Cough in interstitial lung disease

What causes cough in pulmonary fibrosis, and how should we treat it?

PURPOSE OF REVIEW

To review the current understanding of the impact, mechanisms and treatments for cough in patients with interstitial lung disease (ILD). Evidence suggests that cough is a prevalent symptom in patients with ILD and has a significant impact on patients.

RECENT FINDINGS

There is increasing interest in the role of cough hypersensitivity as seen in chronic refractory cough in patients with ILD, and encouraging recent results suggest that ILD-associated cough responds to opiate therapy.

SUMMARY

Understanding the aetiology of cough in patients with ILD is crucial to continue to develop therapies which might be effective in reducing cough and increasing quality of life.

Study of nasal mucosa histopathological changes in patients with hypersensitivity pneumonitis

Hypersensitivity pneumonitis (HP) is an interstitial lung disease that develops after inhalation of a variety antigens in susceptible individuals. The nasal mucosa is constantly exposed to these antigens that can irritate the respiratory mucosa. So, the purpose of this study was to study nasal histopathological changes in order to identify any shared pathological changes between the upper airways and the well-known pathological features of HP. 40 HP patients diagnosed at the Chest Department, Kasr Alainy hospital following ATS/JRS/ALAT guidelines were included. Patients were subjected to thorough history, high-resolution computed tomography, spirometry, cough evaluation test (CET), sinonasal outcome test-22 (SNOT-22), sinonasal examination and nasal mucosal biopsy by an otolaryngologist under visualization by a rigid nasal endoscope. The mean age of the patients was 46.2 ± 13.5 (85% were females and 15% were males). 90% of patients presented with cough and the mean CET was 17.15 ± 5.59.77.5% of patients suffered from sinonasal symptoms and the mean SNOT-22 was 12.18 ± 3.8. There was a significant correlation between the burden of sinonasal symptoms represented by the SNOT-22 and the severity of the cough represented by CET (r 0.40, p 0.01). 87.5% of HP patients had chronic inflammation of the nasal mucosa with predominant lymphocytic infiltration in 72.5% of patients. 77.5% of HP patients had a high burden of sinonasal symptoms which is positively associated with cough severity. 72.5% of patients had predominately lymphocytic infiltration of the nasal mucosa.Trial registration: retrospectively registered, registration number is NCT05723796, date of registration 13/02/2023.

Management of cough in patients with idiopathic interstitial lung diseases in primary care

Importance: Cough is a common symptom in idiopathic interstitial lung diseases (ILDs), there is little information of its management in primary care. The objective of this study was to explore the frequency of cough-related consultations and the medications prescribed to patients with ILDs in primary care. Methods: This retrospective cohort study used electronic medical records (EMR) from Manitoba primary care providers participating in the Manitoba Primary Care Research Network repository (2014–2019). Cough-related consults and the subsequent medications prescribed to patients with ILDs were identified in the EMR. Results: 295 patients with ILDs were identified, 73 (25%) of them had 141 cough-related consultations (mean 1.9, SD 1.3) during the period studied. In 50 (35%) of the consultations, patients were prescribed one or more of the following: inhaled bronchodilators (34%), nasal corticoids (18%), codeine/opiates (18%), antibiotics (14%), inhaled corticoids (14%), proton pump inhibitors (8%), cough preparations (6%), antihistamines (4%), and oral corticoids (2%). 13 (26%) subsequent cough-related consultations were identified within 6 months, mainly among patients who were prescribed cough preparations, nasal corticoids, antihistamines, and antibiotics. Conclusion: One-quarter of patients with ILDs consulted primary care due to cough, and about a third of them received a prescription to address potentially underlying causes of cough. Although further studies are required to explore the effect of the medications prescribed, recurrent cough consultations suggested that cough preparations, nasal corticoids, and antihistamines are among the least effective treatments. More research is needed to understand the causes and optimal treatment of cough in patients with ILDs.

Antitussive Effect of a Chest Band in Patients with Interstitial Lung Disease: The Preliminary Results from a Pre-post Intervention Study

Objective Evidence supporting the efficiency of clinically administered therapies against interstitial lung disease (ILD)-related cough is limited. Thus, we conducted a study to evaluate the efficacy of short-term use of chest bands on cough in patients with ILD. Methods This pre-post intervention study was performed at two university hospitals between April 2017 and August 2020. Scores of the visual analog scale (VAS) for cough severity (in terms of frequency and intensity), Leicester Cough Questionnaire (LCQ)-acute, and frequency scale for symptoms of gastroesophageal reflux disease (FSSG) were assessed before and after the use of the chest band (24/48 hours). Patients The study included patients with idiopathic interstitial pneumonias (IIPs) or connective tissue disease-associated interstitial lung disease (CTD-ILD). Results Four patients with IIPs and seven with CTD-ILD were included in the analysis. The cough intensity and LCQ-acute total score improved significantly after the use of the chest band (p=0.007 and p=0.005, respectively), although the cough frequency showed no significant reduction (p=0.074). Furthermore, the FSSG total and acid-reflux symptom scores improved (p=0.018 and p=0.027, respectively), and a negative correlation between the change in LCQ-acute total score and that in FSSG score for acid-reflux symptoms was observed (Spearman rho =-0.841, p=0.001). Conclusion The results of the current study suggest that chest bands might be useful for treating chronic refractory cough in patients with ILD and gastroesophageal reflux disease. However, these results should be interpreted with caution due to methodological limitations associated with this study.

Sputum quantitative cytometry in patients with interstitial lung disease and chronic cough

BACKGROUND

Chronic cough frequently occurs in patients with diffuse interstitial lung diseases (ILDs), and can have negative effects on quality-of-life. While there are multiple possible contributors to cough in this setting, the contribution and consequences of airway inflammation have not been previously measured. We aimed to estimate the prevalence of airway cellular inflammation in patients with chronic cough and ILD, and examine the interaction between airway inflammation and changes in lung function.

METHODS

We examined all patients with physician-diagnosed ILD and chronic cough who had sputum quantitative cytometry ordered between 2004 and 2018. The prevalence of airway inflammation was estimated by applying previously established criteria for bronchitis. FEV₁ and FVC were compared between individuals based on the presence of airway inflammation. The changes in FEV₁ and FVC were compared between individuals who had their treatment tailored to their sputum result, and those who did not.

RESULTS

Airway inflammation was present in 50% of patients (n = 173), and was associated with lower FEV₁ (1.87 vs 2.05 L, p = 0.043) and FVC (2.39 vs 2.71, p = 0.024). Sputum-guided management of airway eosinophilia was associated with improvements in FEV₁ (+120 vs -205mL, p < 0.0001) and stability of FVC (+13 vs -284mL, p = 0.003).

CONCLUSIONS

Airway inflammation is common in patients with chronic cough and ILD, and its presence may negatively affect lung function. Further research is required to understand if there is a role for quantitative sputum cytometry in this population, particularly if sputum-guided management of airway inflammation could lead to improvements in cough and other ILD outcomes.

Clinical significance of self-reported cough intensity and frequency in patients with interstitial lung disease: a cross-sectional study

Background

The intensity and frequency of cough remain unclear in interstitial lung disease (ILD). The aim of this study was to evaluate the intensity and frequency of cough in idiopathic interstitial pneumonias (IIPs), connective tissue disease-associated interstitial lung disease (CTD-ILD), and chronic hypersensitivity pneumonia (CHP), and examine their associations with clinical indices.

Methods

In this cross-sectional study, the intensity and frequency of cough were evaluated using a 100-mm visual analogue scale. Scores on the Leicester Cough Questionnaire, chronic dyspnoea scale, and a frequency scale for symptoms of gastro-oesophageal reflux disease (FSSG) were collected. The correlations of cough intensity and frequency with potential predictor variables were tested using bivariate and multiple logistic regression analysis.

Results

The study included 70 patients with IIPs, 49 with CTD-ILD, and 10 with CHP. Patients with IIPs had the most severe cough intensity among the three patient groups. In patients with IIPs, both the intensity and frequency of cough were negatively associated with the diffusing capacity of the lung for carbon monoxide and positively with the Composite Physiologic Index (CPI). In CTD-ILD, both the intensity and frequency of cough were correlated with a higher FSSG score. In multivariate analysis of patients with ILD, IIPs and the FSSG score were independently associated with both components of cough, and CPI tended to be independently associated with cough frequency. Finally, we examined the features of the differences between cough intensity and frequency in all patients with ILD. Patients in whom cough frequency was predominant had a greater impairment of health status relative to other patients.

Conclusions

Cough intensity was greater in IIPs than in other ILDs. Different clinical indices were associated with patient-reported cough intensity and frequency according to the subtype of ILD. Cough frequency was more strongly associated with health status than was cough intensity. These findings suggest that medical staff could manage patients with ILD by considering cough-related factors when assessing the intensity and frequency of cough.

Implementing an interstitial lung disease clinic improves survival without increasing health care resource utilization

BACKGROUND

Multidisciplinary collaboration is the cornerstone of interstitial lung disease (ILD) care. Delayed access to specialized care is associated with worse outcome. At the same time, the economic burden of ILD is high. We hypothesized that the establishment of a regional, dedicated ILD clinic would improve survival, but without necessarily causing an increase of health care resource utilization (HRU).

METHODS

A historic cohort (January 2000-June 2013, n = 127) and a specialized care cohort followed by a dedicated ILD clinic (July 2013-June 2016, n = 144) were compared. Patients with idiopathic pulmonary fibrosis were excluded, due to the impact of new anti-fibrotic agents. Patients' data were linked to multiple provincial health administrative datasets. HRU included hospitalizations, doctor and emergency visits, pulmonary (including chest x-ray, chest CT scans, pulmonary function tests, bronchoscopies), cardio-vascular investigations, and specific ILD therapies. HRU was calculated as annual rate by domain. Three-year survival from initial assessment was the secondary outcome.

RESULTS

The 2 cohorts were closely comparable in terms of specific ILD diagnosis, baseline lung function, comorbidities, neighbourhood income. There were overall no significant differences in terms of HRU. In the specialized care cohort, the use of non-steroid immunosuppressive therapies increased and survival significantly improved, despite significantly older age of patients at the time of initial assessment. Specialized ILD care was independently protective towards survival.

CONCLUSIONS

Specialized, multi-disciplinary ILD care in a dedicated regional clinic is associated with improved survival and does not cause an increase of HRU, supporting the institution of potentially more cost-effective care with specialized ILD clinics.