A new study comes to support the idea that diabetics have high chances of dying because of heart disease or a stroke even after receiving aggressive treatment for lowering their blood-sugar kevels.

The study by the Department of Veterans Affairs was presented Sunday in San Francisco at the annual meeting of the American Diabetes Association. It follows two other studies on the same issue, which were presented Friday at the same meeting and were published online by the New England Journal of Medicine.

It is well known that patients with type 2 diabetes have high levels of blood sugar. That’s why many scientists thought that getting their blood sugar as close to normal, their cardiovascular disease rate would be nearly normal as well. Unfortunately, the results of these three studies failed to meet expectations.

The VA Diabetes Trial shows that hypoglycemia must be avoided in diabetics’ case, as it can lead to heart attack, stroke and death. More specific, the study found that patients who had become severely hypoglycemic in the previous three months were two or three time more likely to suffer a heart attack, stroke or death, the lead author of the study William Duckworth, director of research at the VA Medical Center in Phoenix said.

The previous trials involving more than 20,000 Type 2 diabetes patients had the same result. In fact, one of them, called the ACCORD study, was halted in February because it found that very tightly controlled blood sugar levels were linked to a higher death rate.

The second study called ADVANCE didn’t find a similar danger among patients who lowered their glucose levels. However, the scientists found a 21 percent decrease in kidney problems in patients whose blood sugar was aggressively lowered to normal values.

In conclusion, all three studies failed to confirm a long-sustained hypothesis according to which Type 2 diabetes patients could be protected from cardiovascular disease if they strictly controlled their blood sugar. Cardiovascular disease accounts for 65 percent of deaths among people suffering from this disease.

 Diabetes is  caused by the body’s inability to use or produce the hormone insulin. The disease can lead to heart disease, kidney failure, blindness and amputations, being the sixth-leading cause of death in the U.S. According to the U.S. Centers for Disease Control and Prevention, nearly 21 million Americans have diabetes, most patients having Type 2 diabetes which occurs mainly in adults age 40 and older who are overweight.