True prevalence of COPD and its association with peripheral arterial disease in the internal medicine ward of a tertiary care hospital

OBJECTIVES: The primary objective was to determine the prevalence of confirmed chronic obstructive pulmonary disease (COPD) in patients aged 45 years or more who were admitted to the internal medicine ward of our tertiary care hospital (HFR Fribourg, Switzerland), and were either "tagged" as having COPD or at risk for COPD. The secondary objective was to determine the prevalence of the association of COPD with peripheral artery disease (PAD) in this population. METHODOLOGY: We evaluated all consecutive patients aged >= 45 years, admitted to our internal medicine ward between November 2013 and March 2014. All patients with a diagnosis of COPD, chronic bronchitis and/or lung emphysema in their electronic medical record ("tagged" as COPD) were evaluated for inclusion, as well as patients with at least one classic symptom and one classic risk factor for COPD identified by them on a check-list (patients at risk for COPD). Spirometry, and measurement of anklebrachial index (ABI) and toe-brachial index when necessary, were performed in each patient once they were clinically stable. RESULTS: One hundred and seventy-two of 888 consecutive patients were included. COPD was found in 81 patients. Amongst the 75 patients tagged as COPD, 65 (87%) were actually suffering from COPD and 10 (13%) carried a false diagnosis. COPD was diagnosed in 16 (16%) of the 97 at-risk patients. PAD was identified in 35 (43%) of patients suffering from confirmed COPD and in 22 (24%) of patients without COPD. There was a significant association between COPD and PAD (p <0.01). CONCLUSION: COPD was identified in 9% of the 888 patients evaluated. The majority of patients tagged as COPD were accurately diagnosed and a substantial proportion of at-risk patients were underdiagnosed. A significant association between COPD and PAD was found. In smokers, spirometry showing COPD is a useful test to detect patients at higher cardiovascular risk. Thus, we suggest that screening for PAD using an ABI should be proposed to every smoker with confirmed COPD.