Purpose

To assess prior need for lipid lowering therapy in patients with type 2 diabetes.

Background/Hypothesis

At present, lipid lowering therapy, usually with a HMG-CoA reductase inhibitor or "statin", is recommended therapy for selected patients with type 2 DM. The use of statins for primary prevention of CVD is not clear. Some primary prevention studies have found a statistically significant benefit but others have not (CARDS and ASPEN).

Although LDL has traditionally been a key marker of CVD risk and thus a guide to statin treatment, in recent years apolipoprotein B (apoB) has emerged as an independent risk factor for CVD.

In a recent study Tildesley H. et al. showed that in 500 patients with type 2 DM not on lipid lowering therapy there was discordance between LDL and apoB values. Specifically, it was found that among patients who fail to achieve the LDL-C target, 13% of men, 24% of women less than 50 and 13% of women greater than 50 meet the apoB target. In other words, while the LDL level would indicate treatment, the apoB level would not.

Based on these observations there is good reason to believe that a significant number of patients with type 2 DM may be on lipid lowering therapy needlessly. As stated above, primary prevention statin trials are not anonymously positive (ASPEN and CARDS) and CVD events are not as prevalent as thought-this is demonstrated by the recent results from ACCORD. Latest results from ACCORD show a CVD death rate of 1.1% and 1.4% in the standard glycemic control group and the intensive glycemic control group respectively. As discussed previously, Tildesley et al. found that at least 13% of all patients have an under target apoB but an over target LDL. This, taken with the notion that apoB is a stronger predictor of CVD events than LDL would lead one to believe that at least 13% of patients are being treated unnecessarily. Based on these observations there is good reason to believe that a significant number of patients with type 2 DM may be on lipid lowering therapy needlessly.

Objectives

The investigators propose to measure lipid parameters during lipid lowering therapy and compare this with lipid parameters at one and two months after discontinuation of therapy in selected patients with type 2 DM at low risk for CVD. Lipid parameters to be measured include: HDL-cholesterol, LDL-cholesterol, triglycerides, total cholesterol, total cholesterol:HDL-cholesterol ratio and apoB. As well, A1C will be measured.