Effects of High-dose StAtin Versus Low-dose Statin Plus Ezetimibe on Statin-Associated Muscle Symptoms & on Reaching Target LDL-C Levels Among Elderly Patients With Atherosclerotic Cardiovascular Disease

High-dose statins can reduce mortality and cardiovascular events in patients with established atherosclerotic cardiovascular disease (ASCVD). Therefore, US and European recommendations recommend that established ASCVD patients (coronary artery disease, cerebrovascular disease, peripheral vascular disease) use high-dose statins to lower LDL cholesterol levels by at least 50%. However, in actual practice, high-dose statins are relatively less used, and the reason is unclear, but it is believed to be due to concerns about the side effects of high-dose statins. Most of the side effects of statins are statin-associated muscle symptoms (SAMS), which are more common than the incidence in clinical studies, especially in frontline care. These muscle side effects are dose-dependent and are common at high doses, and the incidence is known to increase in the elderly over 70 years of age. However, the US recommendation recommends using high-dose statins to lower LDL cholesterol by 50% or more to prevent cardiovascular events even in ASCVD patients over 70 years of age.

Most early studies on lowering LDL cholesterol in ASCVD patients used high doses of statins. However, after introducing cholesterol absorption inhibitors ezetimibe and PCSK9 inhibitor, large-scale clinical studies have been conducted to lower LDL cholesterol using these drugs. In this study, as in the statin study, cardiovascular events were significantly reduced, and together with statins, it became a standard treatment for ASCVD patients. On the other hand, the clinical benefit shown in clinical studies using cholesterol-lowering agents so far depends entirely on how much LDL cholesterol is lowered and how long it is maintained in a low state, indicating that LDL cholesterol management is the core of arteriosclerosis treatment. In addition to high-dose statins, a combination of low-dose statins and ezetimibe can be cited as a method for lowering LDL cholesterol to more than 50%. In the latter case, it is expected that there will be an advantage of reducing muscle side effects by reaching the target LDL cholesterol level by using a low-dose statin. However, no studies compare the difference in muscle side effects between low-dose statins and ezetimibe combination drugs, which reduce LDL cholesterol to the same extent compared to high-dose statins, in elderly patients over 70 years of age with ASCVD. In this study, the association of low-dose rosuvastatin 5mg and ezetimibe combination (rosuvastatin 10/5mg) compared to high-dose rosuvastatin 20mg in elderly patients 70 years of age or older with established ASCVD. This study aims to compare and analyze the incidence of muscle symptoms (SAMS) and their effect on LDL cholesterol.