Atorvastatin delays first MI for patients with diabetes

Journal of Family Practice, Dec, 2004

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): multicentre randomised placebo-controlled trial. Lancet 2004; 364:685-696.

* CLINICAL QUESTION

Is atorvastatin effective in the primary prevention of cardiovascular disease in adults with diabetes mellitus?

* BOTTOM LINE

In high-risk patients with diabetes, atorvastatin (Lipitor) delays the development of acute coronary events but does not significantly decrease the rate of revascularization or all-cause mortality. (LOE=1b)

* STUDY DESIGN

Randomized controlled trial (double-blinded}

* ALLOCATION

Concealed

* SETTING

Outpatient (any)

* SYNOPSIS

The researchers enrolled 2838 men and women aged 40 to 75 years with type 2 diabetes mellitus of at least 6 months' duration who also had hypertension, retinopathy, microalbuminuria, macroalbuminuria, or current tobacco use. The research team randomly assigned (concealed allocation) patients to receive atorvastatin 10 mg daily (n=1428) or placebo (n=1410), regardless of lipid levels. The main outcome, determined by intention to treat, was a composite of first acute coronary event, coronary revascularization, or stroke.

The study was ended 2 years early because the predetermined threshold for the main outcome was reached. By the time the study was terminated, patients had been evaluated for approximately 3.9 years. During the study, 5.8% of patients taking atorvastatin experienced the composite endpoint compared with 9% of those taking placebo (number needed to treat=32 for 3.9 years; 95% confidence interval, 20-79). However, there was no significant difference in the individual outcomes of all-cause mortality or in the need for coronary revascularization.

The authors of this study state there is no justification for using a threshold level of low-density lipoprotein cholesterol to determine which patients with type 2 diabetes should receive statins. I think this statement is premature. Using their data, only 3% of patients will benefit after 3.9 years. Individual risk-assessment and tailored intervention makes more sense.