Epidemiology and Prognostic Significance of Cough in Fibrotic Interstitial Lung Disease.

Rationale: Cough is a key symptom in patients with fibrotic interstitial lung disease (ILD). Objective: This study evaluated the prevalence, longitudinal change, associations, and prognostic significance of cough severity in patients with fibrotic ILD. Methods: We included consecutive patients with idiopathic pulmonary fibrosis (IPF) and non-IPF fibrotic ILD who completed the 100mm-Cough Severity Visual Analog Scale (VAS) from the prospective multi-center Canadian Registry for Pulmonary Fibrosis. Baseline cough severity and associations with patient demographics and clinical factors were determined. Relationships between baseline cough severity and health outcomes were evaluated. Measurements and Main Results: Patients with IPF (n=1061) had higher median baseline cough severity than those with non-IPF fibrotic ILD (n=2825) [24 vs 20mm, p<0.001], with worse cough associated with gastroesophageal reflux disease for both cohorts. Worse cough severity was independently associated with worse health-related quality of life at baseline, larger annualized decline in DLCO, development of disease progression, and reduced transplant-free survival in both IPF and non-IPF fibrotic ILD cohorts. The IPF cohort (2.2mm, 95% CI 1.6-2.9mm) had larger annualized increments in cough severity compared to the non-IPF fibrotic ILD cohort (1.1mm, 95% CI 0.8-1.4mm; p=0.004). There was no difference in worsening cough over time comparing those receiving and not receiving ILD-targeted therapy or with and without lung function decline. Conclusion: Cough is common in patients with IPF and non-IPF fibrotic ILD, with increasing cough severity over time irrespective of ILD-targeted therapy. Patient-reported cough severity has prognostic implications on health-related quality of life, disease progression, and survival in fibrotic ILD.

An observational study to understand burden and cost of care in adults diagnosed with refractory chronic cough (RCC) or unexplained chronic cough (UCC).

BACKGROUND: Refractory and unexplained chronic cough (RCC and UCC) necessitate frequent referral for specialist evaluations, but data on healthcare resource utilisation and costs are lacking. METHODS: This observational study enrolled adults with RCC or UCC attending a specialist cough clinic and included a control cohort, both from North West England, matched 1:5 for age, gender and smoking history. Primary and secondary care data were obtained for the 5 years prior to and 2 years post initial clinic visit (index). The primary endpoint was the total 5-year healthcare cost to the UK NHS pre-RCC or UCC diagnosis compared to the control cohort. RESULTS: Mean age at index for the 200 RCC or UCC consented patients was 62.2 ± 11.4 years; 71% were female, and 68% had never smoked. Mean duration of symptoms pre-diagnosis was 8.0 ± 9.4 years. Mean cough severity score was 63.7 ± 23.2 mm at index on a Visual Analog Scale, and Leicester Cough Questionnaire total score was 10.9 ± 4.1. GP data were available for 80 patients and mean total cost over the 5 years pre-diagnosis (index date) was 3.0-fold higher (95% CI 2.3, 3.9) than in the control cohort (p < 0.001). Most excess costs were related to visits and procedures carried out in secondary care. RCC- or UCC-associated costs decreased post-diagnosis, but remained higher than those of controls. CONCLUSION: Diagnosis of RCC or UCC requires significant health resource utilisation in the 5 years prior to a specialist clinic diagnosis. Resource utilisation was less after diagnosis, but remained higher than in a matched control cohort.

Positive effect of deep diaphragmatic breathing training on gastroesophageal reflux-induced chronic cough: a clinical randomized controlled study.

BACKGROUND AND OBJECTIVE: To explore the efficacy of deep diaphragmatic breathing training (DEP) in patients with gastroesophageal reflux-induced chronic cough (GERC). METHODS: A randomized controlled study was conducted involving 60 GERC patients who were divided into the intervention group and the control group (each with 30 patients). Both groups received routine medication treatment for GERC, while the intervention group received DEP training additionally. Both groups were evaluated by cough symptom scores, Hull airway reflux questionnaire (HARQ), gastroesophageal reflux diagnostic questionnaire (GerdQ), generalized anxiety disorder scale-7 (GAD-7), patient health questionnaire-9 (PHQ-9), Pittsburgh sleep quality index (PSQI), the Leicester cough questionnaire (LCQ), as well as capsaicin cough sensitivity testing, B-ultrasound and surface electromyography (sEMG) of the diaphragmatic muscles before and after treatment. The cough resolution rate and changes of the above indictors was compared between the two groups after eight weeks of treatment. RESULTS: After eight weeks of treatment, cough symptoms improved in both groups, but the cough resolution rate in the intervention group of 94% was significantly higher than that in the control group of 77% (χ2 = 6.402, P = 0.041). The intervention group showed significant improvements to the control group in GerdQ (6.13(0.35) VS 6.57(0.77)), GAD-7 (0(0;1) VS 1(0;3)), PSQI (2(1;3) VS 4(3;6)), LCQ (17.19(1.56) VS 15.88(1.92)) and PHQ-9 (0(0;0) VS 0(0;3)) after treatment. Compared to control group, sEMG activity of the diaphragmatic muscle was significantly increased in the intervention group after treatment, measured during DEP (79.00(2.49) VS 74.65 (1.93)) and quiet breathing (72.73 (1.96) VS 67.15 (2.48)). CONCLUSION: DEP training can improve cough symptoms as an adjunctive treatment in GERC patients. TRIAL REGISTRATION: The protocol was registered in February 2, 2022 via the Chinese Clinical Trials Register ( http://www.chictr.org.cn/ ) [ChiCTR2200056246].

Pharmacodynamics, pharmacokinetics and CYP3A4 interaction potential of the selective P2X3 receptor antagonist filapixant: A randomized multiple ascending-dose study in healthy young men.

AIMS: We report on investigations exploring the P2X3-receptor antagonist filapixant's effect on taste perception and cough-reflex sensitivity and describe its pharmacokinetics, including its CYP3A4-interaction potential. METHODS: In a randomized, placebo-controlled, double-blind study, 3 × 12 healthy men (18-45 years) were assigned (3:1) to filapixant (20, 80 or 250 mg by mouth) or placebo twice daily over 2 weeks. A single dose of midazolam (1 mg), a CYP3A4 substrate, was administered with and without filapixant. Assessments included a taste-strips test, a taste questionnaire, cough challenge with adenosine triphosphate, adverse event reports and standard safety assessments. RESULTS: Taste disturbances were observed mainly in the 250-mg group: six of nine participants (67%) in this group reported hypo- or dysgeusia in the questionnaire; eight participants (89%) reported taste-related adverse events. Five participants (56%) had a decrease in overall taste-strips-test scores ≥2 points (point estimate -1.1 points, 90% confidence interval [-3.3; 1.1]). Cough counts increased with adenosine triphosphate concentration but without major differences between treatments. Filapixant exposure increased proportionally to dose. Co-administration of filapixant had no clinically relevant effect on midazolam pharmacokinetics. Area under the concentration-time curve ratios and 90% confidence intervals were within 80-125%. No serious or severe adverse events were reported. CONCLUSIONS: Overall, filapixant was safe and well tolerated, apart from mild, transient taste disturbances. Such disturbances occurred more frequently than expected based on (in vitro) receptor-selectivity data, suggesting that other factors than P2X3:P2X2/3 selectivity might also play an important role in this context. The cough-challenge test showed no clear treatment effect. Filapixant has no clinically relevant CYP3A4 interaction potential.

Does diet quality moderate the long-term effects of discrete but extreme PM2.5 exposure on respiratory symptoms? A study of the Hazelwood coalmine fire.

In 2014, a fire at an open cut coalmine in regional Victoria, Australia burned for 6 weeks. Residents of the nearby town of Morwell were exposed to smoke, which included high levels of fine particulate matter (PM2.5). We investigated whether the long-term effects of PM2.5 on respiratory health were moderated by diet quality. A cross-sectional analysis was conducted of data collected 8.5 years after the mine fire from 282 residents of Morwell and 166 residents from the nearby unexposed town of Sale. Primary outcomes were respiratory symptoms. Exposure was coalmine fire-related PM2.5 and diet quality was assessed as Australian Recommended Food Score (ARFS) derived using the Australian Eating Survey (AES). The moderating effect of diet quality on respiratory outcomes associated with PM2.5 was assessed using logistic regression models, adjusting for potential confounders. Diet quality was poor in this sample, with 60% in the lowest category of overall diet quality. Overall diet quality and fruit and vegetable quality significantly attenuated the association between PM2.5 and prevalence of chronic cough and phlegm. Sauce/condiment intake was associated with a greater effect of PM2.5 on COPD prevalence. No other moderating effects were significant. The moderating effects of overall diet quality and vegetable and fruit intake aligned with a priori hypotheses, suggesting potential protective benefits. While more evidence is needed to confirm these findings, improving diets, especially fruit and vegetable intake, may provide some protection against the effects of smoke exposure from fire events.

Yellow Nail Syndrome: Analysis of 23 Consecutive Patients and Effect of Combined Fluconazole-Vitamin-E Treatment.

INTRODUCTION: Yellow nail syndrome (YNS), a very rare disorder of unknown etiology, is characterized by a triad associating yellow nails, respiratory manifestations, and lymphedema. YNS treatment remains non-codified. METHOD: This retrospective study was conducted from January 2008 to December 2022 in a single tertiary department exclusively dedicated to lymphatic diseases. All consecutive patients with YNS were included. RESULTS: Thirteen men and 10 women were included. Three patients had yellow nails at birth or during childhood. For the other 20 patients, median (Q1-Q3) age at first sign was 50.8 (43-61) years, with first-YNS-sign-to-diagnosis interval of 17 (10-56) months. For 4 patients, YNS was associated with primary intestinal lymphangiectasia. The first YNS sign was chronic cough (45.5%), followed by yellow nails (27.3%), chronic sinusitis (18.2%), and lymphedema (9.1%). At first consultation for all patients, 69.6% had the complete triad, all had yellow nails and cough, 82.6% had chronic sinusitis, and 69.6% had lymphedema. Twelve patients' lymphedema involved only the lower limb(s), 2 the lower and upper limbs, and 2 the lower and upper limbs and face. Nineteen (82.6%) patients were prescribed fluconazole (100 mg/day [n = 8] or 300 mg/week [n = 11]) combined with vitamin E (1,000 mg/day) for a median of 13 months. Responses were complete for 4 (21.1%) patients, partial for 8 (42.1%), and therapeutic failures for 7 (36.8%). CONCLUSIONS: YNS is a rare disease that almost always starts with a chronic cough. Despite inconstant efficacy, fluconazole-vitamin E in combination can be prescribed to treat yellow nails.

Chronic cough: more than just a persistent cough: a systematic literature review to understand the impact of chronic cough on quality of life.

PURPOSE: Chronic cough (CC), defined as a cough persisting ≥ 8 weeks, can have a substantial negative impact on health-related quality of life (HRQoL). This is exacerbated by challenges with timely diagnosis and a lack of approved therapies. A systematic literature review (SLR) was conducted to identify evidence on HRQoL and health state utility values associated with refractory CC or unexplained CC. METHODS: Electronic database searches were supplemented with searches of conference proceedings and health technology assessment body websites. Two independent reviewers assessed all citations for inclusion based on predefined inclusion/exclusion criteria. Key inclusion criteria were patient populations with CC and reporting of patient-reported outcomes or utilities using generic or disease-specific measures. RESULTS: Following screening, 65 studies were identified for inclusion in the SLR. Of these, 23 studies assessed HRQoL among patients with CC who were not treated or treated with unspecified interventions, and 42 studies in patients who were treated with specified interventions. The studies indicated a substantial decrement to HRQoL as a result of CC, characterized by generic and disease-specific patient-reported outcome measures. HRQoL was impacted across multiple domains, including physical, psychological, and social functioning. The studies also demonstrated the potential for treatments to have a significant positive impact on HRQoL. CONCLUSIONS: CC can substantially affect HRQoL in patients, across physical, psychological, and social domains. Although treatments can improve HRQoL in these patients, the available evidence is limited. There remains an unmet need for approved pharmacological treatments to alleviate CC and improve HRQoL for these patients.

Rasch validation of the short form (8 item) PC-QoL questionnaire and applicability of use as a health state classification system for a new preference-based measure.

BACKGROUND: The parent-proxy paediatric chronic cough quality of life questionnaire (PC-QoL) is a commonly used measure of spillover quality of life in parents of children with chronic cough. To date, spillover health utility in these parents is not routinely estimated largely due to the lack of a suitable instrument. Their perspective is not included in economic evaluations of interventions for their children. We explored developing a health state classification system based on the PC-QoL for measuring health utility spill over in this population. METHODS: This study included PC-QoL 8-item responses of 653 parents participating in a prospective cohort study about paediatric chronic cough. Exploratory factor analysis (EFA) and Rasch analysis were used to examine dimensionality and select potential items and level structure. RESULTS: EFA indicated that the PC-QoL had one underlying domain. Rasch analysis indicated threshold disordering in all items which improved when items were collapsed from seven to four levels. Two demonstrated differential item functioning (DIF) by diagnosis or ethnicity and were excluded from the final scale. This scale satisfied Rasch assumptions of local independence and unidimensionality and demonstrated acceptable fit to the Rasch model. It was presented to and modified by an expert panel and a consumer panel. The resulting classification system had six items, each with four levels. DISCUSSION: The PC-QoL can conform to a Rasch model with minor modifications. It may be a good basis for the classification system of a child cough-specific PBM. A valuation study is required to estimate preference weights for each item and to estimate health utility in parents of children with chronic cough.

Burden of Disease Associated with Refractory and Unexplained Chronic Cough in Canada: Results from a National Survey.

INTRODUCTION: Chronic cough (persisting for ≥ 8 weeks) is a common disorder that includes refractory chronic cough (RCC; cough that persists despite treatment of underlying disease) and unexplained chronic cough (UCC; cough with no identifiable cause). We evaluated self-reported health-related quality of life (HR-QoL) and work/activity impairment associated with RCC/UCC in Canada. METHODS: Our exploratory study included Canadians in the Leger Opinion Panel with RCC or UCC. Key entry criteria were ≥ 18 years of age, cough for ≥ 8 weeks, not currently smoking/quit ≥ 1 year ago, no serious respiratory disease or lung cancer, and not taking angiotensin-converting enzyme inhibitors. Respondents completed a 30-min online survey with general and cough-specific HR-QoL questionnaires, including the EuroQol (EQ) visual analogue scale (VAS), EQ-5-dimension 5-level (EQ-5D-5L), cough severity VAS, Leicester Cough Questionnaire (LCQ), and Work Productivity and Activity Impairment-Specific Health Problem (WPAI-SPH). RESULTS: Of 49,076 individuals who completed the chronic cough screening questionnaire (July 30-September 1, 2021), 1,620 (3.3%) met entry criteria for RCC/UCC and 1,046 (2.1%) completed the survey. The mean age of respondents was 45 years and 61% were female. Respondents reported impairments in global HR-QoL (EQ-VAS 73.8, 61% with anxiety/depression on the EQ-5D-5L) and cough-specific HR-QoL (mean cough severity VAS score 29.7, LCQ index 15.2). Work and non-work activities were reduced by 34% and 30%, respectively, on the WPAI-SPH. CONCLUSION: RCC/UCC is prevalent in Canada and associated with impaired HR-QoL, particularly in mental health domains. Additional support and management options may be required to fully address this burden.

The Therapeutic Landscape in Chronic Cough.

In recent years, there has been a substantial increase in the development of antitussive therapies and the first new therapy, gefapixant has been licenced in Europe. This review describes current unlicenced treatments for chronic cough and details treatments currently in development for refractory chronic cough and cough in idiopathic pulmonary fibrosis, as well as compounds previously explored.

Longitudinal Cough Frequency Monitoring in Persistent Coughers: Daily Variability and Predictability.

PURPOSE: We determined the cough counts and their variability in subjects with persistent cough for 30 days. METHODS: The Hyfe cough tracker app uses the mobile phone microphone to monitor sounds and recognizes cough with artificial intelligence-enabled algorithms. We analyzed the daily cough counts including the daily predictability rates of 97 individuals who monitored their coughs over 30 days and had a daily cough rate of at least 5 coughs per hour. RESULTS: The mean (median) daily cough rates varied from 6.5 to 182 (6.2 to 160) coughs per hour, with standard deviations (interquartile ranges) varying from 0.99 to 124 (1.30 to 207) coughs per hour among all subjects. There was a positive association between cough rate and variability, as subjects with higher mean cough rates (OLS) have larger standard deviations. The accuracy of any given day for predicting all 30 days is the One Day Predictability for that day, defined as the percentage of days when cough frequencies fall within that day's 95% confidence interval. Overall Predictability was the mean of the 30-One Day Predictability percentages and ranged from 95% (best predictability) to 30% (least predictability). CONCLUSION: There is substantial within-day and day-to-day variability for each subject with persistent cough recorded over 30 days. If confirmed in future studies, the clinical significance and the impact on the use of cough counts as a primary end-point of cough interventions of this variability need to be assessed.

First Exploration of the Altered Microbial Gut-Lung Axis in the Pathogenesis of Human Refractory Chronic Cough.

PURPOSE: Cough represents a natural mechanism that plays an important defensive role in the respiratory tract, but in some conditions, it may become persistent, nonproductive, and harmful. In general, refractory chronic cough (RCC) occurs in about 20% of individuals; hence, we aimed to assess the presence of altered gut-lung communication in RCC patients through a compositional and functional characterization of both gut (GM) and oral microbiota (OM). METHODS: 16S rRNA sequencing was used to characterize both GM and OM composition of RCC patients and healthy controls (HC). PICRUST2 assessed functional changes in microbial communities while gas chromatography was used to evaluate fecal short-chain fatty acid levels and serum-free fatty acid (FFA) abundances. RESULTS: In comparison with HC, RCC patients reported increased saliva alpha-diversity and statistically significant beta-diversity in both GM and OM. Also, a, respectively, significant increased or reduced Firmicutes/Bacteroidota ratio in stool and saliva samples of RCC patients has been shown, in addition to a modification of the abundances of several taxa in both GM and OM. Moreover, a potential fecal over-expression of lipopolysaccharide biosynthesis and lipoic acid metabolism pathways and several differences in serum FFA levels have been reported in RCC patients than in HC. CONCLUSION: Since differences in both GM and OM of RCC patients have been documented, these findings could provide new information about RCC pathogenesis and also pave the way for the development of novel nutritional or pharmacological interventions for the management of RCC through the restoration of eubiotic gut-lung communication.

Prevalence, clinical characteristics, and disease burden of chronic cough in Italy: a cross-sectional study.

BACKGROUND: Chronic cough has been associated with reduced health-related quality of life, negative impacts on sleep, work, and other daily activities, and increased use of health care resources. Little is known about the prevalence of chronic cough in Italy. In the present study we sought to estimate the prevalence of chronic cough in Italy, describe sociodemographic and clinical characteristics associated with chronic cough, and characterize the impact of chronic cough on overall health and wellness, work and other daily activities, and health care resource use. METHODS: We conducted a cross-sectional study to collect sociodemographic and health-related data from Italian residents who participated in the 2020 National Health and Wellness Survey (N = 10,026). To assess the characteristics and burden of chronic cough, adults who indicated that they had experienced chronic cough during the prior 12 months were compared with propensity score-matched controls without chronic cough. RESULTS: The estimated weighted lifetime and 12-month prevalence of chronic cough were estimated as 9.2% and 6.3%, respectively. Compared with matched controls, respondents with chronic cough had significantly lower measures of overall physical and mental health (P < .001 for both comparisons), and significantly higher rates of anxiety, depression, and sleep disorders (P < .001 for all comparisons). Chronic cough was significantly associated with higher rates of impairment of work and other activities (P < .001 for all comparisons) in the past 7 days, any-cause emergency department visits and hospitalizations in the prior 6 months (P < .001 for both comparisons), and more visits to general and specialist health care providers (P < .001 for both comparisons) in the prior 6 months. CONCLUSIONS: In Italy, chronic cough affects an estimated 3.3 million adults annually and represents a significant burden to individuals and the health care system. TAKE HOME MESSAGE: Little is known about the prevalence of chronic cough in Italy. We found that, in Italy chronic cough represents a significant burden to individuals and the health care system, affecting an estimated 3.3 million adults annually.

How to diagnose GERC more effectively: reflections on post-reflux swallow-induced peristaltic wave index and mean nocturnal baseline impedance.

INTRODUCTION: Post-reflux swallow-induced peristaltic wave index (PSPWI) and mean nocturnal baseline impedance (MNBI) are novel parameters reflect esophageal clearance capacity and mucosal integrity. They hold potential in aiding the recognition of gastroesophageal reflux-induced chronic cough (GERC). Our study aims to investigate their diagnostic value in GERC. METHODS: This study included patients suspected GERC. General information and relevant laboratory examinations were collected, and final diagnosis were determined following guidelines for chronic cough. The parameters of multichannel intraluminal impedance-pH monitoring (MII-pH) in patients were analyzed and compared to explore their diagnostic value in GERC. RESULTS: A total of 186 patients were enrolled in this study. The diagnostic value of PSPWI for GERC was significant, with the area under the working curve (AUC) of 0.757 and a cutoff value of 39.4%, which was not statistically different from that of acid exposure time (AET) (p > 0.05). The combined diagnostic value of AET > 4.4% and PSPWI < 39.4% was superior to using AET > 4.4% alone (p < 0.05). Additionally, MNBI and distal MNBI also contributed to the diagnosis of GERC, with AUC values of 0.639 and 0.624, respectively. AET > 4.4% or PSPWI < 39.4% is associated with a 44% reduction in missed diagnoses of non-acid GERC compared to AET > 6.0% or symptom association probability (SAP) ≥ 95%, and may be more favorable for identifying GERC. CONCLUSION: The diagnostic value of PSPWI for GERC is comparable to that of AET. Combining PSPWI < 39.4% or AET > 4.4% can improve the diagnostic efficiency by reducing the risk of missed diagnoses in cases where non-acid reflux is predominant. Distal MNBI and MNBI can serve as secondary reference indices in the diagnosis of GERC.

Prevalence and disease burden of chronic cough in nine cities of China: an observational study.

BACKGROUND: Chronic cough (CC) is common in the general population of China, creating a difficult-to-ignore public health burden. However, there is a lack of research on the nationwide prevalence and disease burden of CC in the Chinese population. We aim to use an insurance claims database to assess the prevalence and the corresponding economic burden owing to CC in China. METHODS: This was a retrospective observational study based on an administrative medical insurance database in 2015, 2016 and 2017, from nine cities in North, South, East, South-West, and North-West regions of China. The study population was Chinese adults (≥ 18 years old) who had been identified as CC patients. Descriptive data analyses were used in statistical analysis. RESULTS: A total of 44,472, 55,565, and 56,439 patients with mean ages of 53.2 (16.3) years were identified as patients with CC in 2015, 2016, and 2017, respectively. Of these, 55.24% were women. In addition, 8.90%, 9.46%, and 8.37% of all patients in 2015, 2016, and 2017, who had applied for medical insurance, had CC, respectively, with a three-year average probability of 8.88%. The median number of outpatient visits within a calendar year was 27 per year due to any reason during the period of 2015-2017. The median medical cost of each patient per year increased from 935.30 USD to 1191.47 USD from 2015 to 2017. CONCLUSION: CC is common among medical insurance users, with a substantial utilization of medical resources, highlighting the huge burden of CC in China.

Clinical characteristics and effects of inhaled corticosteroid in patients with post-COVID-19 chronic cough during the Omicron variant outbreak.

BACKGROUND: Chronic cough is a common symptom in patients post the coronavirus disease 2019 (COVID-19). In this study, we aimed to investigate the efficacy of inhaled corticosteroids (ICS) and the clinical characteristics of patients with post-COVID-19 chronic cough during the Omicron era. METHODS: An ambispective, longitudinal cohort study was conducted that included patients with post-COVID-19 who attended the respiratory clinic at our hospital between January 1, 2023, and March 31, 2023 with a complaint of persistent cough lasting more than 8 weeks. At 30 and 60 days after the first clinic visit for post-COVID-19 chronic cough, enrolled patients were prospectively followed up. We compared the changes in symptoms and pulmonary function between patients receiving ICS treatment (ICS group) and those not receiving ICS treatment (NICS group) at the two visits. RESULTS: A total of 104 patients with post-COVID-19 chronic cough were enrolled in this study (ICS group, n = 51; NICS group, n = 53). The most common symptoms accompanying post-COVID-19 chronic cough were sputum (58.7%, 61/104) and dyspnea (48.1%, 50/104). Seventy-one (82.6%, 71/86) patients had airway hyperresponsiveness, and 49 patients (47.1%, 49/104) were newly diagnosed with asthma. Most patients (95.2%, 99/104) exhibited improvement at 60 days after the first visit. The pulmonary function parameters of the patients in the ICS group were significantly improved compared to the baseline values (P < 0.05), and the improvement in the FEV1/FVC was significantly greater than that in the NICS group (P = 0.003) after 60 days. CONCLUSIONS: Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) may contribute to the pathogenesis of asthma, which could be the underlying cause of persistent cough post-COVID-19 infection. Post-COVID-19 chronic cough during the Omicron era was often accompanied by sputum, dyspnea, and airway hyperresponsiveness. ICS treatment did not have a significant impact on symptom management of post-COVID-19 chronic cough; however, it can improve impaired lung function in in these individuals.

24 h combined esophageal multichannel intraluminal impedance and pH monitoring in children with chronic cough.

BACKGROUND: Chronic cough in children is closely related to gastroesophageal reflux (GER). However, this association has not been adequately studied due to a lack of diagnostic tools. Combined esophageal multichannel intraluminal impedance and pH (MII-pH) monitoring is considered the most accurate method for evaluating the association between symptoms and reflux, but data on its use in children with chronic cough are still lacking. We aimed to assess the association between chronic cough and GER in children through MII-pH monitoring. METHODS: Children with chronic cough (> 4 weeks) who were suspected gastroesophageal reflux disease(GERD) were selected to undergo 24 h MII-pH monitoring at our hospital. Patients were divided into groups according to their age, body position, reflux index (RI) or total reflux events, and the differences between the groups were analyzed. Then the significance and value of 24 h pH and impedance monitoring in chronic cough and the relationship between chronic cough and reflux were discussed. RESULTS: Overall, 426 patients were included. The median age was 12 months (interquartile range: 6-39.5 months), 129 (30.3%) patients had RI > 7% detected by pH-metry, and 290 (68.1%) patients had positive diagnosis based on the impedance data. GER predominantly occurred in the upright position and mostly involved weakly acidic reflux and mixed gas-liquid reflux. There were 14.1% of children in non-acid GER group were SAP positive showing no difference in acid GER group 13.2% (P = 0.88), whereas patients with SAP > 95% in MII positive group (47[16.2%]) is higher than in MII negative group (P < 0.05). CONCLUSION: Twenty four hour MII-pH monitoring is safe, well tolerated in children, but also has a higher detection rate of gastroesophageal reflux. It can find identify weakly acidic reflux, weakly alkaline reflux and reflux events with different physical properties, which can explain the relationship between GER and chronic cough more comprehensively. It provides new approach for exploring the etiology, diagnosis and treatment of children with chronic cough.

Associations between abnormal sleep behavior and indoor environmental risk factors among children with a chronic cough in Wuxi, China: a cross-sectional study.

BACKGROUND: Indoor environmental factors, such as pet ownership, presence of cockroaches, mattress quality, fuel usage (gas or electricity), use of biomass for cooking and heating, exposure to tobacco smoke or household molds can significantly affect the sleep quality of children with chronic cough. However, data regarding the effects of indoor environmental conditions on sleep in this population are limited. This study aimed to assess the prevalence of abnormal sleep behaviors and to establish associations between indoor environmental factors and sleep behaviors among children with chronic cough in Wuxi, China. METHODS: A cross-sectional design was employed in this study, involving children aged 3-18 years. Data on sociodemographic factors, allergies, home environmental exposures, and sleep characteristics of the participants were collected using paper-based questionnaires. The association between indoor environmental factors and sleep behaviors in children with chronic cough was analyzed using logistic regression models. RESULTS: The findings demonstrated that the prevalence of chronic cough among children in Wuxi was 15.50%. The chronic cough group exhibited a significantly higher incidence of eczema, wheezing, rhinitis, food allergy, and nasosinusitis than the non-chronic cough group. In addition, children with chronic cough also tended to have a family history of sleep disorders and adenoid hypertrophy (P < 0.01). After adjusting for confounding factors, a significant association was observed between bruxism (teeth grinding) and chronic cough (sometimes: odds ratio [OR] = 1.04; confidence interval [CI] = 1.01-1.08; always: OR = 1.11; CI = 1.04-1.19; P < 0.01). Among children with chronic cough, recent home decoration was associated with sleepwalking (OR = 1.04; CI = 1.00-1.07; P < 0.05), mold exposure was associated with bruxism (OR = 1.15; CI = 1.0-1.31; P < 0.05), and carpet use at home was associated with apnea (OR = 1.09; CI = 1.02-1.17; P < 0.05), twitching during sleep (OR = 1.13; CI = 1.00-1.27; P < 0.01) and morning headache (OR = 1.14; CI = 1.05-1.23; P < 0.01). CONCLUSION: Children with chronic cough are more prone to some abnormal sleep behaviors than children without chronic cough. Household decoration within a year, household mold exposure, and carpet use were all significantly positively associated with abnormal sleep behaviors in children with chronic cough. Our study provides novel insights into the impact of the indoor environment on children's sleep and the occurrence of chronic cough, offering guidance for tailored health promotion programs for families.

Manometric Abnormalities in Patients With and Without Chronic Cough.

PURPOSE: This study examines the relationship between chronic cough and vagal hypersensitivity by measuring baseline esophageal motility, with interest in the upper esophageal sphincter (UES). MATERIALS AND METHODS: Patients undergoing workup for dysphagia were assigned to a chronic cough or control group based on self-reported symptoms. Differences in demographics, medical comorbidities, and high resolution esophageal manometry findings were obtained retrospectively. RESULTS: 62.5% of our cohort had chronic cough (30/48). There were no significant differences between the two groups with respect to sex, age, and race/ethnicity. Laryngopharyngeal reflux (LPR) was the only statistically significant predictor of CC (OR 74.04, p = 0.010). Cough patients had upper esophageal sphincter relaxation duration (734 ms) significantly longer than the non-cough patients (582 ms; p = 0.03), though both groups had similar upper esophageal mean basal pressure, mean residual pressure, relaxation time-to-nadir, and recovery time. No significant difference was found in the median intrabolus pressure and UES motility mean peak pressure between groups. CONCLUSION: Subtle differences in high-resolution manometry between patients with and without cough suggest, in line with previous studies, baseline alterations of upper esophageal function may manifest in patients with chronic cough through an undetermined mechanism that may include underlying vagal hypersensitivity. These findings encourage further manometric study examining the relationship between UES dysfunction and chronic cough.

Fluoroscopically measured bronchial collapse in healthy dogs during cough exceeds 25%, and a cutoff of 60% bronchial collapse can be used to distinguish healthy from chronically coughing dogs.

Bronchomalacia, the weakening of bronchial cartilage, is a common cause of cough in dogs. The gold standard for diagnosis of bronchomalacia is bronchoscopy; however, fluoroscopy is often used as a preliminary diagnostic test due to its noninvasiveness. The normal amount of bronchial collapse in healthy dogs using fluoroscopy has not been previously established, with some authors citing <25%. The aims of this prospective and retrospective analytical observational study were to determine the normal amount of airway collapse in healthy animals, the amount of airway collapse in dogs with chronic cough and presumed bronchomalacia, and cut-off values of airway collapse during expiration and cough to distinguish between the two groups. Thoracic fluoroscopy was performed in right and left lateral recumbency during inspiration, expiration, and cough to evaluate the percentage collapse of the trachea and lobar bronchi in 45 healthy and 76 chronically coughing dogs. The bronchi of chronically coughing dogs exhibited a significantly greater amount of collapse during both expiration and cough compared with healthy dogs. Chronically coughing dogs exhibited up to 31.7 ± 26.6% collapse in expiration and 87.5 ± 23.7% collapse during cough, whereas healthy dogs exhibited 14.9 ± 6.1% collapse in expiration and 35.0 ± 13.7% collapse during cough. Based on ROC curves, the authors suggest using cut-off values of 30% during expiration and 60% during cough to distinguish between healthy dogs and those with presumed bronchomalacia. Findings suggest that though healthy dogs can exhibit a greater degree of airway collapse than previously thought, fluoroscopy can be used to distinguish between healthy and presumed bronchomalacic dogs.