Clinical Phenotypes of COPD Patients Between in Plateau and Plain

Study Overview
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Brief Summary
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We aimed to collect clinical and radiological data of patients with stable COPD in plateau and plain, and compare the clinical phenotypic characteristics and imaging features of COPD patients in these two areas.

Detailed Description
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The purpose of this study was to investigate the clinical phenotypic characteristics and imaging features of patients with stable chronic obstructive pulmonary disease (COPD) in plateau and plain. We conducted a cross-sectional study, collecting clinical data of stable patients in plateau and plain, and comparing the clinical phenotypic characteristics and imaging features of COPD patients in these two areas.

Official Title
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Clinical and Radiological Phenotypes of Patients With Stable COPD Between in Plateau and Plain

Conditions
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Pulmonary Disease, Chronic Obstructive

Intervention / Treatment
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* Other: No intervention


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: meeting the diagnosis of COPD according to Global Initiative for Chronic Obstructive Lung Disease (GOLD) guidelines and had definite airflow limitation with a post-bronchodilator forced expiratory volume in 1 second (FEV1) / forced vital capacity (FVC)<0.7. Exclusion Criteria: age <40 years; subjects with airway diseases other than COPD; acute exacerbation of COPD in the past 3 months; active tuberculosis; cardiovascular or cerebrovascular events in the past 3 months; cognitive dysfunction such as vascular dementia or Alzheimer's disease; refusal to participate in this study.

Ages Eligible for Study
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Minimum Age: 40 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| COPD patients in the plateau<br>We consecutively enrolled COPD patients visiting the outpatient of Respiratory Medicine at Tibet Autonomous Region People's Hospital from January 2018 to December 2021. | Other: No intervention<br>* No intervention<br>|
| COPD patients in the plain<br>We consecutively enrolled COPD patients visiting the outpatient of Respiratory Medicine at Peking University Third Hospital from January 2018 to December 2021. | Other: No intervention<br>* No intervention<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Assessment of respiratory symptoms | COPD Assessment Test | Data were obtained during the interview. | 
| Exacerbation | Frequency of exacerbations in the past year | Data were obtained during the interview. | 
| Spirometry testing | FEV1 %predicted, FVC %predicted, ratio of FEV1/FVC | Data were obtained during the interview. | 
| Emphysema | The percentage of the LAA divided by total lung volumes (LAA%) was used as an index of the severity of emphysema in quantitative CT examination. | Within 3 months of the interview. | 
| Airway remodeling -1 | Bronchial wall thickness (WT, mm) was used as one of the measurements for assessment of airway remodeling in quantitative CT examination. | Within 3 months of the interview. | 
| Airway remodeling -2 | Luminal area (LA, mm2) was used as one of the measurements for assessment of airway remodeling in quantitative CT examination. | Within 3 months of the interview. | 
| Airway remodeling -3 | Bronchial wall area (WA, mm2) was used as one of the measurements for assessment of airway remodeling in quantitative CT examination. | Within 3 months of the interview. |