Dear Doctors: I read that when you take statins, it raises blood glucose levels to a prediabetes or diabetes level. Does it happen even if your blood glucose is normal? How do statins work? My blood glucose is a bit high, and I'm worried it will go out of the normal range if I start to take them.
Dear Reader: Statins are a class of drug that can help lower unhealthful cholesterol levels in the blood. This, in turn, can lower the risk of developing certain types of heart disease.
Cholesterol, which is a fatty, waxlike substance, is found in cells throughout the body. It plays a key role in a number of vital functions, including maintaining the flexibility of cell membranes throughout the body and the brain and aiding in the synthesis of certain hormones and vitamins.
The liver produces the cholesterol that our bodies need. But factors such as diet, smoking, poor blood sugar control, being overweight or being sedentary can cause cholesterol levels to rise. Excess levels of blood cholesterol can lead to the formation of thick, hard deposits along the walls of the arteries, known as plaques. This can lead to blockages, and to a type of heart disease known as atherosclerosis, which increases the risk of heart attack and stroke. Plaque can also build up in the arteries that serve the heart, which is known as coronary artery disease.
When someone takes statins, it reduces the amount of low-density lipoprotein, or LDL, that the liver produces. That's the so-called “bad” cholesterol, which binds with other substances in the blood to form plaques. Statins work by blocking a liver enzyme involved in cholesterol formation. They can also aid in removing LDL from the blood and can play a role in stabilizing existing plaques, which can help prevent a rupture.
As with many medications, statins have potential side effects. These include muscle pain, headache, brain fog and fatigue. But recent research has also linked statins to an increased risk of developing insulin resistance. In some cases, this has led to prediabetes or to Type 2 diabetes. The reasons for this are not yet fully understood.
It is important to note that statins don't cause elevated blood sugar levels in everyone who takes them. An analysis of existing studies into the issue found this occurs in about 9% of people using the drug. Developing insulin resistance has been associated with moderate-to-high doses of the drug and is seen more often in people whose blood sugar levels are already high. This includes those who have been trending into the prediabetes range when they started taking the drug, or who already had been diagnosed with Type 2 diabetes.
If your doctor believes statins would be beneficial, be sure to discuss your concerns. If your medical profile and history put you at risk of developing insulin resistance while on the drug, they can help you take steps to protect yourself. These include dietary and lifestyle changes when starting the drugs, regular screenings for changes to blood sugar control and possibly choosing an alternative drug therapy for managing cholesterol levels.
(Send your questions to [email protected], or write: Ask the Doctors, c/o UCLA Health Sciences Media Relations, 10960 Wilshire Blvd., Suite 1955, Los Angeles, CA, 90024. Owing to the volume of mail, personal replies cannot be provided.)