This turns out to be pure bullpucky.
A study published in Diabetes Care this month followed for ten years 4,410 patients aged 30–74 years: 2,260 with type 2 diabetes without coronary heart disease recruited in 53 primary health care centers and 2,150 people who had already had a heart attack but did not have diabetes.
Here's what they found:
The adjusted hazard ratios (HRs) [i.e. risk] for 10-year coronary heart disease incidence and for cardiovascular mortality were significantly lower in men and women with diabetes than in myocardial infarction patients... All diabetic patient subgroups had significantly fewer events than myocardial infarction patients.Long-Term Cardiovascular Risk in Type 2 Diabetic Compared With Nondiabetic First Acute Myocardial Infarction Patients: A population-based cohort study in southern Europe J. Francisco Cano et al. Diabetes Care, September 2010 vol. 33 no. 9 2004-2009. doi: 10.2337/dc10-0560
Don't expect the statin drug reps to tell this to your family doctor. Selling the idea that people with diabetes "already have heart disease" has been very profitable to the drug companies. But if you've been worrying yourself sick over it, relax.
In fact, given the close relationship of post-meal blood sugar levels to heart attack incidence in all groups of people--those with and without diabetes diagnoses, it's very possible that people with diabetes who keep their blood sugars under 140 mg/dl as much as possible will have fewer heart attacks than their "healthy" peers.
You can learn more about how blood sugar level predicts heart attack far better than cholesterol levels here: A1c and Post-Meal Blood Sugars Predict Heart Attack