Background: Individuals with chronic obstructive pulmonary disease (COPD) are at increased risk of cardiovascular diseases, osteoporosis, and muscle wasting. Systemic inflammation may be involved in the pathogenesis of these disorders. A study was undertaken to determine whether systemic inflammation is present in stable COPD. Methods: A systematic review was conducted of studies which reported on the relationship between COPD, forced expiratory volume in 1 second (FEV 1 ) or forced vital capacity (FVC), and levels of various systemic inflammatory markers: C-reactive protein (CRP), fibrinogen, leucocytes, tumour necrosis factor-a (TNF-a), and interleukins 6 and 8. Where possible the results were pooled together to produce a summary estimate using a random or fixed effects model. Results: Fourteen original studies were identified. Overall, the standardised mean difference in the CRP level between COPD and control subjects was 0.53 units (95% confidence interval (CI) 0.34 to 0.72). The standardised mean difference in the fibrinogen level was 0.47 units (95% CI 0.29 to 0.65). Circulating leucocytes were also higher in COPD than in control subjects (standardised mean difference 0.44 units (95% CI 0.20 to 0.67)), as were serum TNF-a levels (standardised mean difference 0.59 units (95% CI 0.29 to 0.89)). Conclusions: Reduced lung function is associated with increased levels of systemic inflammatory markers which may have important pathophysiological and therapeutic implications for subjects with stable COPD.

Background-Chronic obstructive pulmonary disease (COPD) increases the risk of cardiovascular disease 2-to 3-fold.The factors responsible for this association remain largely unknown. Methods and Results-We analyzed data from participants, Ն50 years of age, of the Third National Health and Nutrition Examination Survey (nϭ6629) to determine whether C-reactive protein (CRP) and other systemic inflammatory markers are present in participants with chronic airflow obstruction and are associated with cardiac injury. Participants with severe airflow obstruction had circulating leukocyte, platelet, and fibrinogen levels that were 460/L (95% confidence interval [CI], 30 to 890/L), 39 510/L (95% CI, 21 730 to 57 290/L), and 41.63 mg/dL (95% CI, 19.87 to 63.39 mg/dL) higher, respectively, than in those without airflow obstruction. They were also 2.18 times (95% CI, 1.46 to 3.27) more likely to have an elevated circulating CRP level. Moderate airflow obstruction was associated with smaller but still significant increases in these levels. Moderate and severe airflow obstruction was associated with increased occurrence of ischemic changes on electrocardiograms of participants. In the presence of both highly elevated CRP and moderate or severe airflow obstruction, the Cardiac Infarction Injury Score was 2.68 and 5.88 U higher, respectively, than in those without airflow obstruction and with low CRP, which suggests an additive effect of CRP and COPD on the risk of cardiac injury. Conclusion-Low-grade systemic inflammation was present in participants with moderate to severe airflow obstruction and was associated with increased risk of cardiac injury. This may in part explain the high rates of cardiovascular complications in COPD.

No abstract

Chronic obstructive pulmonary disease and other disorders, associated with reduced lung function, are strong risk factors for cardiovascular events, independent of smoking. Overall, when the lowest quintile of lung function, as measured by FEV1 is compared with the highest quintile, the risk of cardiovascular mortality increases by approximately 75% in both men and women. Having symptoms of chronic bronchitis alone increases the risk of coronary deaths by 50%. Reduced ratio of FEV1 to FVC by itself is a modest independent risk factor for coronary events, increasing the risk by 30%. However, if patients have ventricular arrhythmias, the risk of coronary events is increased twofold, suggesting that the cardiotoxic effects of obstructive airways disease are amplified in those who have underlying cardiac rhythm disturbances. In general, for every 10% decrease in FEV1, all-cause mortality increases by 14%, cardiovascular mortality increases by 28%, and nonfatal coronary event increases by almost 20%. These data indicate that chronic obstructive pulmonary disease is a powerful, independent risk factor for cardiovascular morbidity and mortality.