For years, the guidelines have been crystal clear. According to the American Heart Association, everyone with type 2 diabetes should be taking moderate-intensity statins. As far as we can tell, there are no exceptions to these rules. What may not be mentioned is the possibility that statins themselves may cause type 2 diabetes. Years ago, when we answered the questions you will see below, that was no more than a strong suspicion. Now we have data that shows statins increase the risk for diabetes. However, rosuvastatin is more likely to do so than atorvastatin. What is the evidence?
There Are Differences Amongst Statins:
When people have coronary artery disease, doctors usually prescribe statins to lower the patients’ likelihood of experiencing heart attacks, strokes or early death. But which statin works best? A new study called LODESTAR was designed to find out (BMJ, Oct. 18, 2023).
The Korean investigators compared atorvastatin (Lipitor) with rosuvastatin (Crestor) in a randomized trial comprising 4400 people with coronary artery disease. After three years, there was no difference between the two groups with respect to their chances of having a heart attack or stroke. There was, however, a difference with respect to side effects. Rosuvastatin, which lowered LDL cholesterol more than atorvastatin, also resulted in a higher risk of type 2 diabetes and cataracts.
This fact creates an interesting conflict. If statins can trigger diabetes or make it worse, should people keep taking their statin? This reader had his HbA1c go up dramatically after he was switched to atorvastatin.
Can Atorvastatin Raise HbA1C?
Q. Four months ago my HbA1c was 6.9 and glucose 115. I was taking 20 mg simvastatin.
Then my doctor switched me to 40 mg atorvastatin. My HbA1c went to 8.4 and glucose to 120. I have not changed my diet. I am very concerned about this noticeable change in my numbers. How can I control my blood glucose?
A. You have a reason to be concerned. Doctors diagnose type 2 diabetes when fasting blood glucose reaches 126. You are close, but below that cutoff.
Far more alarming, however, is your HbA1c. This blood test indicates blood sugar over several weeks. Anything over 6.5 suggests that blood sugar is out of control.
A study in JAMA Internal Medicine (Oct. 4, 2021) reveals that statin-type cholesterol-lowering drugs can interfere with blood glucose control. If your doctor is clear that a statin is essential, you will need to make some changes in both diet and exercise. Even with that, you may need medication to manage your blood sugar.
You can learn more about drugs that raise glucose, diets that can lower it and medicines to control it in our eGuide to Preventing and Treating Diabetes. This online resource can be found under the Health eGuides tab.
Doctor Contradicts Idea that Statins Increase the Risk for Diabetes:
Q. I have been taking a statin to control cholesterol for nearly 20 years. Over this time, my fasting blood sugar and HbA1c have risen steadily.
My A1c just hit 7.0 so I am now officially a type 2 diabetic. When I asked the doctor about the connection between statins and diabetes, he said these reports are based on small populations and are not credible. Is that correct?
Science: Statins Increase the Risk for Diabetes!
A. Actually, your physician has not kept up with the medical literature. One of the trials pointing to a link was called JUPITER. This seminal study was published quite a long time ago. In it, 17,802 older individuals volunteered to take rosuvastatin or placebo (New England Journal of Medicine, Nov. 20, 2008). There was a 26 percent higher chance of diabetes among those taking rosuvastatin.
90,000 Patients!
A meta-analysis of 13 clinical trials involving over 90,000 patients confirmed long ago that statins increase the risk of diabetes (Lancet, Feb. 27, 2010)
The authors downplayed its importance, though:
“Statin therapy is associated with a slightly increased risk of development of diabetes, but the risk is low both in absolute terms and when compared with the reduction in coronary events.”
From 2000 thru 2013:
Another review of the medical literature between 2000 and 2013 acknowledged the link between statins and diabetes (The Consultant Pharmacist, Vol. 29, # 5, 2014).
The authors concluded:
“Review of current, available clinical data suggest a possible association between statin use and incident diabetes in patients with underlying diabetes risk factors. Although study data may be insufficient to change the current practice paradigm, clinicians should vigilantly monitor for incident diabetes in patients on statins. Patients with a low risk of CV disease and high risk of diabetes should reconsider statin use and focus on lifestyle management.”
Risk Going Up:
A comprehensive analysis of this question in the journal Postgraduate Medicine (May, 2017) put some numbers around the risk:
“Several meta-analyses of randomized, controlled trials with statins and population-based studies of subjects taking statins have shown different incidence of NODM [new onset diabetes mellitus] ranging from 28% in the JUPITER study to 43% in the UK clinical practice cohort.”
Higher Still:
A more recent review published in Cardiorenal Medicine (April, 2018) puts the risk at 61%. The authors point out that health professionals originally thought statins might lower the risk of diabetes.
That has now changed:
“The recent literature, however, has suggested a relationship between statins and hyperglycemia to the extent of causing new-onset diabetes, thereby questioning the medication’s safety. The mechanism is not yet fully understood, but effects of hyperglycemia and rising HbA1c with statin use in both those with and those without diabetes have been recorded.”
“The results of this meta-analysis show that individuals on statins have an increased risk of developing NODM [new onset diabetes mellitus] compared to individuals who did not receive statins, which is in agreement with findings from a previous meta-analysis.”
Statins Increase the Risk for Diabetes Two Fold:
Finally, data published in Diabetes Metabolism Research and Reviews (May 24, 2019) reported that statin takers were more than twice as likely to develop type 2 diabetes compared to people not taking statins. This study involved over 7,000 patients.
So What if Statins Increase the Risk for Diabetes?
Most of the analyses we have cited acknowledge 1) that statins can trigger type 2 diabetes in some proportion of patients and then conclude 2) don’t worry, be happy. Researchers are quick to write that the benefits of statins far outweigh the risks of diabetes.
Readers Respond:
Geetha describes her transition to type 2 diabetes:
“I had no problems with blood sugar at all until I started taking rosuvastatin. At first this statin seemed to cause body aches and pains. I also had stomach discomfort. I stopped taking rosuvastatin and felt much better. But my doctor said because of my borderline cholesterol and high triglycerides, I had to take statins.
“Now, after a year of taking statins, my cholesterol levels are completely normal but I have diabetes. My blood glucose is 216. I have body aches and extreme fatigue along with leg cramps, thirst and frequent trips to the bathroom at night, all of which make me unable to sleep well at night. During the day I tire easily and suffer from extreme fatigue after the mildest of activities.”
Betty Ann adds this:
“I developed diabetes after taking atorvastatin. I am just now learning about the connection between the two. I have been told it’s my weight, it’s my diet, it’s hereditary, but NEVER has anyone suggested statins might be involved in causing diabetes.”
So, Statins Increase the Risk for Diabetes. What Now?
I think the doctor who rejected the idea of a statin-diabetes connection has not been keeping up with the research. Other health professionals are not happy with this result either. Read more at this link:
Do Statins Cause Diabetes? Many MDs Wish It Weren’t So!
Share your own story in the comment section. Some people will have to take statins despite the increased risk of diabetes. That said, people should be warned about this potential adverse reaction. And check out our eGuide to Preventing & Treating Diabetes. You can find it in the Health eGuides section of the website.
