Comparison of Clinical Characterization and Therapeutic Strategies between Homozygous Familial Hypercholesterolemia...

Homozygous Familial hypercholesterolemia (HoFH) is a rare genetic disease characterized by very high levels of low-density lipoprotein cholesterol (LDL-C). Owing to LDL receptor activity being completely or nearly all lost in HoFH, LDL-C levels greatly exceed normal levels, and are even higher than in heterozygous (HeFH), which can cause fatal cardiovascular disease even in infancy. The current study updates differences in clinical characterization, therapeutic strategies and cardiovascular outcomes between HoFH and HeFH.

A total of 157 patients who were genetically or clinically diagnosed with FH (HoFH: 15, HeFH: 142) were retrospectively analyzed. Clinical characteristics, lipid profiles and atherosclerotic prognosis were evaluated between HoFH and HeFH patients.

Age and sex were similar between the two groups. Untreated LDL-C in HoFH was about double that in HeFH (498.4±164.3 vs. 232.0±60.5 mg/dL, p＜0.001), while on-treatment LDL-C with lipid lowering therapies did not differ significantly (83.8±59.1 vs. 127.1±59.6 mg/dL, p = 0.15). There was wide diversity in lipid lowering therapies between the two groups and a significantly higher prevalence of coronary artery and valvular disease in HoFH. Consequently, HoFH patients were more likely to receive percutaneous and surgical interventions at a younger age compared to HeFH patients.

The findings of this observational study show the clinical relevance of FH. Although both HeFH and HoFH are inherited disorders of lipoprotein metabolism, HoFH should be treated with a different, stricter therapeutic strategy to prevent premature ASCVD.