There is a strong link in people with diabetes who also have high cholesterol Cardiovascular disease is much more prevalent if their Hemoglobin A1c is chronically elevated. This significant contribution by elevated HbA1c to increased CVD is independent of statin therapy, and thus requires appropriate HbA1c management in addition to lipids reduction. It is vitally important that any individual with known heart disease and diabetes gets their hemoglobin A1c measured approximately 4 times per year by their primary health care provider. Once a year is not enough. Tight control is imperative. If the blood sugars are constantly running high the vessels that deliver blood to the heart are constantly inflamed setting the stage for further heart issues.
There are many hemoglobin A1c calculators can be found on the internet. here is Medscapes version