Figures
- FIGURE 1
Protocol for detecting early pathological changes related to COPD according to risk factors and comorbidities.This protocol take into account the risk factors for early COPD, and proposes an interval for close follow-up [22, 23, 25, 26, 62–65]. If, by age 35 years, spirometry does not present an obstruction (forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) <0.70) and the patient is truly asymptomatic, spirometry every 5 years is recommended to detect individuals with rapid FEV1 decline that would fit the definition for early COPD [3]. If the patient is symptomatic, further testing with high-resolution computed tomography (HRCT) and/or plethysmography with diffusing capacity of the lung for carbon monoxide (DLCO) or impulse oscillometry (IOS) is recommended to detect early airway trapping, emphysema or diffusion abnormalities prior to spirometric changes. Patients with FEV1/FVC <0.70 at age ≥25 years and FEV1 >80% pred but asymptomatic, should be followed with spirometry every 2 years to detect patients who decline fast. Patients with FEV1/FVC <0.70, FEV1 ≥80% pred and symptomatic should be tested further with HRCT and/or plethysmography with DLCO or IOS to detect early airway trapping, emphysema or diffusion abnormalities and spirometry every 2 years to detect those patients who decline fast in order to initiate early treatment strategies [11, 18, 66]. TB: tuberculosis. *: prematurity/low birth rate, early life infections, maternal smoking, family respiratory history.
- FIGURE 2
Logistic and Cox regression models for forced expiratory volume in 1 s (FEV1) progression and all-cause mortality with the proposed COPDGene 2019 classification of categories. Bold indicated categories where 95% CI did not include 1. Black diamond: exposure; blue diamond: abnormal computed tomography imaging; red diamond: abnormal spirometry; purple diamond: symptoms. #: change in FEV1 assessment done on 4925 participants who returned for phase 2 clinical follow-up; adjusted for age at first visit, sex, race, pack-years, current smoking status and baseline FEV1. ¶: mortality assessment done on 8784 participants in the phase 1 cohort; data are implicitly adjusted for age, additionally adjusted for sex, race, pack-years and current smoking. Reproduced from [18] with permission from the publisher.
Tables
- TABLE 1
Criteria for early detection of COPD
Criteria At-risk population [10, 17, 19] Mild COPD [4, 5] Early diagnosis of COPD [15] Early COPD [3] Symptoms Cough, dyspnoea, phlegm Dyspnoea 0–1 mMRC, CAT <10 points N/A N/A Exposure At least 10 pack-years cigarette smoke or biomass exposure [10, 20] At least 10 pack-year cigarette smoke or biomass exposure At least 10 pack-year cigarette smoke At least 10 pack-year cigarette smoke Age years N/A N/A N/A <50 Progression to COPD ∼30–40% [10, 19, 20] N/A N/A Currently in study Time to COPD diagnosis 5 years Spirometry FEV1/FVC ratio Normal <0.7 <0.7 <LLN FEV1 decline mL·year−1 Variable [10, 19, 20] N/A N/A >60 FEV1 Normal Normal N/A N/A CT scan >50% CT evidence of emphysema or airway wall thickening [10] N/A N/A Visual emphysema, air trapping or bronchial thickening FEV1: forced expiratory volume in 1 s; FVC: forced vital capacity; CT: computed tomography; mMRC: modified Medical Research Council; CAT: COPD Assessment Test; N/A: not applicable; LLN: lower limit of normal.
- TABLE 2
Predictive accuracy of questionnaires externally validated and measured against post-bronchodilator forced expiratory volume in 1 s/forced vital capacity (FEV1/FVC) <0.70
Questionnaire Score Sensitivity % Specificity ROC AUC COPD Diagnostic Questionnaire (CDQ) [35] >16.5 80–91 24–49 0.65–0.73 Lung Function Questionnaire (LFQ) [36] ≤18 88 25 0.65 COPD Population Screener (COPD-PS) [37] ≥5 79 35 0.57–0.70 PUMA Score (Primary Care/PLATINO) [38] ≥5 81.8–88.6/46.7–56.2 33.5–41.8/79.8–83.3 0.70–0.73/0.67–0.70 CAPTURE+PEF [39] >2 75.5 93.1 0.93 PEF L·min−1 Male ≤350 Female ≤250 ROC AUC: receiver operating characteristic area under the curve; PUMA: Prevalence Study and Regular Practice, Diagnosis and Treatment, Among General Practitioners in Populations at Risk of COPD in Latin America; PLATINO: Proyecto LatinoAmericano de Investigación en Obstrucción Pulmonar (COPD research project in Latin America); CAPTURE: COPD Assessment in Primary Care To Identify Undiagnosed Respiratory Disease and Exacerbation Risk; PEF: peak expiratory flow.
