A Study to Evaluate the Accuracy of Primary Care Diagnosis Using Oscillometry and Fractional Exhaled Nitric Oxide for Asthma and COPD Versus Specialist Diagnosis in Patients With Suspected Asthma or COPD
试验速览
- 阶段
- 不适用
- 状态
- 招募中
- 发起方
- AstraZeneca
- 入组人数
- 600
- 试验地点
- 12
- 主要终点
- Accuracy of primary care asthma/COPD diagnosis using oscillometry (ALDS: R5, R20, R5-R20, X5, Ax) plus FeNO ≥50 ppb (Fenom PRO®/ALDS Pro) vs specialist gold standard; metrics: Cohen's kappa, agreement, sensitivity, specificity in overall, asthma, COPD
研究概览
简要总结
Current diagnostic methods for asthma and chronic obstructive pulmonary disease mostly depend on pulmonary function tests, especially spirometry. While spirometry is a foundational tool, its diagnostic accuracy is often limited by the patient's ability to perform forceful breathing maneuvers, as well as technical and reproducibility challenges, and the need for proper equipment and training. These constraints can compromise effective diagnosis of asthma and COPD in primary care settings. Prompt and accurate diagnosis by primary care physicians is essential for better patient outcomes. Although variable airflow limitation often measured as a change in FEV1 after bronchodilator is a hallmark of asthma, inconsistencies in test quality and reversibility criteria create challenges in distinguishing asthma from COPD. These complexities highlight the need for alternative diagnostic tools beyond traditional spirometry.
This observational study is designed to evaluate the diagnostic accuracy and technical feasibility of using oscillometry and FeNO testing in primary care for suspected asthma and COPD, compared to conventional specialist-based diagnostics. The study will be conducted across 6 countries in the MEA, Asia, and Latin America, with two hospital sites per country. Primary care physicians will be trained in oscillometry and FeNO testing using standardized protocols and tools such as the Ambulatory Lung Diagnosis System following GINA and GOLD guidelines. Eligible patients will provide consent, complete a history and symptom questionnaire, and undergo primary care-based assessment for a provisional diagnosis. If specialist assessment cannot occur the same day, it will be done within three days. No follow-up visits are planned. Study outcomes will inform the feasibility and accuracy of integrating these methods into routine care, aiming to improve the early and reliable diagnosis of asthma and COPD.
详细描述
Diagnosis of asthma and chronic obstructive pulmonary disease (COPD) currently relies heavily on pulmonary function tests (PFTs), with spirometry as the core method. However, the effectiveness of spirometry is closely linked to patients' ability to perform maximal, forceful breathing maneuvers. This poses difficulties for individuals with varying physical capacities, leading to challenges in test use, result interpretation, and reproducibility. Such limitations often require skilled specialists, which may not be available in all settings, especially in primary care.
Primary care providers are the initial interface for patients with respiratory symptoms, tasked with rapidly evaluating and diagnosing conditions during brief patient interactions. Early diagnosis of asthma and COPD is crucial, yet spirometry standards-such as those set by the European Respiratory Society and American Thoracic Society-often cannot be met in primary care due to resource and expertise constraints. Operational barriers, including equipment costs, maintenance, staff training, and integration into routine practice, further hinder widespread adoption of spirometry.
Adding to the complexity, variable bronchodilator responsiveness complicates the differential diagnosis of obstructive airway diseases. Traditional reversibility criteria based on FEV1 changes following bronchodilator administration may be unreliable, reducing their diagnostic utility for distinguishing asthma from COPD and highlighting the need for multidimensional approaches.
Oscillometry is emerging as a promising alternative or adjunct to spirometry. It is a non-invasive method capable of detecting airway resistance and reactance, which can reveal early functional changes in asthma and COPD-even before clinical symptoms appear. Oscillometry is valuable for monitoring disease progression, assessing bronchodilator response, and may be more sensitive for small airway dysfunction, especially in patients with normal or slightly impaired lung function.
Measurement of fractional exhaled nitric oxide (FeNO) is another innovative technique. As a marker for T-helper 2 cell-mediated airway inflammation, FeNO can enhance the diagnosis and monitoring of asthma. Guidelines recommend FeNO thresholds for diagnosis and management, adding an objective layer to clinical decision-making. International guidelines advise integrating FeNO and additional objective tests, such as eosinophil counts, with standard PFTs to support asthma diagnosis.
研究设计
- 研究类型
- Observational
- 观察模型
- Cohort
- 时间视角
- Prospective
入排标准
- 年龄范围
- 18 Years 至 —（Adult, Older Adult）
- 性别
- All
- 接受健康志愿者
- 否
入选标准
- •Patients are eligible to be included in the study if all the following criteria apply and after providing written informed consent:
- •Suspected asthma (asthma group)
- •Patients ≥ 18 years old or with legal age of consent in the jurisdiction in which the study is taking place, at the time of signing the ICF.
- •Patients presenting with symptoms of wheezing, cough, chest tightness, shortness of breath, but without a clinically confirmed diagnosis of asthma.
- •Suspected COPD (COPD group)
- •Patients ≥ 40 years old at the time of signing the ICF.
- •Patients presenting with symptoms of dyspnea, chronic cough or sputum production, but without a clinically confirmed diagnosis of COPD.
排除标准
- •Patients are excluded from the study if any of the following criteria apply:
- •Prior diagnosis of COPD or asthma.
- •Use of ICS in the last 6 months or use of oral corticosteroids in the last 3 months.
- •Any diseases that influence lung function result such as lung cancer, pneumonia, active pulmonary tuberculosis, pulmonary embolism, and interstitial lung disease.
- •Any history of recent surgery that affects lung function results, including but not limited to thoracotomy surgery, pneumothorax surgery, and thoracic drainage.
- •Contraindication to spirometry or oscillometry test, or allergy to bronchodilator.
- •Currently pregnant or breast-feeding women.
- •If the investigator judges that the patient is unlikely to comply with study procedures, restrictions, and requirements.
结局指标
主要结局
Accuracy of primary care asthma/COPD diagnosis using oscillometry (ALDS: R5, R20, R5-R20, X5, Ax) plus FeNO ≥50 ppb (Fenom PRO®/ALDS Pro) vs specialist gold standard; metrics: Cohen's kappa, agreement, sensitivity, specificity in overall, asthma, COPD
时间窗: 1 to 3 days
Primary care diagnosis uses a diagnostic algorithm combining oscillometry and FeNO. Oscillometry: Ambulatory Lung Diagnosis System (ALDS) parameters-respiratory system resistance at 5 Hz (R5), resistance at 20 Hz (R20), difference R5-R20, reactance at 5 Hz (X5), and area of reactance (Ax). FeNO: measured with Fenom PRO® or ALDS Pro devices, using a diagnostic cut-off of ≥50 ppb. Specialist care diagnosis is the comparator: Gold Standard Specialist Care Diagnosis established through standard clinical practice, including pulmonary function tests, spirometry, physiological tests, imaging, laboratory tests, and bronchial provocation tests. Accuracy will be quantified using Cohen's Kappa coefficient, Percentage Agreement, Sensitivity, and Specificity. The analysis will be conducted in the overall population, the asthma group, and the COPD group.
次要结局
- accuracy and agreement between asthma or COPD diagnoses made in primary care with provisional diagnoses derived exclusively from patient history compared to specialist settings diagnosis(1 to 3 days)