Diabetes and high cholesterol

Summary

High cholesterol and diabetes often go together. Insulin resistance, which often precedes type 2 diabetes, changes the way the body handles fats. The result is diabetic dyslipidemia: high LDL (“bad cholesterol”), low HDL and high triglycerides. The combination raises the risk of early atherosclerosis, heart attack and stroke.

Like any high cholesterol, this causes no symptoms: it is detected only with a blood test.

The typical pattern in diabetes

• High triglycerides — often after refined carbohydrates, sweet drinks and alcohol
• Low HDL — lowered by overweight, lack of exercise and smoking
• LDL in “acceptable” ranges, but with small, dense particles that are deposited in arteries more easily. For this reason, in diabetes non-HDL cholesterol or apolipoprotein B are also requested, when indicated.

Poorly controlled glucose makes this pattern worse; improving blood sugar often lowers triglycerides.

What your LDL should be

The target depends on your overall risk and is set by the doctor:

• recent, short-duration diabetes with no other risk factors — a more relaxed target
• diabetes for more than 10 years or with other risk factors — a lower target
• diabetes with organ damage (kidneys, eyes) or with known cardiovascular disease — a very low target (usually below 55 mg/dL)

Triglycerides below 150 mg/dL are desirable. Very high values (above 500 mg/dL) require special evaluation because of the risk of pancreatitis.

Treatment

Lifestyle — the foundation for everyone:

• less saturated fat (fatty meat, butter, industrial sweets) and no trans fats
• more vegetables, legumes, whole grains, fish, olive oil, nuts
• little simple sugar and few sweet drinks, little alcohol — these help triglycerides in particular
• weight loss and at least 150 minutes of physical activity a week
• stopping smoking

Medicines:

• Statins — the basic treatment; shown to reduce heart attacks and deaths in diabetes as well
• Ezetimibe — added when a statin is not enough
• Other medicines for very high risk
• For very high triglycerides, the doctor may add other medicines, after checking for secondary causes

What else raises cholesterol

Before attributing it only to “an effect of diabetes”, the doctor looks for:

• hypothyroidism (an underactive thyroid)
• kidney and liver diseases, including hepatic steatosis
• medicines that raise it (some diuretics, corticosteroids)
• familial hypercholesterolemia, when LDL is very high (above 190 mg/dL) or there is a family history of early heart attack

Regular checks

• The lipid profile usually does not require fasting; it may be requested when triglycerides are high.
• It is repeated 6–8 weeks after starting or changing treatment, then usually once a year.
• Tell the doctor about new muscle pain on a statin or if you are planning a pregnancy.
• Do not stop the statin on your own because of a single test or fear of side effects — talk to your doctor.