Prognostic impact of cascade screening for familial hypercholesterolemia on cardiovascular events

Abstract

Background: Familial hypercholesterolemia (FH) is an autosomal dominant disorder mainly caused by mutations in the low-density lipoprotein (LDL) receptor or associated genes, resulting in elevated serum cholesterol levels and an increased risk of premature atherosclerotic cardiovascular disease (ASCVD).

Objective: We aimed to evaluate the prognostic impact of cascade screening for FH.

Methods: We retrospectively investigated the health records of 1050 patients with clinically diagnosed FH, including probands and their relatives who were cascade-screened, who were referred to our institute. We used Cox models that were adjusted for established ASCVD risk factors to assess the association between cascade screening and major adverse cardiac events (MACE). The median period of follow-up evaluating MACE was 12.3 years (interquartile ranges [IQR] = 9.1-17.5 years), and MACE included death associated with ASCVD, or acute coronary syndrome.

Results: During the observation period, 113 participants experienced MACE. The mean age of patients identified through cascade screening was 18-years younger than that of the probands (38.7 yr vs. 57.0 yr, P < 0.0001), with a lower proportion of ASCVD risk factors. Interestingly, patients identified through cascade screening under milder lipid-lowering therapies were at reduced risk for MACE (hazard ratio [HR] = 0.67; 95%CI = 0.44 to 0.90; P = 0.0044) when compared with the probands, even after adjusting for those known risk factors, including age, and prior ASCVD.

Conclusions: The identification of patients with FH via cascade screening appeared to result in better prognosis.

Keywords: Cascade screening; Familial hypercholesterolemia; LDLR; PCSK9.