High-sensitivity C-reactive protein and ankle brachial index in a finnish cardiovascular risk population

High-sensitivity C-reactive protein (hsCRP) has been previously linked to different forms of vascular disease. However, some studies have not found any relationship between hsCRP and atherosclerosis. Also, studies investigating correlation between hsCRP and ankle brachial index (ABI) are scarce. We studied hsCRP in a cardiovascular risk population with a special interest in correlation between hsCRP and ABI. All men and women aged 45 to 70 years from a rural town Harjavalta, Finland were invited to participate in a population survey. Diabetics and people with known vascular disease were excluded. Seventy-three percent (n = 2085) of the invited persons participated and 70% of the respondents (n = 1496) had at least one risk factor to cardiovascular diseases. These subjects were invited to further examinations. From them we measured ABI, hsCRP, leukocyte count, glucose tolerance, systemic coronary risk evaluation (SCORE), body mass index (BMI), and waist circumference. Mean hsCRP was 1.9 mg/L. Smokers had higher hsCRP (mean 2.2 mg/L) than nonsmokers (mean 1.8 mL/L). hsCRP in women was higher than in men (mean 2.0 mg/L versus 1.8 mg/L). Mean ABI was 1.10, and the prevalence of peripheral arterial disease was 3.1%. ABI correlated weakly with hsCRP (r = -0.077, p = 0.014), leukocyte count (r = -0.107, p = 0.001), and SCORE (r = -0.116, p = 0.001). It did not have correlation between age, weight, BMI, or waist circumference. hsCRP correlated with BMI (r = 0.208, p < 0.0001) and waist circumference (r = 0.325, p < 0.0001). When we excluded subjects with hsCRP >10 mg/L, ABI no longer correlated with hsCRP. In a cardiovascular risk population, hsCRP has only a weak correlation with ABI, and this correlation disappeared when we excluded subject with hsCRP >10 mg/L. Instead, hsCRP was correlated to the measures of obesity (waist circumference and BMI), indicating its role as a marker of adipose tissue-driven inflammation. hsCRP does not seem to be a suitable screening method for peripheral arterial disease.