Plasma high-density lipoproteins and ischemic heart disease: studies in a large kindred with familial...

Area of Science:

• Cardiovascular Genetics
• Lipid Metabolism
• Genetic Epidemiology

Background:

• Familial hypercholesterolemia (FH) is a genetic disorder characterized by high levels of low-density lipoprotein cholesterol (LDL-C).
• FH significantly elevates the risk of premature ischemic heart disease (IHD).
• Understanding the genetic and lipidemic factors contributing to IHD in FH is crucial for risk stratification and management.

Purpose of the Study:

• To investigate the expression of ischemic heart disease within a large kindred exhibiting familial hypercholesterolemia.
• To identify specific lipid profiles and genetic segregation patterns associated with IHD in FH.

Main Methods:

• Studied a large kindred with familial hypercholesterolemia.
• Analyzed lipid profiles, including total cholesterol, LDL-C, and high-density lipoprotein cholesterol (HDL-C).
• Examined segregation ratios for IHD and assessed the association between lipid levels and disease presence.

Main Results:

• Observed tendon xanthomas and multi-generational transmission consistent with FH.
• Found bimodality in total and LDL-C distributions.
• All but two IHD cases were in the upper quartile of total and LDL-C.
• Half of IHD cases were in the lower quartile of HDL-C.
• A high-to-low-density lipoprotein cholesterol ratio <= 0.20 was present in all IHD patients.
• Low HDL-C levels remained associated with IHD after adjusting for other lipids.

Conclusions:

• Both low high-density lipoprotein cholesterol (HDL-C) and high low-density lipoprotein cholesterol (LDL-C) are significant risk factors for ischemic heart disease in familial hypercholesterolemia.
• Lipid profiles, particularly HDL-C and LDL-C levels, are critical determinants of IHD development in FH kindreds.
• These findings highlight the importance of comprehensive lipid management in individuals with FH to mitigate cardiovascular risk.