Is Chronic Obstructive Pulmonary Disease An Independent Risk Factor For Coronary and Peripheral Atherosclerosis In Heavy Smokers?
Abstract BACKGROUNDThere is a high prevalence of cardiovascular disease (CVD) and atherosclerosis in people with chronic obstructive pulmonary disease (COPD); sharing of risk factors could not be the only cause of the association.OBJECTIVESTo verify whether coronary atherosclerosis and peripheral vascular disease are independently associated with COPD in heavy smokers. We also investigated whether inflammation and poor lung function were related with atherosclerosis findings.METHODSHeavy smokers (≥ 20 pack-years) with COPD (group 1) or normal spirometry (group 2) were recruited. Clinical, laboratory, and anthropometric data were obtained. Main interest variables were prevalence of CCS > 75th percentile (P75), and rates of ABI < 0,9 by Doppler ultrasound. CVD risk was calculated using the Framingham risk score. Serum C-reactive protein (CRP) was measured, and lung function was assessed by spirometry. Differences between groups were compared using parametric and nonparametric tests as adequate.RESULTSWere included 87 patients, 49 with COPD (group 1). The mean ± SD age was 57.2 ± 6.0 years (58.7 ± 5.1 in group 1, 55.2 ± 6.6 in group 2, p=0.006). The mean FEV 1 % was 45.8 ± 17.24 vs. 91.7 ± 15.9 in groups 1 and 2, respectively; p<0.05. The mean smoking index was 48.6 ± 25.4, higher in the COPD group (p=0.037). Stratification by Framingham score yielded a similar distribution in both groups. The frequency of patients with CCS > P75 was 55% vs. 66% in groups 1 and 2, respectively (p=0.823); ABI <9.0 ocurred in 6,3% vs 2,6%, respectivelly ( p=0.555) . CCS and ABI were not associated to FEV 1 %. CRP was inversely associated with VEF 1 ( r s= -0.419; p<0.001), but unrelated to CCS ( r s= 0.136; p=0.265) and ABI ( r s= -0.51; p=0.677).CONCLUSIONSThe studied coronary and peripheral atherosclerosis markers were similar between heavy smokers with COPD and those with normal spirometry. Nor serum CRP neither poor lung function related to CCS or ABI. Our results suggest absence of a independent association between COPD and atherosclerosis.