Causes of Low Cholesterol in People with Kidney Disease
To determine the causes of low cholesterol, it’s good to know what cholesterol is. It’s a fatty substance that is produced by your body. Cholesterol is also present in some of the foods you eat. Too much cholesterol can build up and sometimes lead to a narrowing of the arteries, also known as hardening of the arteries, that restricts blood flow.
When the blood vessels of your heart become restricted, coronary heart disease develops. If your heart doesn’t get the blood and oxygen it needs, you could experience chest pain or even a heart attack.
In the general population, high cholesterol puts people at risk for cardiovascular disease. But for people with chronic kidney disease (CKD) and those on dialysis, the relationship between cholesterol level and heart disease is not as certain. In Trinidad & Tobago, approximately 500,000 people are undergoing dialysis, and nearly half of those patients will die of cardiovascular disease complications.
Yet some studies have shown that dialysis patients with higher cholesterol levels actually live a longer life than those with lower cholesterol levels. This is not to say that high cholesterol is good for CKD patients. Rather, the high cholesterol levels in some patients can suggest that they experience a lesser degree of two complications of kidney disease: malnutrition and inflammation.
Malnutrition and inflammation in patients with kidney disease
Malnutrition is common among patients with end stage renal disease (ESRD) and can affect up to 75 percent of dialysis patients.
It is believed that toxins not removed by dialysis can interfere with a patient’s sense of taste and smell. Without a normal sense of smell, food can lose its appeal, and dialysis patients become uninterested in eating. This leads to severe malnutrition and is one of the reasons why a patient’s cholesterol declines to a low level.
As an individual’s kidney function declines, he or she typically eats less and less food. Elderly patients in particular may develop cachexia, a disease that results in loss of weight and muscle mass.
If food has lost its appeal for you, talk to your renal dietitian about the types of food you should eat and what can be done to enhance food’s flavor, such as the addition of herbs and spices.
Cholesterol levels also tend to be lower if a patient is intentionally placed on a low-calorie diet or was prescribed a cholesterol-lowering medication.
Inflammation is another common complication of CKD, and some research has linked inflammation and low cholesterol levels. Although low cholesterol levels in people with kidney disease may be an indicator of other health conditions, most experts agree that, at this time, it is not entirely clear what the link is.
Malnutrition and inflammation in patients with CKD can complicate blood cholesterol test results. Your healthcare team will want to thoroughly examine all of the possible causes of your low cholesterol reading.
What other items are used to measure risk for heart disease?
Aside from high LDL cholesterol levels, the risk for heart disease increases with the following risk factors:
- cigarette smoking
- high blood glucose
- low HDL cholesterol
- age (men > 45 years old; women > 55 years old)
- high blood pressure or on antihypertensive medications
- diabetes mellitus
- family history of early heart disease
- other forms of vessel narrowing diseases.
People with CKD may have some added risk factors that lead to heart disease:
- large calcium intake from diet or medication
- high blood phosphorus levels
- high parathyroid hormone levels
- high homocysteine levels
- whole body inflammation.
People who are physically inactive or who eat foods that are high in saturated fat and cholesterol are also at risk for developing heart disease.
What can I do to decrease my risk for heart disease?
- Increase physical activity to 30 minutes every day at a moderate level. This will help:
- raise HDL cholesterol
- lower LDL cholesterol in some people
- lower blood pressure
- improve diabetic control
- improve heart function.
- Obtain and maintain a healthy weight
- Talk to your doctor and dietitian
- Do not smoke.
- Do not drink alcohol excessively. (Limit alcohol to 1 drink a day with physician approval.)
- Choose foods that are low in saturated fat and cholesterol. See “Tips to reduce fat and cholesterol in your diet.”
- Decrease use of trans fatty acids since they can raise LDL cholesterol.
- Use plant stanols and sterols found in regular or “light” specially formulated margarine-like spreads. Increase soluble fiber. (Fruits and vegetables and grains are good sources of fiber.)
- Talk with your dietitian for assistance with safely and gradually increasing fiber in your diet.
Treatment of Other Risk Factors:
- Control hypertension and diabetes.
- Treatment for these diseases can include medications, diet changes and increased physical activity.
- Your doctor and dietitian can help you with lifestyle changes to best treat these diseases.
What about medications to help lower my risk for heart disease?
Medications are available for lowering LDL cholesterol and triglycerides, but heart disease medications work the best when diet and life style changes have already been made.
Who can I talk to about specific questions I have to reduce my risk for heart disease?
- Your doctor can talk to you about how best to treat your risk for heart disease.
- A pharmacist can answer questions you might have about any medications the doctor has prescribed for you.
A dietitian can help you in making healthy food changes to your diet.
Tips to Reduce Fat and Cholesterol in Your Diet
- Choose lean meats, poultry and fish. The loin and round cuts of meat tend to be leaner than rib cuts and organ meats.
- Trim all visible fat from meat and remove skin from poultry.
- Steam, broil, roast or bake meat, poultry and fish. Place the food on a rack to allow the fat to drain away from the food. Do not fry foods.
- Choose fresh fruits and vegetables. Steam, boil, bake or microwave vegetables. Do not fry foods.
- Use nonstick pans or vegetable sprays for sautéing.
- Use herbs and spices to season foods instead of sauces, butter or margarine.
- Try wine, lemon juice, or flavored vinegar to give flavor with limited fat and calories.
- Use jelly, jam, honey or syrup instead of butter or margarine on toast, waffles, pancakes or muffins.
- Use fat free or reduced fat versions of high-fat foods. For example, use fat-free sour cream in place of regular sour cream or use 1% or skim milk in allowed amounts.
- Limit hydrogenated and partially hydrogenated fats. These can be found in some margarines, peanut butters, packaged baked goods and snacks, and fried foods. Try baked crackers instead of fried crackers. Buy grilled or baked items when eating out.
- Use two grams of plant stanols or sterols per day. These are sold as specially formulated margarine-like spreads. Your dietitian can assist you with finding these products.
- Limit products made with coconut, palm kernel, palm oil, lard, shortening, bacon fat and cocoa butter.
- Use canola or olive oils instead of shortening, butter or other oils when cooking. These monounsaturated fats will not lower your HDL level.
- Try sherbet or ice milk instead of ice cream.
- Read food labels on the foods you buy. Do not be misled by foods that are cholesterol free but contain large amounts of saturated fat that your body will turn into cholesterol.
For most people, a low cholesterol reading indicates less risk of cardiovascular disease. For a patient with kidney disease, the cause of a low cholesterol reading can be an indicator of underlying kidney disease complications, such as malnutrition and inflammation. Your doctor will examine all possible causes of your low cholesterol level so the right treatment is prescribed, and you can live a better quality of life with kidney disease.