Differences in the atherogenic risk of patients treated by lipoprotein apheresis according to their lipid pattern

Abstract

In high-risk patients who are already on a maximal lipid-lowering therapy, a lipoprotein apheresis is an important therapeutic option in preventing further progress of vascular complications as it may decrease both LDL-cholesterol (LDL-C) and lipoprotein(a) (Lp(a)) levels. We looked at the occurrence of cardiovascular events before apheresis and during apheresis in three groups defined by their lipid patterns at the start of an apheresis treatment: Group 1 (LDL-C ≥ 3.4 mmol/l and Lp(a) ≤ 600 mg/l; n = 35), Group 2 (LDL-C ≤ 3.4 mmol/l and Lp(a) ≥ 600 mg/l n = 37) and Group 3 (LDL-C ≥ 3.4 mmol/l and Lp(a) ≥ 600 mg/l; n = 15). Group 2 shows a time period of about 10 years from the first event until the start of apheresis treatment (compared to 2-6 years in the other two groups). Before the start of apheresis treatment 2.1 events per patient had occurred in Group 1, 3.4 events per patient in Group 2 and 1.8 events per patient in Group 3. Under apheresis therapy just 0.9 events per patient occurred in Group 1, 0.5 in Group 2 and 0.5 in Group 3. When comparing the two years before the start of apheresis treatment with the first two years under apheresis we saw the following reduction rates of cardiovascular events: Group 1-54%; Group 2-83%; Group 3-83.5%. Our results show that the reduction of cardiovascular events due to lipoprotein apheresis is especially high in patients with elevated levels of Lp(a) compared to patients with elevated LDL-C only indicating that physicians should be more focused on the risk factor elevated Lp(a).