Feasibility and clinical utility of ambulatory cough monitoring in an outpatient clinical setting: a real-world retrospective evaluation.

RESEARCH QUESTION: Objective quantification of cough is rarely utilised outside of research settings and the role of cough frequency monitoring in clinical practice has not been established. This study examined the clinical utility of cough frequency monitoring in an outpatient clinical setting. METHODS: The study involved a retrospective review of cough monitor data. Participants included 174 patients referred for treatment of cough and upper airway symptoms (103 chronic cough; 50 inducible laryngeal obstruction; 21 severe asthma) and 15 controls. Measures, taken prior to treatment, included 24-h ambulatory cough frequency using the Leicester Cough Monitor, the Leicester Cough Questionnaire and Laryngeal Hypersensitivity Questionnaire. Post-treatment data were available for 50 participants. Feasibility and clinical utility were also reported. RESULTS: Analysis time per recording was up to 10 min. 75% of participants could use the monitors correctly, and most (93%) recordings were interpretable. The geometric mean cough frequency in patients was 10.1±2.9 (mean±sd) compared to 2.4±2.0 for healthy controls (p=0.003). There was no significant difference in cough frequency between clinical groups (p=0.080). Cough frequency decreased significantly following treatment (p<0.001). There was a moderate correlation between cough frequency and both cough quality of life and laryngeal hypersensitivity. Cough frequency monitoring was responsive to therapy and able to discriminate differences in cough frequency between diseases. CONCLUSION: While ambulatory cough frequency monitoring remains a research tool, it provides useful clinical data that can assist in patient management. Logistical issues may preclude use in some clinical settings, and additional time needs to be allocated to the process.

Laryngeal Dysfunction in Severe Asthma: A Cross-Sectional Observational Study.

BACKGROUND: Laryngeal disorders can contribute to disease burden in severe asthma yet the nature of laryngeal disorders in severe asthma is poorly understood. OBJECTIVE: The aim of this study was to examine laryngeal function in patients with severe asthma. METHOD: A cross-sectional observational study involving 97 participants compared laryngeal function in patients with severe asthma (n = 53) with patients with laryngeal disorders of vocal cord dysfunction/inducible laryngeal obstruction (n = 16) and muscle tension dysphonia (n = 14), and with healthy controls (n = 13). A pre-post pilot study of speech pathology intervention for laryngeal symptoms was then provided to 11 participants with severe asthma and laryngeal dysfunction. RESULTS: Laryngeal dysfunction was common in severe asthma. The majority of participants with severe asthma (87%) had laryngeal dysfunction, which affected respiration, phonation, or both. Three distinct patterns of laryngeal dysfunction in severe asthma were identified: (1) phonatory laryngeal dysfunction, (2) respiratory laryngeal dysfunction, and (3) combined laryngeal dysfunction. Laryngeal hypersensitivity and impaired voice measures were common in severe asthma. Patient-reported outcome measures improved after therapy, and laryngeal dysfunction improved in 7 (64%) participants. CONCLUSION: Laryngeal dysfunction affects respiration and phonation in severe asthma. It requires identification and treatment to minimize its impact on asthma symptoms.

Chronic cough in Vocal Cord Dysfunction: Description of a clinical entity.

BACKGROUND AND AIM: Vocal Cord Dysfunction (VCD) and chronic cough (CC) are challenging conditions which lead to significant quality of life impairment. The underlying mechanisms are poorly understood, but laryngeal dysfunction may be common to both conditions. The aim of this study was to determine the characteristics of cough in VCD and whether patients with cough have coexisting VCD. METHOD: Participants included 51 patients with VCD and a comparison group of 39 patients with chronic cough that was refractory to medical treatment. Participants underwent a comprehensive assessment including questionnaires, laryngoscopy, cough frequency monitoring and voice testing. RESULTS: Patients with VCD had significant cough morbidity with an increased cough frequency of 17.3 coughs/hour and reduced cough quality of life with mean Leicester Cough Questionnaire Score of 12.8. Breathing pattern abnormalities were also common in VCD and there was a strong correlation between the number of breathing pattern abnormalities and cough frequency (r = -0.827, p = 0.002). Cough measures were not significantly different between patients with VCD and those with CC. Moderate-severe PVFM was present in 69% of patients with CC. Abnormal vocal fold closure during phonation was also present in patients with chronic cough and was similar between the VCD (n = 40, 78.4%) and cough (n = 25, 64.1%) groups, p = 0.240. CONCLUSION: Cough is an important symptom in VCD. Patients presenting with chronic cough may have underlying VCD as a cause of their cough. Since cough and VCD symptoms co-occur clinicians need to consider cough when are treating VCD and VCD when treating chronic cough.

Speech Pathology Intervention for Chronic Refractory Cough: A Pilot Study Examining the Benefit of Using Prerecorded Videos as an Adjunct to Therapy.

Speech pathology intervention is effective for chronic refractory cough (CRC). Speech pathology treatment for CRC includes therapy exercises to teach cough suppression and reduce laryngeal closure during respiration. AIM: The aim of this study was to evaluate the benefit of providing patients with supplemental pre-recorded videos of speech pathology exercises for chronic refractory cough (CRC) to assist with patients' independent practice. These videos were pre-made recordings of the treating speech pathologist demonstrating specific exercises for chronic cough suppression. METHOD: This study was a prospective randomized controlled trial design. Participants included 18 adult patients attending a speech pathology outpatient clinic in a tertiary referral hospital for treatment of CRC. Participants were randomized to receive either standard speech pathology intervention (SPI) for CRC combined with supplemental pre-recorded videos for home practice or standard SPI alone. The primary outcome measure was a rating of accuracy during demonstration of the speech pathology exercises for cough suppression. This rating was assigned by the treating speech pathologist from session 2 onwards. The treating speech pathologist asked the patient to demonstrate the exercises they had been practising since the last speech pathology session. Secondary outcome measures included the Symptom Frequency and Severity Rating Scale, Leicester Cough Questionnaire, and Consensus Auditory Perceptual Evaluation of Voice. RESULTS: There was a significant pre- to post-treatment improvement in both groups however the degree of improvement was not significantly different between the two groups. CONCLUSION: The addition of supplemental pre-recorded videos of SPI for CRC did not lead to greater accuracy of therapy exercise practice or superior treatment outcomes than standard SPI alone. DECLARATION OF INTEREST: There are no interests to declare.

Pregabalin and Speech Pathology Combination Therapy for Refractory Chronic Cough: A Randomized Controlled Trial.

BACKGROUND: Chronic refractory cough (CRC) is a difficult problem to treat. Speech pathology treatment (SPT) improves symptoms but resolution is incomplete. Centrally acting neuromodulators also improve cough symptoms, but not cough reflex sensitivity, and the effect is short-lived. We hypothesized that combined SPT and centrally acting neuromodulators would have a superior outcome than SPT alone. Our goal was to determine whether combined pregabalin and SPT is more effective than SPT alone. METHODS: Randomized placebo controlled trial. Forty patients with CRC were randomly assigned to receive either combined SPT and pregabalin 300 mg daily or combined SPT and placebo. Outcome measures were collected at baseline, end of treatment, and 4 weeks after the end of treatment. Primary outcome measures were cough frequency using the Leicester Cough Monitor, cough severity using a visual analog scale (coughVAS), and cough-related quality of life (QOL) using the Leicester Cough Questionnaire (LCQ). RESULTS: Cough severity, cough frequency, and cough QOL improved in both groups. The degree of improvement in LCQ and coughVAS was greater with combined SPT and pregabalin than SPT alone; the mean difference in LCQ was 3.5, 95%CI of difference 1.1 to 5.8; the mean difference in coughVAS was 25.1, 95% CI of difference 10.6 to 39.6. There was no significant difference in improvement in cough frequency between groups. There was no deterioration in symptoms once pregabalin was withdrawn. Median capsaicin cough sensitivity improved from 15.7 to 47.5 µM with combined SPT and pregabalin and from 3.92 to 15.7 µM with SPT alone. CONCLUSIONS: Combined SPT and pregabalin reduces symptoms and improves QOL compared with SPT alone in patients with CRC.