Is age an important factor for vascular response to statin therapy? A serial optical coherence tomography and intravascular ultrasound study
Age-related structural and functional changes in vessel wall may affect the time course of vascular response to statin therapy. In this study, we sought to compare the response of lipid-rich plaque to statin therapy in elderly versus younger patients using optical coherence tomography and intravascular ultrasound.Patients and methods
Sixty-nine patients who underwent serial optical coherence tomography and intravascular ultrasound at the time point of baseline, 6, and 12 months were divided into two groups according to median age: group A (age<57 years, n=35) and group B (age≥57 years, n=34). Patients were treated with intensive (atorvastatin 60 mg/day) or moderate (atorvastatin 20 mg/day or rosuvastatin 10 mg/day) statin therapy.Results
A continuous increase in fibrous-cap thickness (FCT) from baseline to 12 months was observed in both groups (P<0.001, <0.001, respectively). Intensive statin induced greater percent change in FCT at 12 months than moderate statin in group B (P=0.020), but not in group A (P=0.251). Mean lipid arc decreased significantly at 12 months in two groups (P<0.001, <0.001, respectively), and this response was delayed for 6 months (P=0.403) and began to decrease during the second 6 months (P<0.001) in group B. Normalized total atheroma volume decreased significantly in group A (P<0.001), but not in group B (P=0.349).Conclusion
Statin therapy could stabilize lipid-rich plaque irrespective of age, and intensive statin therapy was more effective than a moderate dose of statin in increasing FCT, particularly in older patients. A delayed response of lipid content and unfavorable change in normalized total atheroma volume to statin were observed in elderly patients.