Image from netdoctor.com
Millions of Americans suffer from high cholesterol and/or diabetes. High cholesterol and lipids lead to arteriosclerosis, which could cause heart attacks and stroke. High blood sugars in those suffering from diabetes increase arteriosclerosis as well, catapulting the risk of heart disease if one suffers from both conditions.
Statins, [such as simvastatin (Zocor), atorvastatin (Lipitor)] have been found to significantly lower LDL, or “bad cholesterol”. They gained huge popularity in the 90’s and 00’s and at one time were suggested to be used in diabetics without high cholesterol due to their cardio-protective nature.
Unfortunately studies began to suggest that statin medications may increase one’s risk of diabetes.
This week a study from Australia found an increase risk in diabetes in older women who took statins.
Now, many individuals with high cholesterol eventually develop diabetes, either through their eating habits, or the body’s inability to control rising blood levels of each. Sometimes high cholesterol precedes diabetes by a decade or more.
This study, however, looked at 8300 women born between 1921-1926 enrolled in the Australian Longitudinal Study on Women’s Health. They were free of diabetes in 2003 (averaging approximately 80 years old) and were followed for 10 years. Half of these women filled prescriptions for statins and of these 5% started filling medications for new onset diabetes. According to Medical News Today: Statistical analysis revealed that statin exposure was linked to a 33 percent higher risk of developing diabetes. The risk increased with dose of statin – up to 51 percent for the highest dose.
Dr. Mark Jones of the University of Queensland (UQ) in Brisbane, Australia said, “What is most concerning was we found a ‘dose effect’ where the risk of diabetes increased as the dosage of statins increased. Over the ten years of the study most of the women progressed to higher doses of statins. Those elderly women taking statins should be carefully and regularly monitored for increased blood glucose.”
Do statins cause diabetes?
This has yet to be proven definitively. One theory suggests statins interfere with the pancreas’ release of insulin, thereby causing sugar levels to rise. Another theory surrounds the statin’s ability to increase insulin resistance. Another study in 2015 found statins to increase calcium buildup in the arteries, but did not suggest a relationship to diabetes.
Many individuals who develop Type II Diabetes have evidence of high cholesterol years if not decades before. If a patient did not take a statin, would he have gone on to develop diabetes anyway? Or was the patient for years in a prediabetes state that caused the high lipids and then the overt diabetes years later?
Obviously the suggestion that statin medications may cause diabetes needs to be seriously considered and researched as the former significantly lowers cholesterol and heart attack risk but the latter could increase risk as well.
How do statins work?
Statins are HMG-CoA reductase inhibitors, meaning they inhibit the active part of the enzyme, HMG-CoA reductase. HMG-CoA reductase is involved in the metabolic pathway that produces cholesterol. Inhibiting this enzyme decreases cholesterol production.
A second effect of statins occurs when the liver senses less cholesterol being made. The organ increases its LDL receptors to catch more circulating LDL (bad cholesterol) in the blood, therefore reducing the chance for the bad cholesterol to deposit along arteries.
What is the purpose of cholesterol?
Cholesterol is essential in a variety of body processes. The waxy, fat-like substance is used to create the structure of the cell, make hormones such as estrogen, testosterone and cortisone, synthesize Vitamin D for bone health and create neurotransmitters, to name a few.
LDL vs. HDL
Both are created by the liver. LDL (low-density lipoprotein) delivers cholesterol to the cells to assist in the aforementioned biochemical processes.
High-density lipoprotein (HDL) provides the reverse transport of the cholesterol back to the liver so it could be degraded.
So higher levels of LDL (caused by diet or liver production) increase cholesterol in the blood which could result in plaquing, whereas higher levels of HDL, reduce circulating blood cholesterol, and therefore risk of heart disease.
Who needs statins?
Cholesterol can be high when one eats foods high in cholesterol. However, many produce excess amounts of cholesterol despite their dietary intake. Based on one’s risk for heart disease, the medical provider may need to prescribe a statin in order to decrease one’s liver from producing more of it or to decrease circulating blood levels of the harmful, waxy substance.
According to the American Heart Association and American College of Cardiology, statin therapy is recommended for the following groups:
- People without cardiovascular disease who are 40 to 75 years old and have a 7.5 percent or higher risk for having a heart attack or stroke within 10 years.
- People with a history of a cardiovascular event (heart attack, stroke, stable or unstable angina, peripheral artery disease, transient ischemic attack, or coronary or other arterial revascularization).
- People 21 and older who have a very high level of bad cholesterol (190 mg/dL or higher).
- People with Type 1 or Type 2 diabetes who are 40 to 75 years old.
Where should cholesterol levels be?
For most Americans:
Total cholesterol should be below 200 mg/dl,
LDL below 130 mg/dl, ideally below 100 mg/dl
HDL above 50 mg/dl , ideally 60 mg/dl
Triglyercides (fats) below 200 mg/dl , 150 mg/dl ideally