Low hdl definition
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Definition and Implications of Low HDL Cholesterol
Extremely Low HDL Cholesterol: Definition and Causes
Extremely low high-density lipoprotein cholesterol (HDL-C) is defined as levels below 20 mg/dL. This condition can arise from various causes, including artifactual errors, primary monogenic disorders, or secondary factors. For instance, a case study highlighted a 55-year-old diabetic male with extremely low HDL-C, who also had apolipoprotein A1 deficiency and presented with acute myocardial infarction. This case underscores the diagnostic challenges posed by extremely low HDL-C levels, especially in the absence of severe hypertriglyceridemia.
Low HDL Cholesterol and Autoimmune Disease Risk
Low HDL cholesterol is also linked to an increased risk of autoimmune diseases. A large-scale study involving over 117,000 individuals from the Copenhagen General Population Study and the Copenhagen City Heart Study found that lower HDL-C levels were associated with a higher risk of developing autoimmune diseases. Specifically, individuals with HDL-C levels below 39 mg/dL had a significantly higher risk compared to those with levels above 77 mg/dL. This association remained consistent across various subgroups and conditions, suggesting a robust link between low HDL-C and autoimmune disease risk.
Conclusion
In summary, extremely low HDL cholesterol is defined as levels below 20 mg/dL and can result from multiple causes, including genetic and secondary factors. Additionally, low HDL cholesterol levels are associated with a higher risk of autoimmune diseases, highlighting the importance of maintaining adequate HDL-C levels for overall health. Understanding these associations can aid in better diagnosis and management of related health conditions.
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