Pulmonary Disease,Chronic Obstructive; Clinical Trial
Official title:
Evaluation and Treatment of Small Airways in COPD
Chronic obstructive pulmonary disease (COPD) is a common disease , and characterized by
progressive development of airflow limitation. Small airway disease (obstructive bronchitis)
and lung parenchyma damage (emphysema) are the main mechanisms of chronic airflow
limitation. Research shows that small airway resistance increased by 4-40 times in COPD
patients, and become the main part of the airflow obstruction. Impulse oscillation system
(IOS) is able to measure the total airway resistance, the central airway resistance and the
peripheral airway resistance, which is now widely used to assess small airway function in
COPD patients. While High resolution CT (HRCT) is easy to operate and its images are
intuitive. Meanwhile it can measure the proportion of emphysema, the airway diameter and the
thickness of airway wall. Both of these two tests have great significance in small airway
evaluation. Chronic obstructive pulmonary disease with acute exacerbation (AECOPD) is an
acute onset process, which is characterized by the aggravation of respiratory symptoms and
deterioration of pulmonary function. However, the structural and functional changes of small
airway in AECOPD are not clear. Inhalation drugs are the main treatment for stable COPD ,
and inhaled corticosteroid（ICS）+long-acting beta2-agonist（LABA） are used to treat patients
with severe and severe airflow limitation. The particles in traditional inhalation drugs are
larger and mainly deposited in large airways, and their effects on small airway function are
relatively small.
The objectives of the investigators study are COPD patients. The study is divided into two
parts, that is the part of AECOPD patients and the part of stable patients . Patients with
AECOPD are arranged to take HRCT and IOS test to assess the small airway changes.Patients
with stable COPD are randomized to take either beclomethasone / formoterol (particle
diameter for 1.4-1.5um) or budesonide / formoterol (3.2um) for three months. The structure
and function changes of small airway in different stage will be evaluated and the efficacy
of these two drugs is to be compared. This study is expected to highlight the investigators
understanding on the role of small airways in COPD, and provide a guideline to clinical
standardized treatment as well as evaluation of patients' conditions.
The COPD patients in the investigators hospital are selected to participate in the
investigators study, and strict inclusion and exclusion criteria are to be complied with.
All the subjects will be told the details of the study and sign the informed consent before
inclusion.HRCT will be used to evaluate the structure of small airway by measuring the
thickness of the third stage branches of apical segmental bronchus in the right upper lobe
(WT). R5-R20 measured by IOS will be used to assess small airway resistance.
The study is divided into two parts, that is the part of AECOPD patients and the part of
stable patients . Both of them have three steps .
Part 1. AECOPD patients:
- Subjects screening : To inquire the history of the disease and to take the IOS and
Bronchial dilation test.
- Baseline data collection：patients will be arranged to complete a series of
questionnaires, as well as HRCT, IOS, pulmonary function test and 6 minute walk test.
- Test stage：During their hospital stay, the patients are to be treated with oxygen
inhalation and different kinds of drugs, and the patients will followed up for three
weeks after discharge. Completing the examinations and questionnaires at each time
visit ,and another CT scan at the last visit.
Part 2. Stable COPD patients:
- Subjects screening : To inquire the history of the disease and to take the IOS and
Bronchial dilation test.
- Baseline data collection：In the two-week washout period，patients are only allowed take
salmeterol/fluticasone 50:250ug 2 times daily, and stop the use of other inhalation
drugs and oral glucocorticoid. At the end of this period, complete a series of
questionnaires, as well as HRCT, IOS, pulmonary function test and 6 minute walk test.
- Test stage： patients are randomized to take either beclomethasone / formoterol (100:6ug
2inhalations twice daily ) or budesonide / formoterol (160:4.5ug 2inhalations twice
daily) for three months.Completing the examinations and questionnaires at the end of
each month, another CT scan at the last visit.
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Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Parallel Assignment, Masking: Open Label, Primary Purpose: Treatment