Statin treated patients have reduced intraplaque angiogenesis in carotid endarterectomy specimens

Treatment with statins is considered a first line therapy in atherosclerotic disease. Intraplaque angiogenesis is involved in plaque progression and instability. It remains unclear whether the beneficial effect of statin treatment in humans is achieved through reduced intraplaque angiogenesis. The aim of this study was to evaluate the capillaries density in carotid plaques removed from patients treated with statin versus untreated patients.

We studied 102 patients who underwent carotid endarterectomy: 98 of them met the inclusion criteria and entered the study; 75 men and 23 women; mean age 66+/-8 years (range 42-83 years). Forty-three patients (44%) were on statin treatment at least 3 months before endarterectomy and 55 (56%) had never received statin treatment. The intensity of intraplaque angiogenesis was evaluated with immunohistochemistry using the antibody CD34. The number of capillaries per mm(2) was measured with a custom designed image tool analysis. With the exception of serum total cholesterol levels and serum low-density cholesterol levels, the two groups of patients did not vary significantly in cardiovascular risk factors and in parameters pertaining to the procedure profile. Patients on statin treatment had less capillaries per mm(2) than patients not receiving this kind of drugs (0.97+/-0.61 per mm(2) versus 1.39+/-0.98 per mm(2), p=0.031). Univariate associations between possible explanatory variables and number of capillaries per mm(2) were tested using Spearman rank R. Variables associated with a p-value <0.20 (age, serum creatinine, serum total cholesterol, serum low-density lipoprotein, serum homocysteine, presence of diabetes mellitus and statin treatment) were entered in a multivariable model. Multivariate analysis showed that statin treatment was the only independent predictor (t=-5.39, p<0.001) of intraplaque angiogenesis.

Statin therapy is associated with reduced intraplaque angiogenesis in the carotid arteries. This could provide an explanation for the beneficial effects of this kind of drug on patients with atherosclerotic disease.