Patterns of inflammation associated with peripheral arterial disease: the InCHIANTI study.

OBJECTIVE: To determine whether peripheral arterial disease is associated with high circulating levels of pro-inflammatory cytokines, independent of confounders. METHODS: Participants were 955 men and women aged 60 years and older representative of the population in 2 Italian communities (107 with peripheral arterial disease). Measurements included the ankle brachial index, comorbidities, total cholesterol and high-density lipoprotein cholesterol (HDL-C) levels, and these inflammatory factors: albumin, alpha-2 macroglobulin, C-reactive protein, fibrinogen, interleukin (IL)-1beta, IL-1 receptor antagonist, IL-6, IL-6 receptor, IL-10, IL-18, tumor necrosis factor alpha, and transforming growth factor beta. RESULTS: Adjusting for age, sex, body mass index, smoking, comorbidities, HDL-C, and total cholesterol, participants with peripheral arterial disease had higher levels of IL-1 receptor antagonist (147.97 vs 131.24 pg/mL, P = .002), IL-6 (1.65 vs 1.37 pg/mL, P = .026), fibrinogen (362.49 vs 345.50 mg/dL, P = .039), and C-reactive protein (3.18 vs 2.56 mg/dL, P = .043) compared with those without peripheral arterial disease. These associations were attenuated after additional adjustment for physical activity. CONCLUSION: In a community population, peripheral arterial disease is associated with increased circulating levels of IL-6, IL-1 receptor antagonist, fibrinogen, and C-reactive protein compared to persons without peripheral arterial disease. Further study is needed to determine whether reducing levels of certain inflammatory factors lowers the incidence and progression of peripheral arterial disease.

Impairments of muscles and nerves associated with peripheral arterial disease and their relationship with lower extremity functioning: the InCHIANTI Study.

OBJECTIVES: To define the relationships between lower extremity peripheral arterial disease (PAD), pathophysiological findings in lower extremity muscles and nerves, and lower extremity performance. DESIGN: Cross-sectional. SETTING: Two communities in Italy. PARTICIPANTS: Nine-hundred seventy-nine community-dwelling men and women aged 60 and older (109 with PAD). MEASUREMENTS: Presence and degree of lower extremity arterial obstruction were determined using the ankle-brachial index (ABI). Lower extremity muscle cross-sectional area was measured using computed tomography. Peroneal nerve conduction velocity (NCV) and leg power were also determined. Measures of lower extremity functioning were fast walking speed over 4 meters, time required to walk 400 meters, and the summary performance score. RESULTS: Participants with PAD had significantly poorer performance on functional outcomes than participants without PAD. Adjusting for age and sex, presence of PAD was associated with reduced leg muscle power (83.69 vs 103.51 watts, P<.001), reduced muscle cross-sectional area (61.5 vs 63.5 cm2, P=.14), and reduced NCV (43.0 vs 44.2 m/s, P=.003). Adjustment for leg power diminished the independent association between ABI and the functional outcomes measures. CONCLUSION: In community-dwelling individuals, PAD is associated with reduced NCV and reduced muscle power in the lower extremities. Muscle power may mediate the association between lower ABI levels and poorer functional performance.

Knowledge and attitudes regarding cardiovascular disease risk and prevention in patients with coronary or peripheral arterial disease.

BACKGROUND: We compared perceptions regarding risk of cardiovascular events and benefits of cardiovascular disease (CVD) risk factor reduction between patients with peripheral arterial disease (PAD), patients with coronary artery disease (CAD), and patients without atherosclerosis (no disease). METHODS: Participants with no disease (n = 142) had a normal ankle-brachial index and no clinically evident atherosclerosis (group 1). The PAD participants (n = 136) had an ankle-brachial index less than 0.90 and no other clinically evident atherosclerosis (group 2). Participants with CAD (n = 70) had a normal ankle-brachial index and a history of heart disease (group 3). Participants were interviewed regarding risk of mortality, CVD, and the importance of CVD risk factor reduction for hypothetical patients with PAD and CAD. RESULTS: All groups reported that risks of myocardial infarction, stroke, and death were higher for a patient with CAD than for a patient with PAD. Group 2 was less likely than group 3 to believe that PAD is associated with an extremely high risk of stroke (13.3% vs 28.7%; P =.005) or mortality (10.9% vs 26.6%; P =.003). Group 2 was less likely than group 1 to believe that a patient with PAD has a very high risk of myocardial infarction (13.1% vs 23.8%; P =.02), stroke (13.3% vs 27.5%; P =.003), or mortality (10.9% vs 24.3%; P =.004). Compared with group 3, a smaller percentage of patients in group 2 reported that cholesterol lowering was very important in PAD (57.5% vs 75.8%; P =.005). CONCLUSIONS: Compared with other patients, those with PAD underestimated the high risk of cardiovascular events associated with PAD and the benefits of cholesterol-lowering therapy. These findings may help explain the low rates of CVD risk factor control previously reported in patients with PAD.