplained or intractable cough is assigned.

Curbing the Cough: Multimodal Treatments for Neurogenic Cough: A Systematic Review and Meta-Analysis

OBJECTIVES/HYPOTHESIS

Neurogenic cough affects 11% of Americans and causes significant detriment to quality of life. With the advent of novel therapies, the objective of this review is to determine how procedural therapies (e.g., superior laryngeal nerve block) compare to other established pharmacologic and non-pharmacologic treatments for neurogenic cough.

METHODS

With the assistance of a medical librarian, a systematic review was performed using PICOS (patients, interventions, comparator, outcome, study design) format: adults with neurogenic cough receiving any pharmacologic or non-pharmacologic treatment for neurogenic cough compared to adults with neurogenic cough receiving any other relevant interventions, or treated as single cohorts, assessed with cough-specific quality of life outcomes, in all study designs and case series with ≥ 10 cases. Case reports, review articles, non-human studies, non-English language articles, and unavailable full-text articles were excluded.

RESULTS

There were 2408 patients with neurogenic cough in this review, treated with medical therapy (77%), speech therapy (19%), both medical and speech therapy (1%), and procedural therapy (3%). The included studies ranged from low to intermediate quality. Overall, most interventions demonstrated successful improvement in cough. However, the heterogeneity of included study designs precluded direct comparisons between intervention types.

CONCLUSION

This meta-analysis compared various treatments for neurogenic cough. Procedural therapy should be considered in the armamentarium of neurogenic cough treatments, particularly in patients refractory to, or intolerant of, the side effects of medical therapy. Lastly, this review illuminates key areas for improving neurogenic cough diagnosis, such as strict adherence to diagnostic and treatment guidelines, sophisticated reflux testing, and standardized, consistent outcome reporting. Laryngoscope, 132:107-123, 2022.

Management of intractable chronic cough during awake craniotomy: illustrative case

BACKGROUND

Chronic cough is a common but challenging clinical condition that can adversely affect the safety of awake surgical endeavors such as awake craniotomy (AC). This case lesson highlighted a patient with severe refractory chronic cough undergoing AC for resection of a recurrent left frontal, insula, anterior temporal anaplastic ependymoma of the eloquent cortex.

OBSERVATIONS

The patient was successfully managed using a multifaceted medical treatment regimen combined with preoperative and intraoperative cough suppression therapy with a speech-language pathologist. The patient coughed only once intraoperatively and had a positive outcome.

LESSONS

Chronic cough is often multifactorial and requires a multifaceted treatment approach. Despite this challenge, select patients can successfully be navigated through AC with appropriate treatment for their condition. A review of neurogenic cough and modern treatments, which were used in this patient and would be helpful to neurologists or neurosurgeons, are also discussed.

WAO-ARIA consensus on chronic cough - Part II: Phenotypes and mechanisms of abnormal cough presentation - Updates in COVID-19

BACKGROUND

Chronic cough can be triggered by respiratory and non-respiratory tract illnesses originating mainly from the upper and lower airways, and the GI tract (ie, reflux). Recent findings suggest it can also be a prominent feature in obstructive sleep apnea (OSA), laryngeal hyperresponsiveness, and COVID-19. The classification of chronic cough is constantly updated but lacks clear definition. Epidemiological data on the prevalence of chronic cough are informative but highly variable. The underlying mechanism of chronic cough is a neurogenic inflammation of the cough reflex which becomes hypersensitive, thus the term hypersensitive cough reflex (HCR). A current challenge is to decipher how various infectious and inflammatory airway diseases and esophageal reflux, among others, modulate HCR.

OBJECTIVES

The World Allergy Organization/Allergic Rhinitis and its Impact on Asthma (WAO/ARIA) Joint Committee on Chronic Cough reviewed the current literature on classification, epidemiology, presenting features, and mechanistic pathways of chronic cough in airway- and reflux-related cough phenotypes, OSA, and COVID-19. The interplay of cough reflex sensitivity with other pathogenic mechanisms inherent to airway and reflux-related inflammatory conditions was also analyzed.

OUTCOMES

Currently, it is difficult to clearly ascertain true prevalence rates in epidemiological studies of chronic cough phenotypes. This is likely due to lack of standardized objective measures needed for cough classification and frequent coexistence of multi-organ cough origins. Notwithstanding, we emphasize the important role of HCR as a mechanistic trigger in airway- and reflux-related cough phenotypes. Other concomitant mechanisms can also modulate HCR, including type2/Th1/Th2 inflammation, presence or absence of deep inspiration-bronchoprotective reflex (lower airways), tissue remodeling, and likely cough plasticity, among others.

Long-Term Treatment Outcomes after Behavioral Speech Therapy for Chronic Refractory Cough

INTRODUCTION

Current literature reveals that up to 88% of individuals undergoing behavioral speech therapy (BST) for chronic refractory cough (CRC) demonstrate benefit at 4-8 weeks post-treatment. However, investigations of BST are confounded by overlapping use of neuromodulators, missing follow-up data, and an absence of long-term outcomes. This study investigated treatment outcomes beyond 6 months in individuals diagnosed with CRC, and whose treatment outcomes were clinically undocumented.

METHODS

Participants with CRC 6 months or greater beyond treatment completion were recruited. Participants completed a post-treatment Leicester Cough Questionnaire (LCQ) and a telephone interview. Demographic data, cough characteristics, treatment adherence, BST outcomes, and pre- and post-treatment LCQ scores were evaluated.

RESULTS

80 individuals met inclusion criteria and 29 consented to participate. Of these, 27 were recommended BST. The majority were female (19/27) with average age of 58 years (SD = 12). Mean cough duration was 60 months (SD = 98) and mean post-BST duration was 20 months (SD = 9). A significant increase in pre- to post-treatment LCQ scores occurred [4.4 (SD = 4.2)] (p < 0.0001).

CONCLUSION

This study addressed long-term BST benefit for CRC and demonstrated a significant improvement in long-term post-treatment LCQ total scores more than a year after BST for CRC. More than half of participants indicated improvement or elimination of their cough. These findings further support the benefit of BST for CRC. Future research should consider patient perspectives about treatment outcomes given that 44% of participants reported no benefit from BST.

Presentation of the Therapy Program for Management of Chronic Cough

PURPOSE

To present a proposal for speech-language pathology rehabilitation called the Therapy Program for Management of Chronic Cough (TMCC) for the treatment of refractory chronic cough.

METHODS

TMCC was developed based on two stages: literature and clinical analysis. The literature analysis stage was carried out through the following procedures: electronic and manual search for articles and books published until June 2019 that included adult participants with chronic cough and intervention with speech-language pathology therapy; selection of sources; analysis of articles and books included; and, preparation of the initial version of the therapy program. The initial version of the therapy program resulting from literature analysis stage was submitted to clinical analysis stage through the following procedures: analysis by three judges; revision of the proposal by the authors; judges' re-analysis; elaboration of the final version called the Therapy Program for Management of Chronic Cough (TMCC).

RESULTS

TMCC synthesizes scientific knowledge and current clinical experience on the behavioral management of refractory chronic cough into a program with three main components, each one with specific objectives and strategies. TMCC consists of four sessions, with weekly frequency and duration between 30-45 minutes per session, executed in hierarchical phases, with specific objectives and strategies per session.

CONCLUSION

TMCC is a program structured to offer global cough rehabilitation. To obtain scientific evidence about its effectiveness is necessary, so that it can be used in clinical practice.

Evaluation and Management Outcomes and Burdens in Patients with Refractory Chronic Cough Referred for Behavioral Cough Suppression Therapy

PURPOSE

The purpose of this study was to investigate the typical symptoms and medical management characteristics of adult patients with refractory chronic cough (RCC) who are referred to speech-language pathology (SLP) for behavioral cough suppression therapy (BCST) in order to estimate cost-effectiveness and efficiency of current practice patterns for this population.

METHODS

One hundred sixty-four (164) patients with RCC referred for BCST were surveyed. Patients completed an initial survey at BCST onset related to symptom pattern and prior treatment, including the Leicester Cough Questionnaire (LCQ). Every four to six weeks patients completed follow-up surveys to assess their response to BCST.

RESULTS

Mean age was 58 years (83.5% women). The majority of patients reported their cough began two or more years prior to BCST. Approximately half (49%) reported seeing four or more physicians (including primary care physicians) and being prescribed four or more medications (57%) prior to BCST. Medications targeting post-nasal drip (72%), reflux (70%), asthma (56%), and allergies (56%) were most commonly prescribed. BCST resulted in a clinically significant improvement in 70.1% of participants. The mean change in LCQ for those who improved with BCST was 6.61. Over half (58%) reported they were quite satisfied to completely satisfied with their treatment response. The average time from enrollment to study completion was 64 days.

CONCLUSION

The results of this study suggest early intervention with BCST may be a cost-effective and efficient option for patients with RCC.

Management of chronic refractory cough in adults

Cough is a common respiratory symptom that is considered to be chronic when it lasts more than eight weeks. When severe, chronic cough may significantly impact an individual's quality of life, and such patients are frequently referred for specialist evaluation. Current international guidelines provide algorithms for the management of chronic cough: in most cases, treatment of the underlying disease is sufficient to improve or resolve cough symptoms. Severe chronic cough may significantly affect patients' quality of life and necessitate frequent referral for specialist evaluations. In this narrative review, we summarize non-pharmacologic and pharmacologic management of adult patients with chronic cough of known cause that persists after proper treatment (chronic refractory cough, CRC) or chronic cough of unknown cause in adult patients. If chronic cough persists even after treatment of the underlying disease, or if the chronic cough is not attributable to any cause, then a symptomatic approach with neuromodulators may be considered, with gabapentin as the first choice, and opioids or macrolides as alternatives. Speech pathology treatment and/or neuromodulators should be discussed with patients and alternative options carefully considered, taking into account risk/benefit. Novel promising drugs are under investigation (e.g. P2×3 inhibitors), but additional studies are needed in this field. Speech pathology can be combined with a neuromodulator to give an enhanced treatment response of longer duration suggesting that non-pharmacologic treatment may play a key role in the management of CRC.

Peripheral and central mechanisms of cough hypersensitivity

Chronic cough is a difficult to treat symptom of many respiratory and some non-respiratory diseases, indicating that varied pathologies can underpin the development of chronic cough. However, clinically and experimentally it has been useful to collate these different pathological processes into the single unifying concept of cough hypersensitivity. Cough hypersensitivity syndrome is reflected by troublesome cough often precipitated by levels of stimuli that ordinarily don't cause cough in healthy people, and this appears to be a hallmark feature in many patients with chronic cough. Accordingly, a strong argument has emerged that changes in the excitability and/or normal regulation of the peripheral and central neural circuits responsible for cough are instrumental in establishing cough hypersensitivity and for causing excessive cough in disease. In this review, we explore the current peripheral and central neural mechanisms that are believed to be involved in altered cough sensitivity and present possible links to the mechanism of action of novel therapies that are currently undergoing clinical trials for chronic cough.

Cough Severity Index in Brazilian Portuguese: Translation and Cross-Cultural Adaptation

OBJECTIVE

To translate and cross-culturally adapt the Cough Severity Index to Brazilian Portuguese.

MATERIAL AND METHODS

This is a study with observational, cross-sectional, and analytical design. The procedure for translation and cross-cultural adaptation followed the recommendations of the Scientific Advisory Committee of the Medical Outcomes Trust and was performed in five stages: translation, synthesis, back translation, committee review, and pretesting. The sample for the pretest consisted of 34 participants with refractory chronic cough, 11 males and 23 females, with an average age of 48 years and 1 month.

RESULTS

The title of the questionnaire, the answer options, and seven of the ten questions were agreed upon by three judges, the remaining three questions were retranslated by a fourth judge. After back-translation and committee review, editing of question five was necessary. The option "never" was more frequently selected for four questions and the option "always" for six questions. There was a significantly higher proportion of other response categories of the instrument compared to the response category "not applicable."

CONCLUSION

This study resulted in the elaboration of a translated and cross-culturally adapted version of the Cough Severity Index in Brazilian Portuguese.

Upper Airway Pathology Contributes to Respiratory Symptoms in Children Born Very Preterm

OBJECTIVE

To evaluate the role of upper airway dysfunction, indicated by altered vocal quality (dysphonia), on the respiratory symptoms of children surviving very preterm birth.

STUDY DESIGN

Children born <32 weeks of gestation participated in 2 separate assessments during midchildhood. The first visit assessed voice quality by a subjective evaluation using the Consensus Auditory-Perceptual Evaluation of Voice and a computerized analysis of the properties of the voice via the Acoustic Voice Quality Index. The second assessment recorded parentally reported respiratory symptoms and measures of lung function, including spirometry, lung volumes, oscillatory mechanics, and a cardiopulmonary exercise test.

RESULTS

Preterm children (n = 35; median gestation 24.3 weeks) underwent paired voice and lung assessments at approximately 11 years of age. Preterm children with dysphonia (n = 25) reported significantly more respiratory symptoms than those with normal voices (n = 10) including wheeze (92% vs 40%; P = .001) and asthma diagnosed by a physician (60% vs 10%; P = .007). Lung function outcomes were generally not different between the dysphonic group and the group with normal voice (P > .05), except for the oscillatory mechanics measures, which were all at least 0.5 z score lower in the dysphonic group (Xrs₈ mean difference = -0.91 z scores, P = .003; f_res = 1.06 z scores, P = .019; AX = -0.87 z scores, P = .010; Rrs₈ = 0.63 z scores, P = .068).

CONCLUSIONS

The upper airway may play a role in the respiratory symptoms experienced by some very preterm children and should be considered by clinicians, especially when symptoms are in the presence of normal lung function and are refractory to treatment.

The management of chronic cough

Chronic cough is a common presentation to primary care and constitutes a significant volume of referrals to secondary care. It affects around 10% of the adult population and has a plethora of respiratory and non-respiratory causes. It can have a significant impact on the quality of life of affected individuals. In many patients, minimal baseline investigations lead to an easily identifiable and treatable cause. In others, no cause can be identified even after extensive investigations in specialized cough clinics. This evidence-based review article outlines the approach to the adult patient presenting with chronic cough and focuses upon current management strategies in those with chronic idiopathic cough. It includes results from trials of speech and language therapies, and the emerging concept of chronic idiopathic cough as a neuropathic disorder with its own bespoke approach to management including the use of neuromodulatory agents.

An Update on Speech Pathology Management of Chronic Refractory Cough

Chronic cough is a common, debilitating condition that can persist for years with little relief from medical treatment. Speech pathology treatment is an effective treatment option for patients with chronic cough. This review outlines current speech pathology assessment and treatment for chronic cough and describes the evidence supporting the intervention. The rationale for speech pathology intervention is described with reference to speech pathology training and expertise that are relevant for this condition. Despite the efficacy and advantages of speech pathology intervention, there is limited guidance in the literature on when patients should be referred for treatment. Patients suitable for speech pathology intervention are those whose cough has persisted despite medical management. Speech pathology intervention may be particularly beneficial for patients with coexisting laryngeal disorders such as muscle tension dysphonia or inducible laryngeal obstruction. Limited information is available regarding current speech pathology training, practice, and service delivery for chronic cough internationally. Timely referral for speech pathology intervention could reduce the disease burden for individuals with chronic cough and decrease the economic burden of this complex condition.

A new approach to the classification and management of airways diseases: identification of treatable traits

This review outlines a new, personalized approach for the classification and management of airway diseases. The current approach to airways disease is, we believe, no longer fit for purpose. It is impractical, overgeneralizes complex and heterogeneous conditions and results in management that is imprecise and outcomes that are worse than they could be. Importantly, the assumptions we make when applying a diagnostic label have impeded new drug discovery and will continue to do so unless we change our approach. This review suggests a new mechanism-based approach where the emphasis is on identification of key causal mechanisms and targeted intervention with treatment based on possession of the relevant mechanism rather than an arbitrary label. We highlight several treatable traits and suggest how they can be identified and managed in different healthcare settings.

Change in Psychological, Physiological, and Situational Factors in Adults After Treatment of Chronic Cough

BACKGROUND

We hypothesized that addressing anxiety and depressive mood disorders will improve chronic cough severity and cough quality of life (CQOL).

METHODS

Major tenets of the theory of unpleasant symptoms were examined in a longitudinal observational study of consecutive adults with cough of > 8 weeks' duration treated in our cough clinic. At baseline and 3 and 6 months, subjects completed 3 Punum Ladders rating cough severity, the CQOL Questionnaire, the Depression, Anxiety, and Stress Scales-21, and the Duke Functional Social Support Questionnaire. Cross-sectional baseline and longitudinal regression analyses were conducted.

RESULTS

Eighty subjects (55 women) with a mean age of 58.5 ± 11.1 years and a cough duration of 86.0 ± 123.7 months were enrolled. At baseline, worse cough severity was significantly associated with less education and worse ability to speak bothered by cough and the urge to cough. Worse CQOL was significantly associated with worse depression symptoms, urinary incontinence, and ability to speak; use of self-prescribed remedies; and younger age. Significant improvements in depression and stress symptoms occurred at 3 and 6 months. Anxiety symptoms improved, particularly in the first 3 months. Improvement in cough severity was significantly associated with less education, male sex, and improvement in ability to speak and urge to cough. Improvement in CQOL was significantly associated with improvement in urinary incontinence, urge to cough, anxiety symptoms, and use of self-prescribed remedies.

CONCLUSIONS

Using the theory of unpleasant symptoms, we have come to appreciate that managing psychological, physiological, and situational factors in addition to focusing on identifying the cause of cough is important to maximize improvement in CQOL.

The Emerging Role of The Eosinophil and Its Measurement in Chronic Cough

Although the aetiology of chronic cough in guidelines is clearly stated as asthma and related syndromes, gastro-oesophageal reflux disease (GORD), and upper airways disease, the inflammatory mechanisms underlying these conditions differ. Recent studies on asthma have increasingly focused on its molecular phenotypes instead of clinical characteristics. Here, we proposed the hypothesis that divides cough into two groups; the eosinophilic and neutrophilic. This division will enhance our ability to recognise the type of airway inflammation which, as a consequence will lead us to more targeted and personalized treatment approaches.

Physiotherapy and Speech and Language therapy intervention for chronic cough

There are few effective pharmacological therapies available to treat refractory chronic cough. Functional MRI studies of the brain have recently shown that patients with chronic cough have dysfunctional inhibitory control of cough. Self-management therapies delivered by physiotherapists or speech therapists are effective at suppressing cough. They enable patients to consciously suppress the urge to cough. The intervention consists of education, laryngeal hygiene, cough suppression and distraction measures and behaviour modification. The efficacy of Physiotherapy and Speech And Language Intervention (PSALTI) has been confirmed in two randomised control trials. In one trial, there was a 41% reduction in cough frequency with PSALTI, assessed objectively with the Leicester Cough Monitor, and a clinically significant improvement in quality of life. Importantly, the improvement in cough was sustained when therapy was discontinued. The addition of the Speech Pathology Treatment to neuromodulator drug therapy, Pregabalin has also been evaluated in a clinical trial. There was a clinically significant improvement in quality of life, and this was sustained when therapy was discontinued. The mechanism of action of PSALTI is not known and this should be investigated in future. Further studies are needed to identify the components of PSALTI that deliver the most benefit, and determine whether PSALTI is effective in cough associated with other chronic lung disorders.

Symptomatic Treatment of Cough Among Adult Patients With Lung Cancer: CHEST Guideline and Expert Panel Report

BACKGROUND

Cough among patients with lung cancer is a common but often undertreated symptom. We used a 2015 Cochrane systematic review, among other sources of evidence, to update the recommendations and suggestions of the American College of Chest Physicians (CHEST) 2006 guideline on this topic.

METHODS

The CHEST methodologic guidelines and the Grading of Recommendations, Assessment, Development, and Evaluation framework were used. The Expert Cough Panel based their recommendations on data from the Cochrane systematic review on the topic, uncontrolled studies, case studies, and the clinical context. Final grading was reached by consensus according to the Delphi method.

RESULTS

The Cochrane systematic review identified 17 trials of primarily low-quality evidence. Such evidence was related to both nonpharmacologic (cough suppression) and pharmacologic (demulcents, opioids, peripherally acting antitussives, or local anesthetics) treatments, as well as endobronchial brachytherapy.

CONCLUSIONS

Compared with the 2006 CHEST Cough Guideline, the current recommendations and suggestions are more specific and follow a step-up approach to the management of cough among patients with lung cancer, acknowledging the low-quality evidence in the field and the urgent need to develop more effective, evidence-based interventions through high-quality research.

Physiotherapy, and speech and language therapy intervention for patients with refractory chronic cough: a multicentre randomised control trial

BACKGROUND

Physiotherapy, and speech and language therapy are emerging non-pharmacological treatments for refractory chronic cough. We aimed to investigate the efficacy of a physiotherapy, and speech and language therapy intervention (PSALTI) to improve health-related quality of life (HRQoL) and to reduce cough frequency in patients with refractory chronic cough.

METHODS

In this multicentre randomised controlled trial, patients with refractory chronic cough were randomised to four weekly 1:1 sessions of either PSALTI consisting of education, laryngeal hygiene and hydration, cough suppression techniques, breathing exercises and psychoeducational counselling or control intervention consisting of healthy lifestyle advice. We assessed the change in HRQoL at week 4 with the Leicester Cough Questionnaire (LCQ). Secondary efficacy outcomes included 24-hour objective cough frequency (Leicester Cough Monitor) and cough reflex sensitivity. The primary analysis used an analysis of covariance adjusted for baseline measurements with the intention-to-treat population. This study was registered at UK Clinical Research Network (UKCRN ID 10678).

FINDINGS

Between December 2011 and April 2014, we randomly assigned 75 participants who underwent baseline assessment (34 PSALTI and 41 controls). In the observed case analysis, HRQoL (LCQ) improved on average by 1.53 (95% CI 0.21 to 2.85) points more in PSALTI group than with control (p=0.024). Cough frequency decreased by 41% (95% CI 36% to 95%) in PSALTI group relative to control (p=0.030). The improvements within the PSALTI group were sustained up to 3 months. There was no significant difference between groups in the concentration of capsaicin causing five or more coughs.

INTERPRETATION

Greater improvements in HRQoL and cough frequency were observed with PSALTI intervention. Our findings support the use of PSALTI for patients with refractory chronic cough.

TRIAL REGISTRATION NUMBER

UKCRN ID 10678 and ISRCTN 73039760; Results.

Treatment of Chronic Cough: Single-Institution Experience Utilizing Behavioral Therapy

Objective

Chronic cough remains a challenging condition, especially in cases where it persists despite comprehensive medical management. For these particular patients, there appears to be an emerging role for behavior modification therapy. We report a series of patients with refractory chronic cough to assess if there is any benefit of adding behavioral therapy to their treatment regimen.

Study Design

A case series with planned chart review of patients treated for chronic cough.

Setting

The review was performed with an outpatient electronic health record system at a tertiary care center.

Subjects and Methods

The charts of all patients treated for chronic cough by a single laryngologist over a 30-month period were analyzed. Patients’ response to treatment and rate of cough improvement were assessed for those with refractory chronic cough who underwent behavior modification therapy.

Results

Thirty-eight patients with chronic cough were initially treated empirically for the most common causes of cough, of which 32% experienced improvement. Nineteen patients who did not significantly improve with medical management underwent behavior modification therapy with a speech-language pathologist. Of these patients, 84% experienced resolution or marked improvement of their symptoms.

Conclusion

Behavioral therapy may be underutilized in practice and could lead to improvement of otherwise recalcitrant cough.

Cough modulation by upper airway stimuli in cat - potential clinical application?

The modulation of mechanically induced tracheobronchial cough was tested by applying various stimuli and the elicitation of other airway protective behaviors in pentobarbital anesthetized cats. Capsaicin and histamine were injected in the nose, and mechanical nylon fiber and / or air puff stimulation was applied to the nose and nasopharynx. Reflex responses of cough, sneeze, aspiration reflex and expiration reflex were induced mechanically. Swallow was initiated by the injection of water into oropharynx. Subthreshold mechanical stimulation of nasopharyngeal and nasal mucosa, as well as water stimulation in the oropharynx and larynx, with no motor response, had no effect on rhythmic coughing. Cough responsiveness and excitability increased with capsaicin and air puff stimuli delivered to the nose. Vice versa, the number of cough responses was reduced and cough latency increased when aspiration reflexes (>1) occurred before the cough stimulus or within inter-cough intervals (passive E2 cough phase). The occurrence of swallows increased the cough latency as well. Cough inspiratory and / or expiratory motor drive was enhanced by the occurrence of expiration reflexes, swallows, and sneezes and also by aspiration reflex within the inspiratory phase of cough and by nasal air puff stimuli. Complex central interactions, ordering and sequencing of motor acts from the airways may result in the disruption of cough rhythmic sequence but also in the enhancement of cough. Our data confirm that number of peripheral stimuli and respiratory motor responses significantly alters cough performance. We propose developing and testing stimulation paradigms that modify coughing and could be employed in correcting of inappropriate or excessive coughing.

Airway Hypersensitivity, Reflux, and Phonation Contribute to Chronic Cough

BACKGROUND & AIMS

Although chronic cough is common, its etiology is often elusive, making patient management a challenge. Gastroesophageal reflux and airway hypersensitivity can cause chronic cough. We explored the relationship between reflux, phonation, and cough in patients with idiopathic chronic cough.

METHODS

We performed a blinded, cross-sectional study of nonsmoking patients with chronic cough (duration, >8 weeks) refractory to reflux treatment referred to the Digestive Disease Center at Vanderbilt University. All underwent 24-hour acoustic recording concurrently and temporally synchronized with ambulatory pH-impedance monitoring. Cough, phonation, and pH-impedance events were recorded. We evaluated the temporal relationship between cough and phonation or reflux events using Poisson and logistic regression.

RESULTS

Seventeen patients met the inclusion criteria (88% female; 100% white; median age, 63 years [interquartile age range, 52-66 years]; mean body mass index, 30.6 [interquartile range, 27.9-34.0]); there were 2048 analyzable coughing events. The probability of subsequent coughing increased with higher burdens of preceding cough, reflux, or phonation. Within the first 15 minutes after a cough event, the cough event itself was the main trigger of subsequent cough events. After this period, de novo coughing occurred with increases of 1.46-fold in association with reflux alone (95% confidence interval, 1.17-1.82; P < .001) and 1.71-fold in association with the combination of phonation and reflux events.

CONCLUSIONS

Antecedent phonation and reflux increased the rate of cough events in patients with idiopathic chronic cough. Reflux events were more strongly associated with increased rate of coughing. Our findings support the concept that airway hypersensitivity is a cause of chronic cough, and that the vocal folds may be an effector in chronic cough ClinicalTrials.gov number: NCT01263626.

Treatment of Unexplained Chronic Cough: CHEST Guideline and Expert Panel Report

BACKGROUND

Unexplained chronic cough (UCC) causes significant impairments in quality of life. Effective assessment and treatment approaches are needed for UCC.

METHODS

This systematic review of randomized controlled trials (RCTs) asked: What is the efficacy of treatment compared with usual care for cough severity, cough frequency, and cough-related quality of life in patients with UCC? Studies of adults and adolescents aged > 12 years with a chronic cough of > 8 weeks' duration that was unexplained after systematic investigation and treatment were included and assessed for relevance and quality. Based on the systematic review, guideline suggestions were developed and voted on by using the American College of Chest Physicians organization methodology.

RESULTS

Eleven RCTs and five systematic reviews were included. The 11 RCTs reported data on 570 participants with chronic cough who received a variety of interventions. Study quality was high in 10 RCTs. The studies used an assortment of descriptors and assessments to identify UCC. Although gabapentin and morphine exhibited positive effects on cough-related quality of life, only gabapentin was supported as a treatment recommendation. Studies of inhaled corticosteroids (ICS) were affected by intervention fidelity bias; when this factor was addressed, ICS were found to be ineffective for UCC. Esomeprazole was ineffective for UCC without features of gastroesophageal acid reflux. Studies addressing nonacid gastroesophageal reflux disease were not identified. A multimodality speech pathology intervention improved cough severity.

CONCLUSIONS

The evidence supporting the diagnosis and management of UCC is limited. UCC requires further study to establish agreed terminology and the optimal methods of investigation using established criteria for intervention fidelity. Speech pathology-based cough suppression is suggested as a treatment option for UCC. This guideline presents suggestions for diagnosis and treatment based on the best available evidence and identifies gaps in our knowledge as well as areas for future research.

The relationship between cough-specific quality of life and abdominal muscle endurance, fatigue, and depression in patients with COPD

BACKGROUND

Cough is a prevalent symptom that impacts quality of life in COPD. The aim of this study was to assess the relationship between cough-specific quality of life, abdominal muscle endurance, fatigue, and depression in stable patients with COPD.

METHODS

Twenty-eight patients with COPD (mean age 60.6±8.7 years) referred for pulmonary rehabilitation participated in this cross-sectional study. Sit-ups test was used for assessing abdominal muscle endurance. Leicester Cough Questionnaire (LCQ) was used to evaluate symptom-specific quality of life. Fatigue perception was evaluated with Fatigue Impact Scale (FIS). Beck Depression Inventory (BDI) was used for assessing depression level.

RESULTS

The LCQ total score was significantly associated with number of sit-ups; BDI score; FIS total; physical, cognitive, and psychosocial scores (P<0.05). Scores of the LCQ physical, social, and psychological domains were also significantly related with number of sit-ups, FIS total score, and BDI score (P<0.05). FIS total score and number of sit-ups explained 58% of the variance in LCQ total score (r=0.76, r (2)=0.577, F(2-20)=12.296, P<0.001).

CONCLUSION

Chronic cough may adversely affect performance in daily life due to its negative effect on fatigue and decrease abdominal muscle endurance in patients with COPD. Decreased cough-related quality of life is related with increased level of depression in COPD patients. Effects of increased abdominal muscle endurance and decreased fatigue in COPD patients with chronic cough need further investigation.

Cough hypersensitivity as a neuro-immune interaction

Cough is an intrinsic protective reflex. However, chronic cough affects a considerable proportion of general population and has a major impact on quality of life. A recent paradigm shift to ‘cough hypersensitivity syndrome’ suggests that chronic cough arises from hypersensitivity of the airway sensory nerves. As cough reflex is determined by interaction of the nervous system with immune system, persistent dysregulation of one or both of these systems may lead to chronic cough hypersensitivity. Here we review the current evidence for the neuro-immune interactions that underlie cough hypersensitivity and discuss future therapeutic strategies.

Management of the respiratory distress symptom cluster in lung cancer: a randomised controlled feasibility trial

Background

Breathlessness, cough and fatigue are distressing symptoms for patients with lung cancer. There is evidence that these three symptoms form a discreet symptom cluster. This study aimed to feasibly test a new non-pharmacological intervention for the management of the Respiratory Distress Symptom Cluster (breathlessness-cough-fatigue) in lung cancer.

Method

This was a multi-centre, randomised controlled non-blinded parallel group feasibility trial. Eligible patients (patients with primary lung cancer and ‘bothered’ by at least two of the three cluster symptoms) received usual care plus a multicomponent intervention delivered over two intervention training sessions and a follow-up telephone call or usual care only. Follow-up was for 12 weeks, and end-points included six numerical rating scales for breathlessness severity, Dyspnoea-12, Manchester Cough in Lung Cancer scale, FACIT-Fatigue scale, Hospital Anxiety and Depression scale, Lung Cancer Symptom Scale and the EQ-5D-3L, collected at baseline, week 4 and week 12.

Results

One hundred seven patients were randomised over 8 months; however, six were removed from further analysis due to protocol violations (intervention group n = 50 and control group n = 51). Of the ineligible patients (n = 608), 29 % reported either not experiencing two or more symptoms or not being ‘bothered’ by at least two symptoms. There was 29 % drop-out by week 4, and by week 12, a further two patients in the control group were lost to follow-up. A sample size calculation indicated that 122 patients per arm would be needed to detect a clinically important difference in the main outcome for breathlessness, cough and fatigue.

Conclusions

The study has provided evidence of the feasibility and acceptability of a new intervention in the lung cancer population and warrants a fully powered trial before we reach any conclusions. The follow-on trial will test the hypothesis that the intervention improves symptom cluster of breathlessness, cough and fatigue better than usual care alone. Full economic evaluation will be conducted in the main trial.

Clinical perspective - cough: an unmet need

Cough is among the most common complaints for which individuals worldwide seek medical attention. The vast majority of cases of acute cough (<3 weeks duration) are due to acute viral upper respiratory tract infection (URI) (common cold). Fortunately, acute cough is typically transient and self-limited. However, should severe and/or persistent acute cough require pharmacological treatment, satisfactory therapeutic options are scarce. Narcotic antitussives are limited by unacceptable side effects at therapeutic doses, and most over-the-counter (OTC) remedies are not supported by adequate clinical trials. The goal in chronic cough (>8 weeks duration) is to meticulously evaluate and treat all potential underlying etiologies. Despite thorough investigation, a significant minority of patients will suffer refractory, unexplained cough. For this challenging population, safe, effective, non-narcotic antitussive therapies are desperately needed.

Recent additions in the treatment of cough

BACKGROUND

Worldwide, cough is regarded as a challenging clinical problem due to its frequency and often limited therapeutic options. Chronic cough that remains refractory to usual medical treatment causes significant quality of life impairment in people with this problem.

METHODS

We have examined current evidence on recent additions in the treatment of cough, specifically treatment of refractory chronic cough with speech pathology and gabapentin. Relevant randomised control trials, reviews and case reports were identified through a PubMed and SCOPUS search of English-language literature referring to these concepts over the last eight years.

SUMMARY

Of the one hundred and two articles comprising this review the majority investigated the role of the transient receptor potential (TRP) receptors TRP Vanilloid 1 (TRPV1) and TRPA1 in cough and the potential of TRP antagonists as effective anti-tussives. However, these have only been tested in the laboratory and therefore their clinical effectiveness is unknown. Behavioural treatments such as speech pathology have gained momentum and this was evident in the increasing number of articles investigating its positive effect on cough. Investigation on the effectiveness of neuromodulating medications in the treatment of cough have been supported primarily through case series reports and prospective reviews however; their use (particularly gabapentin) has been significantly advanced through recently conducted randomised controlled trials.

CONCLUSIONS

Recent additions in the treatment of chronic cough have been significant as they consider cough to have a unifying diagnosis of cough hypersensitivity with or without the presence of a neuropathic basis. Primarily, effective treatments for chronic cough target these areas and include behavioural treatment such as speech pathology and pharmaceutical treatment with neuromodulating medications such as gabapentin.