Prompted by the study, the National Institutes of Health (NIH) immediately halted a massive trial of diabetes and heart disease citing a large number of deaths among patients who pushed their blood sugar level really low.
The study, Action to Control Cardiovascular Risk in Diabetes (ACCORD), was halted 18 months early after 257 deaths were reported among aggressively treated patients of type 2 diabetes compared to 203 among diabetics given more standard care.
Some 10,251 people were enrolled in the ACCORD study with an average participation time of four years, NIH's National Heart Lung and Blood Institute said. The aim of study was to convincingly test whether various aggressive treatment strategies reduce the risk for heart disease - the main cause of death among diabetics.
About half the patients were asked to follow a regimen combining diet and exercise with drugs designed to lower their blood sugar levels to that of the average person with diabetes.
The other group was put on a more intensive regimen designed to drive it closer to that of someone without diabetes. The patients were also divided further into those who also received blood pressure-lowering medication or drugs to improve their cholesterol levels.
However, a group monitoring the study alerted about the number of deaths and it was found that about half the excess deaths were from heart disease.
Elizabeth G. Nabel, director of the National Heart, Lung and Blood Institute said, "As always, our primary concern is to protect the safety of our study volunteers."
"We will continue to monitor the health of the study participants and will seek to determine the cause," she added.
The researchers have also stressed that the disturbing findings would not alter treatment for most diabetics. They also added that reducing blood sugar levels to very low levels might still prove beneficial for other patients, such as those who are younger. This group was not at high risk for heart disease.
If the level of glucose (sugar) in the blood drops below a certain point - about 3.0mmol/l,( millimoles per litre) the condition is called Hypoglycaemia. This causes a number of symptoms such as dizziness, sweating and fatigue that usually go away 10 to 15 minutes after eating sugar.
An estimated 21 million Americans suffer from type 2 diabetes - the most common form of the disease. Diabetes patients' blood sugar levels rise abnormally high, causing a host of serious complications, including nerve damage, amputations, blindness and increased risk for heart attacks and strokes.
