Simvastatin attenuates plaque inflammation: evaluation by fluorodeoxyglucose positron emission tomography

Abstract

Objectives: We investigated whether simvastatin attenuates plaque inflammation by using 18F-fluorodeoxyglucose positron emission tomography (18FDG-PET) co-registered with computerized tomography.

Background: Inflammation plays a key role in progression and destabilization of atherosclerotic plaque. 18F-fluorodeoxyglucose PET is a promising tool for visualizing inflammation of atherosclerotic plaque. Antiinflammatory action is one of the pleiotropic effects of statins.

Methods: Forty-three consecutive subjects, who underwent 18FDG-PET for cancer screening and had 18FDG uptakes in the thoracic aorta and/or the carotid arteries, were randomized to either statin group receiving simvastatin (n = 21) or diet group receiving dietary management only (n = 22). The maximum standardized uptake values (SUVs) were measured in individual plaques, and were averaged for analysis of the subjectwise results. The responses were assessed after 3-month treatments.

Results: Positron emission tomography revealed 117 and 123 18FDG-positive plaques in the statin and diet groups, respectively. Simvastatin, but not diet alone, attenuated plaque (18)FDG uptakes and decreased the SUVs (p < 0.01). Simvastatin reduced low-density lipoprotein cholesterol (LDL-C) by 30% (p < 0.01) and increased high-density lipoprotein cholesterol (HDL-C) by 15% (p < 0.01), whereas LDL-C and HDL-C levels were not changed in the diet group. In the statin group, the decrease in the SUV was well correlated with the HDL-C elevation (p < 0.01) but not with the LDL-C reduction.

Conclusions: 18F-fluorodeoxyglucose PET visualized plaque inflammation and simvastatin attenuated it. The LDL-C-independent effects of simvastatin may participate in the beneficial effect. 18F-fluorodeoxyglucose PET has a potential for visually monitoring plaque inflammation and the therapeutic effectiveness of statins.