C-reactive protein, atherosclerosis and kidney function in hypertensive patients

Previous studies have shown a relationship between coronary or carotid atherosclerosis and C-reactive protein (CRP) concentrations. In the present investigation, we evaluated the relationship between high-sensitivity CRP (hsCRP) concentrations and the presence of atherosclerotic lesions in the renal arteries and/or abdominal aorta. In 95 hypertensive patients who underwent intra-arterial DSA on suspicion of renovascular disease, blood was sampled during the procedure for measurement of hsCRP. The presence of atherosclerotic lesions was assessed at the level of the renal arteries and the abdominal aorta. Haemodynamically significant renal artery stenosis was diagnosed when 50% or more stenosis was observed. Patients with fibromuscular disease (n = 8) or incomplete data (n = 4) were excluded from analysis. The results revealed that the median hsCRP concentrations were significantly higher among the 57 patients with atherosclerosis of the aorta and/or renal arteries compared to those in the 26 patients without any angiographic lesions (4.6 vs 1.7 mg/l; P < 0.005). Moreover, in patients with renal artery stenosis, levels of hsCRP were higher when the degree of stenosis exceeded 50%. However, the association between hsCRP and the presence of atherosclerosis appeared to be confounded by serum creatinine, creatinine clearance, age and gender. In the whole group a significant inverse relationship was found between creatinine clearance and hsCRP (P < 0.05). In conclusion, hsCRP concentrations are related to atherosclerotic lesions in the renal arteries and the abdominal aorta. While this supports the view that atherosclerotic renal artery stenosis is part of a systemic inflammatory vascular disease, increased concentrations of CRP may also coincide with decreased renal function.