Association of COPD with carotid wall intima-media thickness in vascular surgery patients

SummaryIntroductionThere is increasing evidence that non-invasive imaging modalities such as ultrasonography may be able to detect subclinical atherosclerotic lesions, and as such may be useful tools for risk-stratification. However, the clinical relevance of these observations remains unknown in patients with COPD. Therefore we investigated the association between COPD and carotid wall intima-media thickness (IMT) in patients undergoing vascular surgery and its relationship with mortality in these patients.MethodsCarotid wall IMT was measured in 585 patients who underwent lower extremity, aortic aneurysm or stenosis repair. Primary study endpoint was increased carotid wall IMT which was defined as IMT≥1.25mm. Secondary study endpoints included total and cardiovascular mortality over a mean follow-up of 1.5 years.ResultsThirty-two percent of patients with mild COPD and 36% of the patients with moderate/severe COPD had increased carotid wall IMT, while only 23% had an increased carotid wall IMT in patients without COPD (p<0.01). COPD was independently associated with an increased carotid wall IMT (OR 1.60; 95% CI 1.08–2.36). Among patients with COPD, increased carotid wall IMT was associated with an increased risk of total (HR, 3.18 95% CI 1.93–5.24) and cardiovascular mortality (HR 7.28, 95% CI 3.76–14.07).ConclusionsCOPD is associated with increased carotid wall IMT independent of age and smoking status. Increased carotid wall IMT is associated with increased total and cardiovascular mortality in patients with COPD suggesting that carotid wall measurements may be a good biomarker for morbidity and mortality in these patients

The obesity paradox in patients with peripheral arterial disease

Background: Cardiac events are the predominant cause of late mortality in patients with peripheral arterial disease (PAD). In these patients, mortality decreases with increasing body mass index (BMI). COPD is identified as a cardiac risk factor, which preferentially affects underweight individuals. Whether or not COPD explains the obesity paradox in PAD patients is unknown. Methods: We studied 2,392 patients who underwent major vascular surgery at one teaching institution. Patients were classified according to COPD status and BMIs (ie, underweight, normal, overweight, and obese), and the relationship between these variables and all-cause mortality was determined using a Cox regression analysis. The median follow-up period was 4.37 years (interquartile range, 1.98 to 8.47 years). Results: The overall mortality rates among underweight, normal, overweight, and obese patients were 54%, 50%, 40%, and 31%, respectively (p < 0.001). The distribution of COPD severity classes showed an increased prevalence of moderate-to-severe COPD in underweight patients. In the entire population, BMI (continuous) was associated with increased mortality (hazard ratio [HR], 0.96; 95% confidence interval [CI], 0.94 to 0.98). In addition, patients who were classified as being underweight were at increased risk for mortality (HR, 1.42; 95% CI, 1.00 to 2.01). However, after adjusting for COPD severity the relationship was no longer significant (HR, 1.29; 95% CI, 0.91 to 1.93). Conclusions: The excess mortality among underweight patients was largely explained by the overrepresentation of individuals with moderate-to-severe COPD. COPD may in part explain the "obesity p