Link Between Statins and Developing Diabetes
Statins can raise blood sugar levels. However, certain statins may have more neutral effects. Find out which ones.
When statins were first introduced in 1987, numerous trials confirmed their efficacy in lowering LDL-cholesterol (bad cholesterol) and reducing the risk of heart disease.
Initially, these trials even indicated a decreased risk of new-onset diabetes. However, later and larger trials, such as JUPITER (Justification for the Use of Statins in Prevention: an Intervention Trial Evaluating Rosuvastatin), found a higher incidence of new-onset diabetes (3.0%) in the rosuvastatin group compared to the placebo group (2.4%).
This observation raised several important questions.
Are all statins associated with this increased risk of diabetes, or is it specific to certain ones? Is the risk dose-dependent, meaning does higher dosage increase the risk further? And ultimately, do the potential risks of statins outweigh their benefits?
Let's dive into these questions to gain a deeper understanding.
Do statins cause diabetes?
There has been some research showing that statins may lead to an increase in blood sugar levels. This effect varies depending on the type and dosage of statin used.
While all statins have been found to raise blood glucose levels to some extent, the risk of developing new-onset type 2 diabetes appears to be around 10% higher over five years for people on statin therapy.1
Does the risk increase with higher-strength statins?
Recent findings indicate that the risk of developing new-onset diabetes is higher with higher-intensity statins, such as atorvastatin (40–80mg) and rosuvastatin (10–20mg), compared to moderate or low-intensity statins.
For those who are taking moderate-intensity statins and need further reduction in LDL cholesterol, adding another medication like ezetimibe may be a viable option, particularly for those who are pre-diabetic. Ezetimibe is an affordable and generally well-tolerated add-on therapy to help reach cholesterol goals.
Do certain statins have a reduced risk for developing diabetes?
Yes, some statins may have a smaller impact on changes to blood sugar levels and the risk of developing diabetes compared to others.
Pitavastatin has been linked to a lower risk of developing diabetes. However, it's important to note that there is not enough data from large trials to fully understand its effects on heart health.
In a recent clinical study, researchers investigated the effects of moderate-intensity pitavastatin, rosuvastatin, and atorvastatin in patients who had recently experienced a heart attack.
The study found that moderate-intensity pitavastatin had a lower risk of causing new-onset diabetes compared to moderate-intensity atorvastatin or rosuvastatin.
This information could be helpful for individuals and their doctors when considering which statin might be the best choice for them, especially if they have concerns about diabetes risk.
Why do statins increase the risk of new-onset diabetes?
The exact reasons are not completely understood, but researchers have proposed several theories to explain this association.
Some argue that statins are not the cause. People with high cholesterol might already have other risk factors for diabetes, such as high blood pressure, being overweight, or insulin resistance. This group may have been at higher risk of developing diabetes even without taking statins.
Despite this, many experts agree that statins do increase the risk of new-onset diabetes to some extent, as shown in multiple clinical trials. The mechanism behind this is not entirely clear.
Statins work by blocking an enzyme in the liver called HMG-CoA reductase, which is involved in cholesterol production. Studies in animal models suggest that disruptions in this enzyme can lead to increased insulin resistance and diabetes.
In lab studies with cells and animal experiments, statins have also been found to affect the mevalonate pathway, which could result in impaired function of beta cells in the pancreas (cells that release insulin) and decreased insulin sensitivity.
Initially, it was believed that all statins shared this risk, but recent insights suggest that some statins like pravastatin and pitavastatin may have more neutral effects on blood sugar levels in patients with and without diabetes.
Based on these findings, it is thought that statins may increase the risk of new-onset diabetes by influencing insulin resistance or impairing insulin secretion in beta cells. Over time, these effects could make a person more susceptible to developing type 2 diabetes.
Although statin therapy is associated with a small increase in the risk of new-onset diabetes, the benefits of statins in preventing cardiovascular disease far outweigh the potential risk of slightly elevated blood sugar levels. If you are prescribed a statin, rest assured that your doctor has considered these factors and chosen the medication because of its overall positive impact on heart health.
What should you do if you are pre-diabetic and have high-cholesterol?
Everyone is different. Talk to your healthcare provider of the risk and benefits of statin therapy to decide the best course of treatment for you.
Optimizing lifestyle measures, including regular exercise, maintaining a healthy body weight, and making healthy food choices is a great first step to improving your health and lowering your cholesterol levels. For some, these changes will not be enough to get cholesterol levels down to normal levels.
While statins increase your risk of developing diabetes, the benefit of statins in reducing your risk of heart disease outweigh the risk of developing diabetes. Your healthcare provider will likely use a tool like a ASCVD Risk Calculator to determine the risk-benefit of statin therapy.
Together, you and your healthcare provider can develop a plan to get your cholesterol levels under control to lower your risk.
What should you do if you are diabetic and have high cholesterol?
The most recent Blood Cholesterol guidelines recommend that if you have type 2 diabetes and are between the ages of 40 to 75, you should be started on a moderate or high-intensity statin if your LDL-cholesterol levels are greater than 70mg/dL. This is because diabetes significantly increases your risk of heart disease, so any efforts that can be made to reduce your risk are recommended.
If you are already taking a statin, make sure to keep an eye on your hemoglobin A1c and blood glucose levels. Proper management of these levels is essential for your overall health and to avoid complications.
If you have any questions of concerns about statins or any other medications you are taking be sure to ask your healthcare provider, or give us a call for a free pharmacy consult.