Comparison of the low-density lipoprotein cholesterol target value and the preventive effect of statins in elderly patients and younger patients

Objective To assess whether the low-density lipoprotein cholesterol (LDL-C) target value and preventive effect of statins are different between elderly and younger patients. Methods We investigated 304 patients with previous percutaneous coronary intervention who underwent coronary angiography from January 2007 to December 2016 for examination of recurrent ischemia beyond the early restenosis. Patients were classified into two groups: age ≥ 75 years (elderly group: n = 140) and n = 164). Relationships between the achieved LDL-C level, incidence of late coronary events, and the effectiveness of statins were evaluated. Results During follow-up, 179 patients underwent late coronary revascularization. Recurrent ischemia presenting as acute coronary syndrome (ACS) occurred in 83 cases. Kaplan-Meier curve analysis revealed that in the younger group, recurrent ACS was significantly lower in patients with LDL-C P = 0.035); however, there was no difference between these in the elderly group (P = 0.863). Instead, recurrent ACS was less frequent in patients with LDL-C ranging from 70 mg/dL to P = 0.005); moreover, only using statins was an independent predictor in the elderly group (HR: 0.375; P = 0.007). Conclusions Strict control of LDL-C to < 70 mg/dL was effective for reducing the incidence of recurrent ACS in younger patients. However, LDL-C < 100 mg/dL might be sufficient as the target value of LDL-C-lowering therapy for secondary prevention of ischemic events in Japanese elderly patients.