A growing body of evidence suggests that, along with other vascular beds, smoking and chronic obstructive pulmonary disease (COPD) affect the arteries of the lower limbs in terms of the development of peripheral arterial disease (PAD), reported Karsten Keller, MD, of the Johannes Gutenberg-University Mainz (Germany) and his colleagues.

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This provided the rationale for their large database analysis of inpatients with concomitant COPD and PAD. They found that the additional presence of COPD was associated with increased in-hospital mortality in patients with PAD.

“Our data suggest that COPD increased the mortality of PAD patients by the factor 1.2-fold,” they wrote in Respiratory Medicine. “Unexpectedly, this increase was not driven by [myocardial infarction] as the life-threatening acute presentation of [coronary artery disease], but rather related to an increased risk for [pulmonary embolism] and a higher coprevalence of cancer.”

Dr. Keller and his colleagues inspected the German inpatient national database based on ICD codes. They identified 5,611,827 adult inpatients (64.8% men) diagnosed with PAD between January 2005 and December 2015, and of those, 13.6% also were coded for COPD. Overall, 277,894 PAD patients (5.0%) died in the hospital, Dr. Keller and his colleagues wrote.

The all-cause, in-hospital mortality was significantly higher in PAD patients with COPD, compared with those without COPD (6.5% vs. 4.7%, respectively; P less than .001), and cardiovascular events comprising pulmonary embolism (PE), deep vein thrombosis (DVT), and myocardial infarction (MI) occurred more often in coprevalence with PAD and COPD than in PAD without COPD.

In PAD patients, COPD was an independent predictor of in-hospital death (odds ratio, 1.16; 95% confidence interval, 1.15-1.17; P less than .001) as well as an independent predictor for PE (OR, 1.44; 95% CI, 1.40-1.49; P less than .001).

Overall, PAD patients with COPD were of similar age as (73 years), but stayed slightly longer in the hospital than (9 vs. 8 days), those without COPD. PAD patients without COPD revealed more often cardiovascular risk factors like essential arterial hypertension and diabetes, but the prevalence of cardiovascular diseases such as coronary artery disease and heart failure were more often found in PAD patients with COPD. In addition, cancer and renal insufficiency also were more common in PAD patients with COPD, according to the authors.

“Remarkably, PAD patients with COPD showed more frequently lower PAD stages than those without COPD. Especially, PAD stage IV was more prevalent in PAD patients without COPD (19.6% vs. 13.8%; P less than 0.001),” the authors stated. In addition, amputations were more often performed in PAD patients without COPD.

Dr. Keller and his colleagues had the following conclusions regarding the clinical implications of their study: “I) PAD patients with long-standing tobacco use might benefit from COPD screening and treatment. II) PAD patients with additional COPD should be monitored more intensively, and the treatment for COPD should be optimized. III) COPD increases the risk for PE, and it is critical not to overlook this life-threatening disease. IV) MI and PE are important causes of in-hospital death in PAD patients with and without COPD.”

The German Federal Ministry of Education and Research funded the study, and the authors reported having no conflicts.

SOURCE: Keller K et al. Respir Med. 2019 Feb;147:1-6.