Clinical experience suggests that many COPD patients are not diagnosed until they have advanced disease, but there are few epidemiologic data to support this observation. We conducted a comprehensive review of all COPD patients treated by one integrated health system to examine the stage of disease at initial presentation.
The Lovelace Patient Database (upon IRB approval) was used to identify all patients with an inpatient stay (IP), emergency department (ED) or multiple outpatient visits with COPD (ICD codes 491.x, 492.x, 496.x) during 1994 through 2006 yielding 12,491 persons. Claims were extracted for patients with continuous enrollment and without COPD diagnosis prior to spirometry (PFT) yielding the final cohort of 1520 patients. Pulmonary Clinic Laboratory files yielded 648 available PFTs. The stage of COPD was classified based on the percent of predicted FEV1 using the GOLD criteria.
Of the 648 PFTs, 366 confirmed Stage 1 disease or greater. Of these, 71 (19%) were Stage 1; 180 (49%) Stage 2; 96 (26%) Stage 3; and 19 (5%) stage 4 (average FEV1% predicted 60%). The majority of Stage 1 were male (82%)as opposed to other groups where the majorities were female (57%, 70%, and 63%, respectively). The great majority of patients (75%) were 65 years or older at the time diagnosis. Average cigarette pack years for Stage 3 (40) and Stage 4 (48) were greater than for Stage 1 (37) and Stage 2 (36), and those with Stage 3 or 4 were more likely to still be smoking (26%). A pre-test diagnosis of asthma (9%, 18%, 17%, and 5% for Stages 1–4, respectively) was only slightly more common than that of heart failure (14%, 11%, 4%, and 0% for Stages 1–4, respectively).
The great majority of patients (81%) were Stage 2 or greater, and almost one-third were Stage 3 or greater in severity at time of initial COPD diagnosis.
These data support the recommendations of the GOLD committee and others for increased screening for undiagnosed COPD.
Douglas Mapel, University grant monies None; Grant monies (from sources other than industry) None; Grant monies (from industry related sources) None; Shareholder GlaxoSmithKline; Employee Employee of GlaxoSmithKline; Fiduciary position (of any organization, association, society, etc, other than ACCP None; Consultant fee, speaker bureau, advisory committee, etc. None; Other None; No Product/Research Disclosure Information