Feline Hyperlipidemia: High Cholesterol & Triglycerides Guide

Feline Hyperlipidemia: High Cholesterol & Triglycerides Guide

고양이의 고지혈증: 고콜레스테롤 및 고중성지방혈증 가이드

Intro: what is hyperlipidemia?

Hyperlipidemia in cats is a state where blood lipids — triglycerides or cholesterol — are abnormally elevated.

ℹ️
The term hypercholesterolemia is common, but in veterinary medicine "hyperlipidemia," which also includes elevated triglycerides, is the broader term with richer research data.

🏠 Main causes (primary vs secondary)

Feline hyperlipidemia is most often secondary, caused by another underlying disease.

CategoryMain causes & cautions
Physiological Temporary rise after a high-fat meal (2-10 hours postprandial)
Dietary Continuous feeding of an excessively high-fat diet
Hormonal disease
  • Diabetes mellitus: increased VLDL production.
  • Hypothyroidism: reduced cholesterol metabolism. (※ Rare in cats; if caused by iodine deficiency, it can sometimes resolve with iodine supplementation.)
  • Hyperadrenocorticism (Cushing): increased lipid mobilization.
  • Acromegaly
Organ disease
  • Pancreatitis: reduced LPL enzyme activity.
  • Nephrotic syndrome: increased hepatic cholesterol synthesis due to degenerative kidney disease.
  • Liver/biliary disease: impaired cholesterol excretion during cholestasis.
Drugs & genetics Corticosteroid administration; genetic lipid-degrading enzyme deficiency

🔬 The role of lipoproteins

Lipids do not dissolve in water, so they travel through the blood loaded onto "boats" called lipoproteins. Cats have unique lipid-metabolism traits that differ from humans.

  • Chylomicrons & VLDL: the main carriers of triglycerides.
  • LDL (bad cholesterol): supplies cholesterol to tissues, but cats have relatively low levels.
  • HDL (good cholesterol): the main cholesterol carrier in cats. It collects surplus cholesterol and sends it to the liver.
💡
Why are cats resistant to atherosclerosis?
Unlike humans, cats use HDL as the main carrier and lack cholesteryl ester transfer protein (CETP), so little converts to LDL. But once levels exceed 650 mg/dL, even cats enter the atherosclerosis risk group.

❤️ A close relationship with heart disease

According to Fox et al. (1993, AJVR), cats with heart disease show specific lipid patterns.

Heart diseaseLipid & nutrient changes
Dilated cardiomyopathy (DCM) Highest triglycerides (2× healthy cats), cholesterol down 36%, taurine plummeting to 38% of normal.
Hypertrophic cardiomyopathy (HCM) Triglycerides up 54%, retinol (vitamin A) up 15%.
Hyperthyroidism Cholesterol down more than 30%, taurine slightly reduced.

⚠️ Cautions when supplementing B vitamins

When over-supplementing B vitamins (e.g., for kidney disease), even though they are water-soluble, high doses (10-30× the recommended amount) can be dangerous.

  • Niacin (B3): high doses can cause liver toxicity, which may reduce the liver's ability to excrete cholesterol and thus raise levels.
  • Pyridoxine (B6): supplemental B6 can cause sensory neuropathy, and has been reported to stimulate hepatic glycogen mobilization, potentially affecting blood-glucose and lipid levels.

📍 Summary & conclusion

  • Feline hyperlipidemia is usually secondary, so first look for underlying causes like diabetes, pancreatitis, or kidney disease.
  • Elevated triglycerides can be a warning sign of heart disease (HCM, DCM).
  • In cats with hyperthyroidism, it is actually normal for cholesterol to come back low.
  • When cholesterol is 650 mg/dL or higher, active lipid management is needed.

References

  • Fox PR, et al. Comparison of taurine, alpha-tocopherol, retinol, selenium, and total triglycerides and cholesterol concentrations in cats with cardiac disease and in healthy cats. AJVR. 1993 Apr.
  • Berent AC, et al. Liver Function in Cats with Hyperthyroidism Before and After I131 Therapy. JVIM. 2007.
  • Rand J. Problem-based Feline Medicine. Elsevier Health Sciences, 2006.