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Screening for Chronic Obstructive Pulmonary Disease: Evidence Report and Systematic Review for the US Preventive Services Task Force.

IMPORTANCE
Chronic obstructive pulmonary disease (COPD) is the third leading cause of death in the United States.


OBJECTIVE
To systematically review literature on the accuracy of screening questionnaires and office-based screening pulmonary function testing and the efficacy and harms of treatment of screen-detected COPD.


DATA SOURCES
MEDLINE, PubMed, and the Cochrane Central Register of Controlled Trials for relevant English-language studies published through January 2015.


STUDY SELECTION
Two reviewers independently screened abstracts and studies. The search yielded 13,141 unique citations; 465 full-text articles were reviewed, and 33 studies met the inclusion criteria.


DATA EXTRACTION AND SYNTHESIS
Two reviewers rated the quality of each study using USPSTF criteria.


MAIN OUTCOMES AND MEASURES
Diagnostic accuracy (sensitivity, specificity, positive predictive value [PPV], and negative predictive value [NPV]; treatment efficacy (COPD exacerbations, all-cause mortality, quality of life, and dyspnea); and treatment harms.


RESULTS
All screening questionnaires were based on symptoms as well as risk factors such as age and smoking history. The COPD Diagnostic Questionnaire was the most extensively studied (5 studies, n = 3048), with moderate overall performance for COPD detection: area under the receiver operating characteristic curve (AUC), 0.65 to 0.72; sensitivity, 80% to 93%; and specificity, 24% to 49%, at a threshold of greater than 16.5. Positive predictive value and NPV ranged from 17% to 45% and 76% to 98%, respectively. For pulmonary function-based screening tools, FEV1/FEV6 was the best studied (3 studies, n = 1587), with AUC ranging from 0.84 to 0.85. Sensitivity ranged from 51% to 80%. Specificity (range, 90%-95%) and PPV (range, 63%-75%) appeared better than questionnaires. There was not strong evidence to support that screening and supplying smokers with spirometry results improves smoking cessation rates. Treatment trials were unavailable for screen-detected patients. Trials that reported outcomes in patients with mild to moderate COPD included 2 trials of long-acting β-agonists (LABAs) (n = 3174), 1 RCT of LABAs and inhaled corticosteroids (ICS) (n = 1097), 5 RCTs of the long-acting muscarinic antagonist tiotropium (n = 4592), and 6 RCTs of ICS (n = 3983). They suggested no benefit in all-cause mortality, but a decrease in annual rates of exacerbations with pharmacologic treatments. Few trials reported harms for any individual drug class. Adverse effects were generally mild (eg, dry mouth and cough).


CONCLUSIONS AND RELEVANCE
There was no direct evidence available to determine the benefits and harms of screening asymptomatic adults for COPD using questionnaires or office-based screening pulmonary function testing or to determine the benefits of treatment in screen-detected populations. Indirect evidence suggests that the COPD Diagnostic Questionnaire has moderate overall performance for COPD detection. Among patients with mild to moderate COPD, the benefit of pharmacotherapy for reducing exacerbations was modest.