Cigarette smoking is the most prominent risk factor for chronic obstructive pulmonary disease (COPD) and peripheral arterial disease (PAD). Prevalence of COPD among cigarette smokers is about 23% in Poland. Effort dyspnea which develops in advanced stage of COPD is the leading cause of seeking medical advice. Physical activity among patients with PAD is reduced due to intermittent claudication. It may cause delayed COPD diagnosis in this group of patients.
The aim of the study: To estimate the prevalence of COPD among patients suffering from severe PAD who were hospitalized in surgery department due to critical limb ischemia and to evaluate difficulties during COPD diagnosis in this group of patients.
Material and methods: We examined 64 patients suffering from severe PAD (at least IIb stage according to Fontaine's scale). Patients were asked about the typical symptoms of COPD: chronic cough, regular sputum production and dyspnea. To evaluate the intensity of dyspnea we used British Medical Research Council scale. Spirometry was performed to every patient. Patients with airways obstruction underwent spirometry after the administration of inhaled bronchodilator. Every patient who had the post-bronchodilator value of FEV,/FVC ratio below the lower limit of normal values was diagnosed with COPD.
Results: It was not possible to evaluate the dyspnea intensity using MRC scale in 44% of 34 patients who reported dyspnea. During the study we diagnosed 16 patients with COPD (9 pts had 1st stage of COPD according to GOLD classification, 7 pts--2nd). 9 patients had been formerly diagnosed with COPD (2 pts--1st stage, 5 pts--2nd, and 2 pts--3rd). Spirometry-defined COPD was present in 39% of study group. The analysis of data from patients with PAD coexistent COPD revealed that 60% of them were current cigarette smokers and 28% of them declared passive smoking exposure. The other known negative prognostic factors in patients with COPD such as BMI lower than 21 kg/mr2, FEV1% of predicted value below 65% and X-rays photograph visible emphysema were observed in 40%, 32% and 12% of patients with PAD and coexistent COPD respectively. Hypertension was present in 52% of patients with PAD and coexistent COPD, cardiac arterial disease in 52% and chronic heart failure due to cardiac arterial disease in 36%. Further analysis of laboratory tests revealed dyslipidemia and chronic kidney disease in 52% and 60% of these patients respectively.
Conclusions: COPD diagnosis among patients suffering from severe PAD involves several difficulties such as uselessness of MRC dyspnea scale and frequent heart diseases which delay the COPD diagnosis being considered as primary dyspnea reason. Many factors which have been proven to be responsible for worse prognosis due to COPD were observed in patients with PAD and coexistent COPD. High prevalence of COPD among patients suffering from PAD suggests the spirometry as a COPD screening would be justified in that group.