Clinical Features and Airways Inflammation in Never Smokers and Smokers With COPD

Browse trials for

• Pulmonary Disease, Chronic Obstructive 5,520
• Airway Obstruction 147
• Inflammation 3,536
• Smoking 1,509

Keywords

• COPD
• smoking
• induced sputum
• clinical features

Pulmonary Disease, Chronic Obstructive

5,520 studies on the registry are indexed under Pulmonary Disease, Chronic Obstructive; 856 are open to participants now.

This study's enrollment of 68 is below the median of 158 across 1,497 observational studies indexed under Pulmonary Disease, Chronic Obstructive.

Lead sponsor

Ministry of Scientific Research, Tunisia is the lead sponsor of 2 studies on the registry; none are open to participants now.

Study population

Groups and cohorts

• Healthy subjects

  Healthy non-smoking subjects were never smokers with normal spirometry and did not have a history of lung disease or chronic respiratory symptoms. Information about respiratory symptoms and comorbidities were collected. Healthy subjects underwent pulmonary function tests (Spirometry). Induced sputum was collected to determine total and differential inflammatory cells counts as well as inflammatory mediators (Interleukin-8 and tumor necrosis factor-alpha).

  Diagnostic Test: Analysis of induced sputum · Diagnostic Test: Lung Function test · Diagnostic Test: Enzyme-linked Immunosorbent Assay

• COPD Never smokers

  Never smokers referred to subjects who had never smoked Airflow limitation in COPD was defined as a post-bronchodilator forced expiratory volume in 1 second (FEV1) to forced vital capacity (FVC) ratio \<70% and FEV1 reversibility of \<12% and 200 mL from baseline values after inhalation of 400 µg of Salbutamol. Information about respiratory symptoms and comorbidities were collected. Never smoking subjects with COPD underwent pulmonary function tests (Spirometry). Induced sputum was collected to determine total and differential inflammatory cells counts as well as inflammatory mediators (Interleukin-8 and tumor necrosis factor-alpha).

  Diagnostic Test: Analysis of induced sputum · Diagnostic Test: Lung Function test · Diagnostic Test: Enzyme-linked Immunosorbent Assay

• COPD Smokers

  Smokers were defined as persons who had smoked \> 20 packs of cigarettes in a lifetime and who continue smoking every day. Airflow limitation in COPD was defined as a post-bronchodilator forced expiratory volume in 1 second (FEV1) to forced vital capacity (FVC) ratio \<70% and FEV1 reversibility of \<12% and 200 mL from baseline values after inhalation of 400 µg of Salbutamol. Information about respiratory symptoms and comorbidities were collected. Smoking subjects with COPD underwent pulmonary function tests (Spirometry). Induced sputum was collected to determine total and differential inflammatory cells counts as well as inflammatory mediators (Interleukin-8 and tumor necrosis factor-alpha).

  Diagnostic Test: Analysis of induced sputum · Diagnostic Test: Lung Function test · Diagnostic Test: Enzyme-linked Immunosorbent Assay

Interventions

• Diagnostic testAnalysis of induced sputum

  Induced sputum was collected and analysed in the three arms (Healthy subjects, Never smokers with COPD and smokers with COPD) The volume of the sputum sample, was treated with an equal volume of 0.1% dithiothreitol. The samples were then vortexed and placed in a shaking water bath at 37°C for 15 min to ensure complete homogeneisation. The suspensions were centrifuged at 400× g and the sputum supernatant stored at -80°C until cytokines analysis. The cell pellet was resuspended in 0.5% bovine serum albumin in phosphate buffered saline and cytospin were made by putting 100 µL of the cell suspension in the funnels. Slides for differential cell counts were stained with May-Grünwald Giemsa.

• Diagnostic testLung Function test

  All the subjects underwent pulmonary function tests (Healthy subjects, Never smokers with COPD and smokers with COPD). Pulmonary function parameters were measured using a portable spirometer (Easy One ndd. Medizintechnik; Zurich, Switzerland) according to the ATS criteria (American Thoracic Society). Reversibility test was performed 15 min after inhalation of 400 µg of Salbutamol (Ventolin, GlaxoSmithKline, Middlesex, UK). All spirometry data were graded for quality and only tests that met high quality scores were used for the final analysis.

  Also known as: spirometry

• Diagnostic testEnzyme-linked Immunosorbent Assay

  IL-8 and TNF-α were measured in the sputum supernatant of all the subjects (Healthy subjects, Never smokers with COPD and smokers with COPD). Commercially available kits were used to detect IL-8 (Human IL-8 Immuno-Biological Laboratories ELISA Kit) and TNF-α (Human TNF-alpha Sigma-Aldrich ELISA Kit) concentrations in the sputum supernatants. The absorbance was measured at 450 nm. The lower limits detection were 2 pg/mL for IL-8 and 5 pg/mL for TNF-α. The intra assay coefficients of variability were 8.7% for IL-8 and 7.7% for TNF- α.

  Also known as: ELISA

Primary outcomes

1. Weight measurement

   Weight was measured in kilograms for all the participants.

   Time frame: 6 months

2. Height measurement

   Height was measured in meters for all the participants.

   Time frame: 6 months

3. Forced vital capacity (FVC)

   FVC was measured using a portable spirometer (Easy One ndd. Medizintechnik; Zurich, Switzerland) according to the American Thoracic Society criteria.

   Time frame: 6 months

4. Forced expiratory volume in one second (FEV1)

   FEV1 was measured using a portable spirometer (Easy One ndd. Medizintechnik; Zurich, Switzerland) according to the American Thoracic Society criteria.

   Time frame: 6 months

5. Sputum induction and collection

   Sputum induction was conducted by inhalation of nebulised sterile hypertonic saline solution followed by coughing and expectoration of airway secretions. For nebulisation, an ultrasound nebulizer was used for 5-20 min to provide an adequate amount of sample. The subject is asked to cough and expectorate at 5 min intervals.

   Time frame: 6 months

Secondary outcomes

1. BMI determination

   Weight and height values were combined to report BMI in kg/m2

   Time frame: 6 months

2. Tiffeneau ratio (FEV1/FVC)

   The calculation of FEV1/FVC allows the identification of obstructive ventilatory defect. A FEV1/FVC \< 70 % where FEV1 is reduced more than FVC signifies an obstructive defect.

   Time frame: 6 months

3. Sputum cell counts

   Four hundred non-squamous cells were counted by two technicians and the mean of the two scores was expressed as percentage of the total cell count. Sputum samples containing \>20% of squamous cells and/or with cell viability \<70% were excluded from analysis.

   Time frame: 1 month

4. Sputum supernatant analyses

   IL-8 and TNF-α sputum supernatant concentrations were measured in the sputum supernatant of the three studied groups using ELISA test.

   Time frame: 3 months

Individual participant data

Plan to share: Yes — All IPD that underlie results will be shared in a publication

Supporting information: Study protocol, Clinical study report

Time frame: The data will become available when the article will be accepted by the editorial board of the journal.