Rectifying 2013 ACC/AHA Lipid Guidelines in patients with Diabetes

Since the release of the 2013 ACC/AHA Guidelines on the Treatment of Blood Cholesterol to Reduce Atherosclerotic  Cardiovascular Risk in Adults, much attention has been placed on potential overtreatment of patients with statins and overuse of higher doses of statins. In our patients with diabetes, these guidelines recommend a moderate intensity statin for those with LDL-C between 70-189mg/dL aged 40-75 yrs without atherosclerotic cardiovascular disease (ASCVD) and a high intensity statin in those with LDL-C between 70-189mg/dL aged 40-75 yrs with an estimated 10 year ASCVD risk of ≥7.5%.1  There is substantial evidence of major benefit to support the use of moderate intensity statin therapy in patients with diabetes.  This evidence is from 2 major trials which showed compelling evidence of decreasing the risk of first major coronary events, coronary revascularization or stroke with atorvastatin 10mg compared to placebo or simvastatin 40mg compared to placebo.2-3

Controversy comes with the recommendation of high intensity statins in patients with estimated 10 year ASCVD risk of ≥7.5%. Little to no evidence exists in this specific population, however the recommendation is made based on extrapolation from those at increased risk without diabetes.  Given the concerns regarding the validity of the new ASCVD risk calculator and possibility of it overestimating the true ASCVD risk of our patients, this recommendation could lead to over treatment with high intensity statins.4  If one were to input the baseline characteristics of our key primary prevention studies in the ASCVD risk calculator, the results indicate that population would have needed high intensity statin therapy based on their risk being >20% considering the trials mostly included men. This is concerning given the potential link between statins and increased risk of diabetes and worsening glycemic control.5-6 Adverse effects of statins are known to be dose related, more frequent in females and possibly greater in the Asian population.7 Additionally, risk calculators were not used to determine eligibility in any of landmark trials investigating the effect of statin therapy on the prevention of cardiovascular disease. Risk calculators are only as good as the population from which they have been derived and there are limitations with each.

Clearly, all patients with diabetes would benefit from statin therapy.  The question is, what dose is necessary to best prevent first cardiovascular events in our patients while minimizing the potential adverse effects? How do you address this in your clinical practice? What risk calculator do you use to assess your patient’s risk?

 

  1. Stone NJ, Robinson JG, Lichtenstein AH, et al. 2013 ACC/AHA Guidelines on the Treatment of Blood Cholesterol to Reduce Atherosclerotic Cardiovascular Risk in Adults. J Am Coll Cardiol. 2014;63:2889-2934
  2. Colhoun HM, Betteridge DJ, Durrington PN, et al. Primary prevention of cardiovascular disease with atorvastatin in type 2 diabetes in the collaborative atorvastatin diabetes study (CARDS):multicenter randomized placebo-controlled trial. Lancet 2004;364:685-96
  3. Collins R, Armitage J, Parish S, et al. MRC/BHF Heart Protection Study of cholesterol-lowering with simvastatin in 5963 people with diabetes: a randomized placebo-controlled trial. Lancet 2003;361:2005-16
  4. Ridker PM, Cook NR. Statins: new American guidelines for prevention of cardiovascular disease. Lancet 2013;382:1762-65
  5. Preiss D, Seshasai SR, Welsh P, et al. Risk of incident diabetes with intensive-dose compared with moderate-dose statin therapy: a meta-analysis. JAMA 2011;305:2556-64
  6. Ergou S, Lee CC, Adler Al. Statins and glycemic control in individuals with diabetes: a systematic review and meta-analysis. Diabetologia 2014;57:2444-52.
  7. Chatzizisis YS, Koskinas KC, Misirli G, et al. Risk Factors and Drug Interactions Presidposing to Statin-Induced Myopathy: Implications for Risk Assessment, Prevention and Treatment. Drug Saf 2010;33:171-187.