Author + information
- J.L. Mehta, MD, PhD⁎ ()
- ↵⁎Division of Cardiovascular Medicine, University of Arkansas for Medical Sciences, 4301 West Markham Street, Mail Slot 532, Little Rock, Arkansas 72205-7199
Koh et al. (1), in a small number of patients given atorvastatin, showed that despite reductions in low-density lipoprotein cholesterol, atorvastatin treatment resulted in significant increases in fasting insulin and glycated hemoglobin levels consistent with insulin resistance in patients with hypercholesterolemia. These results are in agreement with our studies in 345,417 veteran patients (mean age 61 years; 94% men; 6% with diabetes), which showed that in patients without diabetes as well as those with diabetes, fasting blood sugar increased with the use of any statin (p < 0.0001) (2). After adjustment for age and the use of aspirin, beta-blockers, and angiotensin-converting enzyme inhibitors, the change in fasting blood sugar in patients without diabetes using statins was 7 mg/dl (vs. 5 mg/dl in patients not using statins; p < 0.0001), and for patients with diabetes using statins, it was 39 mg/dl (vs. 32 mg/dl in patients not using statins; p < 0.0001).
Sattar et al. (3) found a small but significant increase in diabetes in patients taking statins in an analysis of the results of several randomized controlled trials of statins.
The mechanisms by which statins may influence glucose metabolism are unclear. We suggested that statins may alter glycemic control by decreasing various metabolites, such as isoprenoid, farnesyl pyrophosphate, geranylgeranyl pyrophosphate, and ubiquinone, which enhance glucose uptake via glucose transporter type 4 in adipocytes and impair insulin release (2).
However, further work needs to be done to define the following: 1) Are the outcomes of patients who develop diabetes on statins different from those who do not? In other words, is the rise in fasting blood sugar just a laboratory curiosity or a real disease? 2) Do patients who develop diabetes need to be treated similarly as those who develop diabetes while not taking statins? 3) How soon after starting statins does altered glucose metabolism become evident? 4) Is the altered glucose metabolism related to the dose of statins? and 5) What is the precise mechanism of altered glucose metabolism?
- American College of Cardiology Foundation