Prospective Study on the Evaluation, Patient Reported Outcomes and Effectiveness of Treatment for Chronic Cough

Completed

• Conditions: Chronic Cough
• Interventions: Other: Usual clinical practice

• Registration Number: NCT04758351
• Lead Sponsor: McMaster University

Brief Summary

Chronic cough is a common troublesome symptom which has a global prevalence of approximately 10%, but with wide variations across continents. The aim of this study is to evaluate the effectiveness of treatment, patient-reported outcomes and burden of disease in patients with chronic cough referred to a specialist clinic. The proposed study will use pre-defined diagnostic criteria, investigations and treatment algorithms such that all recruited patients will undergo the same investigations and follow a set management algorithm. This study will objectively and subjectively assess coughing at baseline and after treatment in a real-world clinical setting. This will allow us to understand the relationship between any objective reduction in cough after treatment, and whether this translates to any significant improvement in subjective questionnaire scores. We will assess the impact of health conditions on lost productivity in monetary units and assess the amount of absenteeism, presenteeism and daily activity impairment attributable to unexplained chronic cough/refractory chronic cough. Finally, a patient survey at the end of the study will evaluate the patients' satisfaction and experience of investigation, management trials and use of questionnaires.

Detailed Description

This is a prospective observational single-center study of patients referred to secondary care for investigation and management of explained chronic cough, refractory chronic cough, and unexplained chronic cough. The study will have 4 research visits integrated between standard clinical visits. Patients will be recruited from secondary care clinics. Patient eligibility will be assessed against the study inclusion/exclusion criteria and patients will undergo informed consent in the research centre. Subjects who provide informed consent and are enrolled in the study will undergo screening procedures.

At Visit 1 (screening) data on demographics and medical history will be collected and a complete physical examination will be conducted. Subjects will undergo skin prick testing and spirometry and complete self-reported questionnaires (Leicester Cough Questionnaire, Valuation of Lost Productivity, Work Productivity, Activity, and Impairment, Healthcare Resource Utilization, Reflux Disease Questionnaire, Sino-Nasal Outcome Test, and Global Rating of Change Scale). Subjects will be fitted with a 24-hour cough monitor.

At Visit 2, the 24-hour cough monitor will be removed. Subjects will undergo blood sampling, methacholine challenge, sputum induction, and provide a urine sample.

Between Visits 2 and 3, physicians will provide a single clinical treatment pathway to address the most likely cause of chronic cough. Treatment for chronic cough will be in line with current clinical practice guidelines published by the European Respiratory Society Taskforce on Chronic Cough. Treatment plans will range from 2 weeks to 3 months.

Visit 3 will occur 2 weeks to 3 months following subjects' second clinical visit. Subjects will complete self-reported questionnaires (Leicester Cough Questionnaire, Valuation of Lost Productivity, Work Productivity, Activity, and Impairment, Reflux Disease Questionnaire, Sino-Nasal Outcome Test, and Global Rating of Change Scale) and be fitted with a 24-hour cough monitor.

At Visit 4 the 24-hour cough monitor will be removed. Subjects will undergo blood sampling, sputum induction, and provide a urine sample. Subjects will complete a patient satisfaction survey.

All study procedures will be performed according to local standard operating procedures and be conducted by trained and experienced staff with supervision by medical doctors. Safety will be assessed throughout the study by monitoring for adverse events and serious adverse events.

Study Timeline

• Study First Submitted: 2021-02-05
• Study First Submitted QC: 2021-02-16
• Study First Posted: 2021-02-17
• Study Start: 2021-12-14
• Status Verified: 2024-09
• Primary Completion: 2025-04-30
• Study Completion: 2025-04-30
• Last Update Submitted: 2025-05-05
• Last Update Posted: 2025-05-06

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 100

Inclusion Criteria

1. Aged ≥18-75
2. Patients referred to a specialist primarily with a history of chronic cough (cough lasting >8 weeks)
3. Normal Chest X-ray
4. No Evidence of Airflow Obstruction

Exclusion Criteria

1. Subjects who are currently established on treatment and their chronic cough is well controlled.
2. Unable to perform acceptable and reproducible spirometry.
3. Current smoker or ex-smoker with ≥20 pack-year smoking history and abstinence of ≤6 months
4. Symptoms of upper respiratory tract infection in the last 1 month which have not resolved
5. Lower respiratory tract infection or pneumonia in the last 1 month
6. Asthma exacerbation in the previous month requiring an increase or start of an inhaled corticosteroid or oral corticosteroid
7. Significant other primary pulmonary disorders in particular; pulmonary embolism, pulmonary hypertension, lung cancer, cystic fibrosis, significant radiologically proven emphysema, interstitial lung disease or bronchiectasis.
8. Any centrally acting medication within the last 2 weeks which in the view of the investigator could influence the coughing. Any participant who is taking amitriptyline, dextromethorphan, pregabalin, gabapentin or opioids will not be eligible to take part in this study unless they are willing and medically able to withdraw from such medication before the start of visit 1. The reason for this is that centrally-acting medications may influence coughing rates at baseline.
9. History of psychiatric illness, drug or alcohol abuse which may interfere in the participation of the trial.
10. Positive Covid-19 test within 2 weeks of screening visit.

Study & Design

• Study Type: OBSERVATIONAL
• Study Design: Not specified

Arm && Interventions

Group	Intervention	Description
Cases - Patients with chronic cough	Usual clinical practice	Patients referred to secondary care clinic for investigation and treatment for explained chronic cough, refractory chronic cough, and unexplained chronic.

Primary Outcome Measures

Name	Time	Method
Changes in objective cough frequency	3 months	Change in objective cough frequency pre- and post-treatment among patients referred to secondary care for treatment of explained chronic cough, refractory chronic cough, and unexplained chronic cough.

Secondary Outcome Measures

Name	Time	Method
Measure the relationship between objective cough frequency and work productivity and activity	3 months	Measure the post treatment relationship between objective cough frequency and work productivity and activity among patients referred to secondary care for treatment of explained chronic cough, refractory chronic cough, and unexplained chronic cough. Work productivity and activity is measured using the Work Productivity and Activity Impairment Questionnaire which is a 6-item self-administered questionnaire used to assess productivity and impairment because of a specific health problem such as chronic cough.
Correlation in change of quality of life and healthcare utilization	3 months	Correlation between pre- and post-treatment change in quality of life and Healthcare Related Utilization among patients referred to secondary care for treatment of explained chronic cough, refractory chronic cough, and unexplained chronic cough. Quality of life is measured using the Leicester Cough Questionnaire. The Leicester Cough Questionnaire is a 7 point Likert scale with a minimum value of 1 indicating chronic cough impacts participant life all of the time and a maximum value of 7 indicating chronic cough impacts participant life none of the time. Healthcare utilization is measured by recording the number of visits to family physician, outpatient specialist, number of tests, and medication use.
Patient satisfaction	3 months	Patient satisfaction measurements of clinical investigations, treatment, and use of questionnaires among patients referred to secondary care for treatment of explained chronic cough, refractory chronic cough, and unexplained chronic cough. Patient satisfaction will be measured using a 5 point Likert scale where the minimum value is 1 indicating participants were very unsatisfied and the maximum value is 5 indicating participants were very satisfied.
Comparison of change in objective cough frequency and participant perceived change in condition	3 months	Comparison of pre- and post-treatment change in objective cough frequency and perceived change in condition among patients referred to secondary care for treatment of explained chronic cough, refractory chronic cough, and unexplained chronic cough. Perceived change in condition is measured using the Global Rating of Change Scale which is a 15 value scale. The Global Rating of Change Scale is a 15 point scale with a minimum value of -7 indicating a worse outcome and a maximum value of +7 indicating a better outcome.
Measure the relationship between objective cough frequency and lost productivity	3 months	Measure the post treatment relationship between objective cough frequency and lost productivity among patients referred to secondary care for treatment of explained chronic cough, refractory chronic cough, and unexplained chronic cough. Lost productivity is measured using the Valuation of Lost Productivity questionnaire which contains a series of questions that evaluate the impact of functional impairment on productivity loss, not just for the individual but also on the work environment.
Correlation in change of objective cough frequency and work productivity and activity	3 months	Correlation between pre- and post-treatment change in objective cough frequency and work productivity and activity among patients referred to secondary care for treatment of explained chronic cough, refractory chronic cough, and unexplained chronic cough. Work productivity and activity is measured using the Work Productivity and Activity Impairment Questionnaire which is a 6-item self-administered questionnaire used to assess productivity and impairment because of a specific health problem such as chronic cough.
Correlation in change of quality of life and lost productivity	3 months	Correlation between pre- and post-treatment change in quality of life and lost productivity among patients referred to secondary care for treatment of explained chronic cough, refractory chronic cough, and unexplained chronic cough. Quality of life is measured using the Leicester Cough Questionnaire. The Leicester Cough Questionnaire is a 7 point Likert scale with a minimum value of 1 indicating chronic cough impacts participant life all of the time and a maximum value of 7 indicating chronic cough impacts participant life none of the time. Lost productivity is measured using the Valuation of Lost Productivity questionnaire which contains a series of questions that evaluate the impact of functional impairment on productivity loss, not just for the individual but also on the work environment.
Correlation in change of quality of life and work productivity and activity	3 months	Correlation between pre- and post-treatment change in quality of life and work productivity and activity among patients referred to secondary care for treatment of explained chronic cough, refractory chronic cough, and unexplained chronic cough. Quality of life is measured using the Leicester Cough Questionnaire. The Leicester Cough Questionnaire is a 7 point Likert scale with a minimum value of 1 indicating chronic cough impacts participant life all of the time and a maximum value of 7 indicating chronic cough impacts participant life none of the time. Work productivity and activity is measured using the Work Productivity and Activity Impairment Questionnaire which is a 6-item self-administered questionnaire used to assess productivity and impairment because of a specific health problem such as chronic cough.
Correlation in change of objective cough frequency and healthcare utilization	3 months	Correlation between pre- and post-treatment change in objective cough frequency and Healthcare Related Utilization among patients referred to secondary care for treatment of explained chronic cough, refractory chronic cough, and unexplained chronic cough. Healthcare utilization is measured by recording the number of visits to family physician, outpatient specialist, number of tests, and medication use.
Correlation in change of objective cough frequency and lost productivity	3 months	Correlation between pre- and post-treatment change in objective cough frequency and lost productivity among patients referred to secondary care for treatment of explained chronic cough, refractory chronic cough, and unexplained chronic cough. Lost productivity is measured using the Valuation of Lost Productivity questionnaire which contains a series of questions that evaluate the impact of functional impairment on productivity loss, not just for the individual but also on the work environment.
Comparison of change in objective cough frequency and quality of life	3 months	Comparison of pre- and post treatment change in objective cough frequency and quality of life among patients referred to secondary care for treatment of explained chronic cough, refractory chronic cough, and unexplained chronic cough. Quality of life is measured using the Leicester Cough Questionnaire. The Leicester Cough Questionnaire is a 7 point Likert scale with a minimum value of 1 indicating chronic cough impacts participant life all of the time and a maximum value of 7 indicating chronic cough impacts participant life none of the time.

Trial Locations

Locations (1)

Imran Satia; 🇨🇦 Hamilton, Ontario, Canada