Genetics likely also important, but no genetic marker has been identified
23 sept 2009-- Inflammatory markers are consistently associated with lower extremity peripheral arterial disease (PAD) and particular outcomes, but are not necessarily causally associated; and, although genetics may play an important role, no genetic marker has been associated with the disease, according to a review in the Sept. 29 issue of the Journal of the American College of Cardiology.
Mary M. McDermott, M.D., and Donald M. Lloyd-Jones, M.D., from Northwestern University in Chicago note that patients with lower extremity PAD have higher levels of inflammatory biomarkers, including C-reactive protein, interleukin-6, tumor necrosis factor-alpha and soluble adhesion molecules, and that the biomarkers are associated with adverse outcomes such as adverse calf skeletal muscle characteristics and cardiovascular mortality.
The reviewers observed that statin treatment is beneficial in PAD patients, possibly due to statins' ability to reduce inflammation, although clinical trials examining whether treatments that affect inflammatory biomarkers improve outcomes have not been done. An estimated 20 to 45 percent of PAD risk is attributed to genetics, but the authors note that a consistent genetic marker has not yet been identified.
"Despite the consistent associations of elevated inflammatory biomarkers with adverse outcomes in PAD, there are insufficient data to conclude that inflammatory biomarkers are causally related to adverse outcomes in PAD," the authors conclude. "Similarly, insufficient data exist to support targeting PAD patients who have higher levels of inflammation with more intensive secondary prevention therapies, such as antiplatelet therapies or statins."