High Cholesterol in Dogs

Hyperlipidemia refers to the elevation in blood lipids (fats) and is fairly common in dogs. After a dog eats a meal, triglycerides and cholesterol levels rise in the blood and then come back down to normal levels again within 3-10 hours. However, in hyperlipidemia, fat levels remain high for over 12 hours. Several metabolic diseases demonstrate hyperlipidemia, including diabetes, hypothyroidism and Cushing’s syndrome. Some dog breeds are genetically predisposed to hyperlipidemia. Hyperlipidemia does not normally lead to heart disease, but can decrease lifespan and cause obesity, neurologic and metabolic issues. Hyperlipidemia is a condition in which the amount of fats (also called lipids) in the blood are elevated. The most important lipids are cholesterol and triglyceride. Hyperlipidemia is a common and under-diagnosed dog health problem that can negatively impact health and longevity.

Symptoms may be absent or may correlate with the underlying cause of the hyperlipidemia. Symptoms of hyperlipidemia can include:

• Decreased appetite
• Vomiting
• Diarrhea
• Abdominal pain
• Bloated abdomen
• Cloudy eyes
• Fatty deposits under the skin
• Hair loss
• Itching
• Seizures

Possible causes of hyperlipidemia include:

• High-fat diets – dietary intake of fats is a common cause of hyperlipidemia
• Obesity – high body fat and associated issues
• Steroid medications – progesterone and corticosteroids
• Diabetes - can cause increased hormone-sensitive lipase activity
• Hypothyroidism - can cause increased hormone-sensitive lipase activity and increased serum LDL
• Cushing’s syndrome - can cause increased hormone-sensitive lipase activity
• Pancreatitis – inflammation of the pancreas
• Cholestasis – excretion in the bile is the major way the body removes excess fats
• Nephrotic syndrome – kidney disease can cause increased hormone-sensitive lipase activity
• Pregnancy – hyperlipidemia may be seen temporarily during pregnancy
• Genetic predisposition – Miniature schnauzers and Beagles tend to be genetically predisposed to hyperlipidemia.

Types

Hyperlipidemia can be physiological or pathological

• Physiological – high lipid levels due to having recently eaten a meal (normal increase)
• Pathological – The body is either unable to clear fats from the blood, is synthesizing lipoproteins, or is stabilizing lipoproteins so they cannot be broken down. (abnormal increase)

Hyperlipidemia can be primary or secondary

• Primary – genetic or of unknown origin
• Secondary – caused by an underlying disease

Hyperlipidemia can involve one or more of the following:

• Elevated blood triglycerides
• Elevated blood cholesterol
• Elevated blood chylomicrons (protein-coated triglycerides)

You may want to eliminate all table scraps and gradually switch your pet over to a low-fat, high-fiber dog food as diets high in fat are a common cause of hyperlipidemia. However, results from diet changes can take 6-8 weeks. If you are seeing symptoms associated with hyperlipidemia in your pet, you will need to visit the veterinarian to determine the underlying cause. A full history of your pet and a thorough physical exam will determine what diagnostic tests may be necessary.

Laboratory tests used to help diagnose hyperlipidemia and identify any underlying causes can include a complete blood cell count to detect blood abnormalities, biochemistry to examine kidney and liver function, urinalysis to examine urinary tract function, a thyroid test to measure thyroid hormone production, a CPL (canine pancreatic lipase) assay to measure lipase levels and detect possible pancreatitis, lipid tests to examine levels of various lipoproteins to aid in locating where the metabolic issue lies and a cortisol test to measure adrenal gland function. The pet must not eat any food or treats 12 hours prior to the cortisol test. Morning appointments are best.

Dietary Change

A common contributor to hyperlipidemia is a diet high in fat. Table scraps can be the biggest problem, however many commercial dog foods can be too high in fat for some pets as well. A low-fat, high-fiber diet can help reduce blood lipids. Proper portion sizes and daily exercise can prevent obesity, also a contributing factor to hyperlipidemia. Homemade diets are not recommended as they often lack in daily vitamin and mineral requirements.

Dietary changes must be made gradually to avoid upsetting the gastrointestinal tract. Unless your veterinarian instructs otherwise, once a new food is purchased, mix half of the new food with half of the old food and feed this mixture for 7 days. Thereafter, you can safely feed the new food only.

Lipid-Lowering Medications

Medications are available that can lower triglyceride and cholesterol levels in the blood. Human statin drugs are not safe for use in animals (Gemfibrizol)

Secondary Condition Medications

Treatment of the underlying cause of hyperlipidemia will often resolve high circulating lipid levels. Diabetes’s, Cushing’s syndrome, and hypothyroidism can all be addressed with medication.

Your pet will need to be on a blood monitoring schedule depending on the diagnosed cause of the hyperlipidemia to ensure that he is responding to treatment. Follow up exams may be weekly or monthly until drugs are adjusted to appropriate levels. After medication levels are established, blood tests may be conducted every 6-12 months to monitor.

Be sure that dietary changes are explained to family and friends clearly to keep the pet free from exposure to table scraps or disposed food. Instructions for medical treatment and dietary treatment must be followed for them to be effective. Discontinuation of treatment can be dangerous. Acute pancreatitis (potentially fatal) can result from a pet eating fatty foods after being on a low-fat diet for some time.

Treatments are normally successful in resolving high-lipid blood levels and are often required to be continued through the life of the pet.

Once your dog has high cholesterol the easiest way to manage it is to change their diet. A bag of low fat, high fiber dog food can cost between $18 and $45 per bag. Exercise is a great way to help manage your dog’s condition, especially if the cause of the high cholesterol is weight related. It also doesn’t cost a thing, except a little of your time. Your veterinarian may prescribe Gemfibrozil (to lower the lipid count) which can cost between $10 and $25. The high cholesterol is usually the result of an underlying cause such as diabetes, Cushing’s disease or hypothyroidism. Treating diabetes can cost around $350 every two months (the cost of the new food, insulin, needles, and testing strips). Treating Cushing’s disease can vary greatly in cost. However, Lysodren is a popular treatment option and can cost about $75 per month. Hypothyroidism can get pretty pricey (around $480) once you factor in the cost of blood work, a consultation and medication. These options can cost anywhere between $75 and $385 and up. However, the overall cost of treating high cholesterol will depend greatly on the initial cause.