From the Guidelines
Atorvastatin can increase the risk of developing type 2 diabetes, particularly in individuals at high risk, and therefore, glucose status should be monitored regularly in these patients. This statin medication, commonly prescribed to lower cholesterol levels, may impair insulin secretion from pancreatic beta cells and reduce insulin sensitivity in muscle and liver tissues. Atorvastatin appears to interfere with glucose transporters, particularly GLUT4, which is essential for glucose uptake into cells. Additionally, the drug may decrease adiponectin levels, a hormone that normally improves insulin sensitivity. Some research suggests that statins like atorvastatin can also impair mitochondrial function in muscle cells, further contributing to insulin resistance.
Key Points to Consider
- The risk of developing diabetes while taking atorvastatin is dose-dependent, with higher doses carrying greater risk than lower doses 1.
- This risk is generally considered small compared to the cardiovascular benefits of statin therapy, especially in patients with established cardiovascular disease or multiple risk factors.
- Patients taking atorvastatin should have their blood glucose levels monitored periodically, particularly those with pre-existing risk factors for diabetes such as obesity, family history of diabetes, or elevated fasting glucose levels 1.
Recommendations for Clinical Practice
- It is not recommended that statins be discontinued due to the risk of developing type 2 diabetes 1.
- Glucose status should be monitored regularly in individuals at high risk of developing type 2 diabetes who are taking atorvastatin.
- Diabetes prevention approaches should be reinforced in these individuals to mitigate the risk of developing type 2 diabetes.
From the FDA Drug Label
Increases in HbA1c and Fasting Serum Glucose Levels Inform patients that increases in HbA1c and fasting serum glucose levels may occurwith atorvastatin calcium tablets.Encourage patients to optimize lifestyle measures, including regular exercise, maintaining a healthy body weight, and making healthy food choices [see Warnings and Precautions ( 5. 4)] .
Atorvastatin may increase the risk of developing type 2 diabetes due to its effect on increasing HbA1c and fasting serum glucose levels. The exact mechanism is not explicitly stated in the label, but it is recommended that patients optimize their lifestyle measures to minimize this risk. 2
From the Research
Mechanisms of Atorvastatin-Associated Diabetes Risk
- Atorvastatin, a high-intensity statin, is associated with a modest excess of type 2 diabetes mellitus, as seen in randomized trials and many observational studies 3.
- The proposed mechanisms for statin-associated diabetes risk include increased insulin resistance or impaired insulin secretion, with genetic polymorphisms and HMG CoA inhibition playing a role 3.
- Animal models have shown that HMG CoA inhibition has multiple downstream effects that may increase diabetes risk, including statin impairment of insulin signaling, decreased adipocyte differentiation, and decreased pancreatic β-cell insulin secretion 3.
Clinical Impact of Atorvastatin-Associated Diabetes
- The excess risk of diabetes appears to be confined to those who are already at risk for developing diabetes, with diabetes diagnosed only 2-4 months earlier in statin-treated patients 3.
- The clinical impact of statin-associated diabetes is likely unimportant, as the cardiovascular risk reduction benefit from statin far outweighs the potential for adverse effects in all but the very lowest risk individuals 3.
- Data have been accumulating on the risk of developing type 2 diabetes in patients receiving statins, and the potential adverse effects of these drugs on glycemic control in patients who already have type 2 diabetes 4.
Comparative Efficacy of Atorvastatin and Other Treatments
- Atorvastatin has been compared to other treatments, such as ezetimibe/simvastatin, in patients with type 2 diabetes and hypercholesterolemia, with varying results 5, 6, 7.
- These studies have shown that atorvastatin can be effective in reducing lipid parameters, but may not always be the most effective treatment option, and that the presence of predictive factors should be considered in planning lipid-altering therapy 5, 6, 7.