Effect of PCSK9 inhibitors on remnant cholesterol and lipid residual risk: The LIPID-REAL registry

Background Monoclonal antibodies that inhibit the proprotein convertase subtilisin/kexin type 9 (PCSK9) reduce low-density lipoprotein cholesterol (LDLc) by 55%, regardless of baseline treatments. Nonetheless, the effect of other lipid parameters, such as cholesterol remnants or, the so-called lipid residual risk, is unknown. Methods Multicenter and retrospective registry of patients treated with PCSK9 inhibitors from 14 different hospitals in Spain. Before and on-treatment lipid parameters were recorded. Residual lipid risk was estimated by (1) cholesterol remnants, (2) triglycerides/HDLc ratio (TG/HDL), (3) total cholesterol/HDLc (TC/HDL) and (4) the triglycerides-to-glucose index (TGGi). Results Six hundred fifty-two patients were analysed, mean age of 60.2 (9.63) years, 24.69% women and mean LDLc before treatment 149.24 (49.86) mg/dl. Median time to second blood determination was 187.5 days. On-treatment LDLc was 67.46 (45.78) mg/dl, which represented a 55% reduction. Significant reductions were observed for TG/HDL ratio, cholesterol remnants, TC/HDL ratio and TGGi. As consequence, 34.61% patients had LDLc <55 mg/dl and cholesterol remnants <30 mg/dl; additionally, 31.95% had cholesterol remnants 55 mg/dl. Patients who had levels of cholesterol remnants >30 mg/dl before initiating the treatment with PCSK9 had higher reductions in cholesterol remnants, TG/HDL ratio, TC/HDL and TGGi. By contrast, no reduction differences were observed according to baseline LDLc (< or > the mean), age, gender or obesity. Conclusions This multicenter and retrospective registry of real-world patients treated with PCSK9 inhibitors demonstrates a positive effect on cholesterol remnants and lipid residual risk beyond LDLc reductions.