Efficacy of gefapixant, a P2X3 antagonist, for lung cancer-related cough: a case report

Cough is a frequent symptom accompanied by lung cancer. More potent antitussive treatment for this complex and distressing symptom is required, but anti-cancer chemotherapy cannot fully manage the cough. Inhibition of vagal nerves might control coughing in patients with troublesome lung cancer-related cough and P2X3 inhibitory therapy may be useful for targeting neuronal function. We report the case of a woman in her late 70s who never smoked and had advanced lung cancer. She visited our hospital complaining of serious deterioration of a non-productive cough. She was diagnosed with relapse of lung cancer, but she requested 2-week anti-tussive therapy before second-line chemotherapy. Gefapixant (P2X3 antagonist) add-on at a dose of 90 mg/day (45 mg twice daily as the usual dosage in Japan) improved her cough as indicated by an improvement in the visual analog scale for cough from 70 to 20 mm and in the Japanese version of the Leicester Cough Questionnaire from 8.2 to 16.3, despite a deterioration in lung cancer after 2 weeks. There are no current guidelines for cough accompanied by lung cancer; however, our findings suggest that P2X3 inhibition is a potent therapeutic option for lung cancer-related cough.

Cough desensitization treatment for patients with refractory chronic cough: results of a second pilot randomized control trial

OBJECTIVE

The purpose of this study was to collect pilot efficacy data on a novel treatment for refractory chronic cough (RCC), which we call cough desensitization treatment (CDT).

DESIGN AND METHODS

In this parallel cohort, sham-controlled, randomized controlled trial, 21 adults with RCC were randomly assigned to 12 sessions of either CDT (progressive doses of aerosolized capsaicin while behaviorally suppressing cough; n = 11) or a sham treatment (repeated exposure to aerosolized saline; n = 9). The Leicester Cough Questionnaire (LCQ) was the primary outcome measure. Perceived cough severity with a visual analogue scale and cough challenge testing (for measuring cough-reflex sensitivity) were secondary outcome measures. Data were analyzed with mixed effects linear regression and follow-up contrasts.

RESULTS

Results on all measures favored CDT. Excluding one sham participant, whose baseline LCQ scores were deemed unreliable, mean change in LCQ at 3-weeks post treatment was 6.35 and 2.17 in the CDT and sham groups, respectively. There was moderate to strong evidence of a greater improvement in the CDT group in total LCQ score (p = .058) and LCQ Psychological domain (p = .026) and Physical domain (p = .045) scores. Strong evidence was found for a greater reduction in urge-to-cough during CCT in the CDT group (p = .037) and marginal for a reduction in the capsaicin cough-reflex sensitivity (p = .094). There was weak evidence of a greater reduction in cough severity in the CDT group (p = .103).

DISCUSSION

Although the study is limited due to the small sample size, the data provide additional evidence supporting further research on CDT. CDT resulted in a greater change in the primary efficacy measure (LCQ) than both pharmaceutical and behavioral treatments currently found in the literature.

TRIAL REGISTRATION

This trial (NCT05226299) was registered on Clinicaltrials.gov on 07/02/2022.

Comparison of postoperative cough-related quality of life and recovery between sublobectomy and lobectomy for early-stage non-small cell lung cancer patients: a longitudinal study

Background

Cough is a common complication after pulmonary surgery. Previous studies lacked a standard measure to assess postoperative cough-related quality of life and recovery. The purpose of this study is to compare postoperative cough regarding changes in health-related quality of life (HRQOL) and recovery trajectory between video-assisted thoracic surgery (VATS) lobectomy and sublobectomy (segmentectomy or wedge resection) for early-stage non-small cell lung cancer (NSCLC) patients via the Leicester Cough Questionnaire in Mandarin Chinese (LCQ-MC).

Methods

Overall, 156 patients with NSCLC underwent either VATS lobectomy or VATS sublobectomy; LCQ-MC was used to report the impact of postoperative cough on HRQOL for 6 months after surgery. The total scores of LCQ-MC range from 3 to 21, with a higher score indicating better health. Recovery from postoperative cough was defined as LCQ-MC scores returning to preoperative levels. The sensitivity of LCQ-MC to changes in postoperative cough recovery over time was evaluated via its ability to distinguish between surgery types.

Results

The VATS sublobectomy group reported significantly higher mean LCQ-MC scores at 1 month after surgery, but no significant difference postoperatively at 3 and 6 months after surgery, and returned to preoperative physical (69 vs. 99 days), psychological (67 vs. 99 days), social (50 vs. 98 days) and total (69 vs. 99 days) scores faster than the VATS lobectomy group (all p < 0.05).

Conclusion

VATS sublobectomy had generally better HRQOL and faster recovery of postoperative cough than VATS lobectomy. In addition, the LCQ-MC performed satisfactorily in describing the longitudinal changes in postoperative cough.

Leicester Cough Questionnaire validation and clinically important thresholds for change in refractory or unexplained chronic cough

INTRODUCTION

The Leicester Cough Questionnaire (LCQ), a cough-specific quality-of-life measure, evaluates the impact of cough across physical, psychological, and social domains in patients with chronic cough (CC). This study assessed the psychometric properties of the LCQ.

METHODS

Data from a phase IIb, randomized controlled trial of the P2X3-receptor antagonist gefapixant were analyzed (NCT02612610). Subjective [Cough Severity Diary, cough severity visual analogue scale, and patient global impression of change (PGIC)] and objective (awake and 24-h cough frequency) data were used to validate the LCQ for use in patients with refractory or unexplained CC (RCC and UCC, respectively). Psychometric analyses included confirmatory factor analyses, internal consistency and test-retest reliability, validity, responsiveness, and estimated within-patient thresholds for clinically meaningful change.

RESULTS

Model-fit values for the proposed three-factor LCQ domains and most individual items were acceptable. Analyses suggest that a mean improvement ranging from 1.3 to 2.3 points for the LCQ total and ⩾0.8, ⩾0.9, and ⩾0.8 points for physical, psychological, and social domain scores, respectively, had the best sensitivity and/or specificity for predicting patient ratings of improvement on the PGIC.

CONCLUSIONS

The LCQ is a valid and reliable measure to evaluate cough-specific quality of life and is a fit-for-purpose measure for use in patients with RCC or UCC. Although a single threshold for defining clinically meaningful change depends on the context of use, the results can help guide both treatment decisions and drug development. Therefore, clinicians may consider a ⩾1.3-point increase in the LCQ total score as clinically meaningful.

Validation of a visual analog scale for assessing cough severity in patients with chronic cough

Introduction:

Patients with chronic cough experience considerable burden. The cough severity visual analog scale (VAS) records patients’ assessment of cough severity on a 100-mm linear scale ranging from “no cough” (0 mm) to “worst cough” (100 mm). Although cough severity scales are widely used in clinical practice and research, their use in patients with refractory or unexplained chronic cough has not been formally validated.

Methods:

This analysis includes data from a phase 2b randomized controlled trial of the P2X3-receptor antagonist gefapixant for treatment of refractory or unexplained chronic cough (NCT02612610). Cough severity VAS scores were assessed at baseline and Weeks 4, 8, and 12. The cough severity VAS was validated using several outcomes, including the Cough Severity Diary (CSD), Leicester Cough Questionnaire (LCQ), patient global impression of change (PGIC) scale, and objective cough frequency. Validation metrics included test–retest reliability, convergent and known-groups validity, responsiveness, and score interpretation (i.e., clinically meaningful change threshold).

Results:

The analysis included 253 patients (median age, 61.0 years; females, 76%). Test–retest reliability of the cough severity VAS was moderate (intraclass correlation coefficient, 0.51). The cough severity VAS had acceptable convergent validity with other related measures (Pearson r of 0.53 and -0.41 for CSD and LCQ total scores, respectively; p < 0.0001 for each). Known-groups validity was supported by significant differences in mean cough severity VAS scores across severity groups defined using CSD, LCQ, and cough frequency tertiles. A large effect size was observed in patients with the greatest improvements in PGIC (Cohen d = -1.8). A ⩾ 30-mm reduction in the cough severity VAS was estimated as a clinically meaningful change threshold for clinical trials in chronic cough.

Conclusions:

The cough severity VAS is a valid and responsive measure. A cough severity VAS reduction of ⩾ 30 mm can discriminate clinically meaningful changes in chronic cough severity in clinical studies.

Is the Leicester Cough Questionnaire useful for nontuberculous mycobacterial lung disease?

BACKGROUND

Although the incidence of nontuberculous mycobacterial lung disease (NTM-LD) is increasing worldwide, there is no established standard of care leading to eradication. Therefore, research on health-related quality of life (HRQOL) is important for patients with NTM-LD. HRQOL is commonly evaluated using the St. George's Respiratory Questionnaire (SGRQ), developed for chronic obstructive pulmonary disease (COPD). However, NTM-LD differs from COPD in that few patients complain of dyspnea or wheezing, and cough and sputum are their main symptoms. The Leicester Cough Questionnaire (LCQ) is an HRQOL questionnaire dedicated to cough, but few studies have used it for NTM-LD. This study evaluated HRQOL in patients with NTM-LD using the SGRQ and LCQ and clarified the usefulness of the LCQ.

METHODS

Information on age, height, weight, lung function, percent ideal body weight, laboratory data, radiological scores, exercise capacity, SGRQ, and LCQ were collected from the medical records of 81 patients. Correlations between SGRQ and LCQ domains were assessed using Spearman's rank correlation coefficients. Multivariate analysis was performed with SGRQ and LCQ total scores.

RESULTS

Statistically significant correlations were observed between all domains, and the correlation between the total scores was -0.67 (p < 0.01). Multivariate analysis with total scores as the dependent variable showed that the explanatory variables were lung function (p < 0.05) and radiological score (p < 0.05) in the SGRQ, and radiological score (p < 0.05) and C-reactive protein level (p < 0.05) in the LCQ.

CONCLUSION

The LCQ, which evaluates an inflammatory response involved in the diagnosis of NTM-LD, may be useful to assess HRQOL in patients with NTM-LD.

Benign Vocal Fold Lesions in Patients with Chronic Cough

OBJECTIVE

The objective of this study was to determine the prevalence of benign vocal fold lesions (BVFLs) in patients with chronic cough over a 1-year period.

STUDY DESIGN

Case series with chart review.

SETTING

Tertiary academic medical center.

SUBJECTS AND METHODS

A retrospective cohort study of patients with chronic cough seen in our tertiary multidisciplinary cough clinic from 2016 to 2017 was conducted. Patient characteristics, presence of BVFLs by laryngoscopy, and Leicester Cough Questionnaire (LCQ) were recorded.

RESULTS

A total of 419 patients were included (average age: 61 years), and 67% of patients were female. Ten percent of patients had BVFLs: granuloma (5%), leukoplakia (3%), nodules (2%), and polyps (1%). Median cough duration was 2.9 years (interquartile range [IQR], 0.7-8.5); no significant difference in median cough duration was observed between patients with BVFLs and those with no lesions (2.6 vs 3.0 years, P = .86). In total, 178 patients (42%) had available LCQ data: median score of 10.2 (IQR, 7.9-13.9); no significant difference in median LCQ was observed between patients with BVFLs and those with no lesions (10.5 vs 10.1, P = .54).

CONCLUSION

Prevalence of BVFLs in our cohort of patients with chronic cough was 10%, with posterior glottic lesions-granuloma-being the most common (5%). Prevalence of midmembranous lesions was as follows: vocal fold nodules (2%) and vocal fold polyps (1%). BVFLs were not associated with longer cough duration or more severe cough. We cannot determine a causative or noncausative relationship between BVFLs and chronic cough at this time due to lack of a control group.

Quantitative measurement properties and score interpretation of the Cough Severity Diary in patients with chronic cough

AIMS

The Cough Severity Diary (CSD) was developed in accordance with the FDA guidance for patient-reported outcome measures and is focused on capturing the patient's perception of cough in terms of frequency, intensity, and disruption due to their cough. The measure includes a series of seven items asking patients to rate the frequency (three items), intensity (two items), and disruptiveness (two items) of their cough. The instrument was designed to be completed daily before bedtime, has a recall period of 'today,' and responses to items are entered on an 11-point numeric rating scale ranging from 0 to 10 with anchors on each end. The objective of this analysis was to confirm the domain structure of the CSD and assess its reliability, validity, and responsiveness in adult patients with refractory or unexplained chronic cough (RCC/UCC). Criteria for defining meaningful changes in mean weekly CSD total and domain scores in the context of a clinical trial were also developed.

METHODS

Pooled data from a phase II randomized controlled trial of an investigational treatment for RCC/UCC were analyzed. Participants were non-smokers, had RCC/UCC for ⩾1 year, and a baseline cough severity visual analogue scale (VAS) ⩾40 mm. CSD scores (baseline, week 4), were analyzed; the Leicester Cough Questionnaire (LCQ), cough severity VAS, Patient Global Impression of Change (PGIC), and objective cough frequency counts were used for validation. CSD domain structure (Total, Frequency, Intensity, Disruption) was assessed for scoring.

RESULTS

A total of 253 participants were included (mean age 60.2; 76% female). Global fit of the three-factor CSD was acceptable. For the CSD total score, internal consistency (α = 0.89) and test-retest reliability (intraclass correlation coefficient = 0.68) were high. CSD total scores were correlated with the LCQ total (r = -0.62) and cough severity VAS (r = 0.84). Participants with a PGIC score of 1 or 2 (most improved groups) had the greatest mean score improvement on the CSD Total (Day 0 to Day 28), supporting responsiveness (similar findings for subscales). A change threshold of ⩾1.3-point reduction on the total and subscale scores is appropriate to define clinically meaningful improvement.

CONCLUSION

The CSD is a reliable, valid, and responsive measure of cough symptom severity in patients with refractory or unexplained chronic cough and fit-for-purpose for assessing changes in cough severity in clinical trials. The reviews of this paper are available via the supplemental material section.

Improved cough- and sputum-related quality of life after initiation of treatment in pulmonary tuberculosis

BACKGROUND

Cough and sputum are the major symptoms of pulmonary tuberculosis (TB). However, the relationship between these symptoms and treatment for TB is not fully understood. The aim of this prospective study was to clarify the cough- and sputum-related quality of life (QOL) in patients with pulmonary TB before and after initiation of treatment.

METHODS

The study included 85 patients with active pulmonary TB who were hospitalized from July 2014 to August 2015. They completed the Leicester Cough Questionnaire (LCQ: range 3-21, the higher the better) and the Cough and Sputum Assessment Questionnaire (CASA-Q: range 0-100, the higher the better) on admission and at discharge after 2 months of treatment.

RESULTS

The LCQ and CASA-Q scores were reduced on admission. A multivariate linear regression analysis revealed that younger age, more than two cavitary lesions, and the presence of bronchial TB were associated with reduced LCQ total score. However, each score significantly improved at discharge, regardless of the initial grade of the sputum smear, site of the lesion, number of cavitary lesions, and presence of bronchial TB. The change in the mean LCQ total score was 2.28 (95% confidence interval, 1.56-3.00). The changes in the mean CASA-Q cough symptoms, cough impact, sputum symptoms, and sputum impact scores were 22.84 (18.44-27.25), 10.96 (7.20-14.71), 17.25 (13.33-21.18), and 5.25 (2.49-8.00), respectively.

CONCLUSIONS

Cough- and sputum-related QOL was impaired in patients with pulmonary TB before treatment but improved after initiation of treatment regardless of the clinical characteristics.

Vitamin D3 supplementation in adults with bronchiectasis: A pilot study

Vitamin D supplementation prevents acute respiratory infections and, through modulating innate and adaptive immunity, could have a potential role in bronchiectasis management. The primary aims of this pilot study were to assess serum 25-hydroxyvitamin D (25(OH)D) levels in New Zealand adults with bronchiectasis, and their 25(OH)D levels after vitamin D3 supplementation. Adults with bronchiectasis received an initial 2.5 mg vitamin D3 oral loading dose and 0.625 mg vitamin D3 weekly for 24 weeks. The primary outcome was serum 25(OH)D levels before and after vitamin D3 supplementation. Secondary outcomes (time to first infective exacerbation, exacerbation frequency, spirometry, health-related quality of life measures, sputum bacteriology and cell counts and chronic rhinosinusitis) were also assessed. This study is registered with the Australian New Zealand Clinical Trials Registry (ACTRN 12612001222831). The initial, average 25(OH)D level was 71 nmol/L (95% confidence interval (CI): [58, 84]), rising to 218 nmol/L (95% CI: [199, 237]) at 12 weeks and 205 nmol/L (95% CI: [186, 224]) at 24 weeks. The initial serum cathelicidin level was 25 nmol/L (95% CI: [17, 33]), rising to 102 nmol/L (95% CI: [48, 156]) at 12 weeks and 151 nmol/L (95% CI: [97, 205]) at 24 weeks. Over the 24-week study period, we observed statistically significant changes of 1.11 (95% CI: [0.08, 2.14]) in the Leicester Cough Questionnaire and -1.97 (95% CI: [-3.71, -0.23]) in the Dartmouth COOP charts score. No significant adverse effects were recorded. Many New Zealand adults with bronchiectasis have adequate 25(OH)D levels. Weekly vitamin D3 supplementation significantly improved 25(OH)D levels.

The validity and reliability of the Turkish version of the Leicester Cough Questionnaire in COPD patients

Background/aim

The reliability and validity of the Turkish version of the Leicester Cough Questionnaire (LCQ) have been evaluated before. This study aimed to validate the Turkish version of the LCQ in chronic obstructive pulmonary disease (COPD) patients with cough.

Materials and methods

COPD (GOLD B, C, D) patients over age 40 (n = 75) and healthy volunteers as a control group (n = 75) were included. A sociodemographic data form, the LCQ, the Short Form-36 (SF-36) quality of life questionnaire, and the World Health Organization Quality of Life Brief Form for Turkish people were completed. The internal reliability of the LCQ was determined using the Cronbach alpha coefficient (>0.6) and its repeatability by the intraclass consistency coefficient (P < 0.05) was accepted as significant.

Results

For internal consistency, Cronbach alpha coefficients of all subscales of the LCQ, physical, psychological, and social, were found as 0.72, 0.86, and 0.83, respectively, with 0.92 for the total index. There was significant internal consistency for all subscales and the total index (Cronbach alpha coefficients of >0.6). In test–retest reliability, the correlation coefficient ranged between 0.71 and 0.80 for each question and was calculated as r = 0.89 for total LCQ score (P < 0.001).

Conclusion

The Turkish version of the LCQ has been found to have acceptable reliability and validity for use in Turkish COPD patients with chronic cough.

Assessing referral and practice patterns of patients with chronic cough referred for behavioral cough suppression therapy

The purpose of this exploratory research was to describe current referral and practice patterns for behavioral cough suppression therapy (BCST) throughout the United States, and to assess the need for improving the efficiency of BCST referral patterns. In study I, 126 speech-language pathologists, who treat patients with refractory chronic cough (RCC) in the United States, completed a survey about referral patterns, cough duration, and patient frustration level. In study II, 36 adults with RCC referred for BCST completed a four-part survey about cough symptoms and treatment. The survey included the Leicester Cough Questionnaire (LCQ) before and after BCST. Study I revealed significant patient frustration about the treatment process and the wait-time for BCST. Participants in study II reported average cough duration of over 2 years before BCST. Twenty-seven of 31 participants in study II improved by at least 1.3 on the LCQ, indicating a clinically significant improvement in 87% of patients. This study suggests that the current management model for CC may be unduly time-consuming, and expensive for patients with CC who are successfully treated with BCST. Practitioners are encouraged to consider BCST earlier in the treatment process.

Minimal Clinically Important Differences (MCIDs) of the Thai Version of the Leicester Cough Questionnaire for Subacute and Chronic Cough

OBJECTIVES

To investigate the minimal clinically important differences (MCIDs) of the Thai version of the Leicester Cough Questionnaire (LCQ-T) in patients with subacute and chronic cough.

METHODS

Patients with cough for 3 or more weeks were recruited from outpatient clinics. They self-completed the LCQ-T at an initial evaluation and repeated the LCQ-T with a Global Rating of Change scale at follow-up. For the anchor-based method, the MCID was defined as a change in the LCQ scores that corresponded to the smallest improvement in Global Rating of Change score (+2 to +3). For distribution-based methods, the MCIDs were estimated from the standard error of measurement and a half and one-third of the SD of the LCQ score changes from baseline to follow-up.

RESULTS

A total of 107 patients were included. The causes of cough were postinfectious cough/bronchitis (35.5%), asthma (20.6%), rhinosinusitis (16.8%), bronchiectasis (17.8%), and chronic obstructive pulmonary disease (9.3%). The anchor-based method yielded MCIDs of 1.1, 0.4, 0.4, and 0.4 for the total, physical, psychological, and social domains, respectively. The distribution-based method using standard error qof measurement yielded MCIDs of 0.8, 0.3, 0.3, and 0.3, whereas those using a half SD yielded MCIDs of 2.0, 0.6, 0.8, and 0.8 and those using one-third SD yielded MCIDs of 1.4, 0.4, 0.5, and 0.5 for the total, physical, psychological, and social domains, respectively.

CONCLUSIONS

The MCIDs of the LCQ-T for subacute and chronic cough are 1.1, 0.4, 0.4, and 0.4 for the total, physical, psychological, and social domains, respectively. These estimates should be useful in making meaningful interpretations of the changes in quality of life because of cough.

Chronic Non-Productive Cough in Patients With Primary Sjögren's Syndrome

Objectives

This study aims to evaluate the frequency of chronic cough due to dryness in the trachea and the relationship between depression and chronic cough in patients with primary Sjögren's syndrome (pSS).

Patients and methods

Eighty non-smoking patients (7 males, 73 females; mean age 47.6±9.2 years; range 18 to 70 years) with newly diagnosed pSS were included. All patients were evaluated clinically, radiologically, and physiologically. Patients with cough were assessed using the Leicester Cough Questionnaire and visual analog scale. Beck Depression Inventory was used to determine the risk of depression in patients with cough. Patients with asthma, rhinosinusitis, gastrooesophageal reflux, and drug use which cause cough and pulmonary involvement in pSS were excluded.

Results

Non-productive cough was detected in 30 patients (37.5%). Fourteen patients (17.5%) were admitted to the hospital with cough at least once before the diagnosis of pSS. The median time between onset of symptoms and firm diagnosis was 24 months (25-75 interquartile ranges: 3-60 months). A significant difference was observed in the Beck Depression Inventory scores between patients with and without cough. There was a significant negative relationship between Leicester Cough Questionnaire and Beck Depression Inventory scores.

Conclusion

Patients with pSS often have symptoms for a long duration that mimic those of more commonly encountered non-specific pulmonary conditions. Xerotrachea should be considered in the differential diagnosis of chronic cough, especially in patients with normal pulmonary function tests and pulmonary imaging.

Airway inflammation, cough and athlete quality of life in elite female cross-country skiers: A longitudinal study

The aim of this study was to investigate the effect of a season of cross-country training and racing on airway inflammation, cough symptoms, and athlete quality of life in female skiers. Eighteen elite female skiers performed sputum induction and completed the Leicester Cough Questionnaire (LCQ) and the Recovery-Stress Questionnaire (REST-Q) at three time points (T1 - May/Jun, T2 - Oct/Nov, T3 - Jan-Mar) during the year. No changes were observed between T1 and T2. However, an increase in sputum eosinophils and lymphocytes (P < 0.05) and a significant change in all three domains of the LCQ were observed between T1 and T3 (P < 0.05). A significant association was found between the total yearly hours of training and the change in the total cell count (r(2)  = 0.74; P = 0.006), and a number of other sputum cell counts between T1 and T3. No changes were observed for any domain of the REST-Q. The results of this study demonstrate that airway inflammation and cough symptoms are significantly increased in elite female cross-country skiers across a year of training and racing. The increase in airway inflammation is related to the total amount of training and is worse during the winter months when athletes are training and racing in cold, dry air.

Adjunctive treatment with oral AKL1, a botanical nutraceutical, in chronic obstructive pulmonary disease

Purpose

The objective of this pilot trial was to evaluate the safety and efficacy of AKL1, a patented botanical formulation containing extracts of Picrorhiza kurroa, Ginkgo biloba, and Zingiber officinale, as add-on therapy for patients with chronic obstructive pulmonary disease (COPD) and chronic cough.

Patients and methods

This randomized, double-blind, placebo-controlled trial enrolled male and female patients >18 years old with COPD and Leicester Cough Questionnaire (LCQ) score of <18. The 10-week study period comprised a 2-week single-blind placebo run-in period followed by add-on treatment with AKL1 or placebo twice daily for 8 weeks. The primary study endpoint was the change from week 0 to week 8 in cough-related health status, as assessed by the LCQ.

Results

Of 33 patients enrolled, 20 were randomized to AKL1 and 13 to placebo. Patients included 19 (58%) men and 14 (42%) women of mean (standard deviation [SD]) age of 67 (9.4) years; 15 (45%) patients were smokers and 16 (49%) were ex-smokers. The mean (SD) change from baseline in LCQ score at 8 weeks was 2.3 (4.9) in the AKL1 group and 0.6 (3.7) in the placebo group, with mean difference in change of 1.8 (95% confidence interval: −1.5 to 5.1; P=0.28). The St George’s Respiratory Questionnaire score improved substantially in the AKL1 treatment group by a mean (SD) of −7.7 (11.7) versus worsening in the placebo group (+1.5 [9.3]), with mean difference in change of −9.2 (95% confidence interval: −19.0 to 0.6; P=0.064). There were no significant differences between treatment groups in change from baseline to week 8 in other patient-reported measures, lung function, or the 6-minute walk distance.

Conclusion

Further study is needed with a larger patient population and over a longer duration to better assess the effects of add-on therapy with AKL1 in COPD.

Reliability and validity of Leicester Cough Questionnaire Korean version

The Leicester Cough Questionnaire (LCQ) is a self-administered questionnaire developed in England and validated for reliability. We developed a Korean translation of this questionnaire by applying a sequential forward and backward translation approach. The purpose of this study is to validate the Korean version of the LCQ (LCQ-K) in Korean patients with chronic cough. A multicenter prospective study was undertaken with 100 chronic cough patients who consented to participate in the study. The LCQ-K includes eight physical items, seven psychological items, and four social items. Visual analog scale (VAS) of cough, Borg Cough Scale (BCS), and Short Form-36 (SF-36) were used as external comparators. Participants included 52 women and 48 men with ages ranging from 18 years to 69 years. The concurrent validity comparing LCQ-K to VAS, BCS, and SF-36 yielded statistically significant Pearson correlation coefficients. The LCQ-K showed good reliability in three domains, with Cronbach's α coefficients ranging from 0.84 to 0.87 (total: 0.91). Test-retest reliability was investigated with single measure intraclass correlation coefficients, which were found to be practically and statistically significant (p = 0.005). Responsiveness was validated by effective size ranging from 1.16 to 1.40 in each domain. LCQ-K is a reliable, valid, and responsive disease-specific questionnaire for assessing symptoms and quality of life of Korean patients with chronic cough.