A Cross-sectional Study to Measure Cough in Severe Asthma
Condition: Asthma; Cough
MeSH terms: Asthma; Cough
Study type: Interventional

Summary: 
      This study aims to characterise cough in severe asthma through an observational
      cross-sectional analysis of patients stratified by inflammatory biomarker profile using a
      number of subjective and objective cough measurement tools.
    

Detailed description: 
      This study will use a combination of subjective and objective cough measures to assess the
      frequency of cough as well as its related morbidity in severe asthmatics. Comparisons will be
      made between T2-High, T2-Low and T2-intermediate patients defined using a composite biomarker
      profile (blood eosinophil count and FeNO) to assess the role of cough in each and these
      results will be compared to the transcriptomic and proteomic measurements in the RASP-UK
      where the same biomarker profiling is being used to define clinical sub-groups of severe
      asthma. This study aims to also improve characterisation of the T2-Low population and
      identify possible mechanisms for the pathophysiology of this group.

      60 patients are expected to be recruited to the study. Patients will be provided with an
      information sheet and have a telephone follow-up after at least 24 hours to ask if they
      remain interested in participation and if so, they will then be asked back for a baseline
      visit.

      Three groups of severe asthmatics will be recruited (as described in appropriate section) and
      undergo the following procedures:

        -  Demographic details, height, weight, spirometry, FeNO and vital signs

        -  Patient reported outcomes:

             -  Asthma Mini-Asthma Quality of Life Questionnaire (mini-AQLQ) - abbreviated version
                of Juniper AQLQ

             -  Asthma Control Questionnaire (ACQ-5 (5 questions);

             -  Leicester Cough Questionnaire, the Cough-specific quality-of-life Questionnaire and
                Cough Hypersensitivity Questionnaire will be used to assess the impact of cough;

             -  Visual analogue scales (VAS) for cough (VASc) and urge to cough (VASu) will be used
                as a measure of cough severity.

        -  Blood samples - a sample of blood will be taken for whole blood transcriptomic and serum
           analyses

        -  Citric acid cough challenge test will be used to measure cough reflex sensitivity in
           each phenotype.

        -  Spontaneous sputum sample - if patients produce a sputum sample during spirometry or
           citric acid challenge, this will be recorded and the sample will be retained for sputum
           differential cell count and storage of processed soluble components.

        -  On completing the above procedures, patients will be asked to wear a validated
           ambulatory cough monitor (Leicester Cough Monitor) for a 24-hour period to assess the
           frequency of cough and if they agree, will be fully instructed in its use.

      Patients will be asked to attend a follow-up visit 2 weeks after baseline. The study
      procedures will remain the same as visit 1 with the exception of collection of clinical
      samples.

      A mild/moderate population will be recruited and undergo the same procedures as the severe
      group in a baseline visit. No mild/moderate asthmatics will be asked to attend for a
      follow-up visit.
    

Intervention name(s): Citric acid; Leicester Cough monitor; fractional exhaled nitric oxide testing (FeNO); Patient reported outcome measures
Intervention type(s): Drug; Device; Other; Other
Intervention description(s): Citric Acid cough challenge to be administered to assess the cough reflex sensitivity in patients; Ambulatory cough monitor to assess cough frequency over a 24 hour period; Measurement of exhaled nitric oxide to give an indication of airway inflammation; A number a patient reported outcome measures will be administered including: Asthma control questionnaire (ACQ-5), mini Asthma Quality of Life Questionnaire (mini AQLQ), Leicester Cough Questionnaire (LCQ), Cough Quality of Life Questionnaire (CQLQ), Cough Hypersensitivity Questionnaire (CHQ) and visual analogue scales for severity og cough (VASc) and Urge to Cough (VASu)
Intervention MeSH terms: Nitric Oxide; Citric Acid; Sodium Citrate
Allocation: Non-Randomized
Intervention model: Single Group Assignment
Masking: None (Open Label)
Primary purpose: Other