Introduction: Chronic obstructive pulmonary disease (COPD) is a respiratory disease that often goes undiagnosed, particularly in its early stages.
Objective: To examine sociodemographic, general health, and COPD specific factors, including severity of lung obstruction, that are associated with healthcare provider-diagnosed COPD among U.S. adults.
Methods: NHANES cross-sectional data collected from 2007-2012 on adults aged 40-79 years (n=10,219) were analyzed. The primary outcome was self-reported COPD diagnosis with predictive factors analyzed via chi-square and logistic regression analyses.
Results: During 2007-2012, 5.2% of US adults aged 40-79 reported being diagnosed with COPD. Among those diagnosed, 50.8% reported fair or poor health, 47.1% were currently smoking cigarettes, 49.1% were taking prescription respiratory medication, 36.4% had moderate or worse lung obstruction, and nearly 90% had one or more respiratory symptoms. Logistic regression revealed positive associations between receiving a COPD diagnosis and the following: being white (AOR: 3.08, 95% CI: 1.82-5.20); being aged 60-79 years (AOR: 1.65, 95% CI: 1.07-2.53); reporting fair/poor health (AOR: 2.91, CI: 1.55-5.46); having 4-9 (AOR: 3.5, CI: 1.3-9.4) or 10 or more healthcare visits in prior year (AOR: 5.06, CI: 1.62-15.77); being a former (AOR: 1.75, CI: 1.2-2.5) or current smoker (AOR: 1.70, CI: 1.17-2.48); having more severe lung obstruction (AOR: 4.90, CI: 3.28-7.32); having 3 or more respiratory symptoms (AOR: 22.07, CI: 12.03-40.49).
Conclusions: Multiple factors are associated with self-reported COPD diagnosis with number of reported respiratory symptoms having the strongest association. After controlling for other factors, having mild lung obstruction was not associated with being diagnosed.
Keywords: COPD; Diagnosis; NHANES; Prevalence; Smoking; Spirometry.