Study finds ideal blood sugar range for lowering risk of recurrent strokes and heart attacks

Washington: A new study has discovered that for people with diabetes who have had a stroke, there may be ideal blood sugar levels to lower the risk of future vascular diseases such as a stroke or heart attack.

The study’s findings were published in the medical journal ‘Neurology.’

“We know that diabetes is associated with an increased risk of having a first stroke,” said study author Moon-Ku Han, MD, PhD, of Korea’s Seoul National University College of Medicine.

But our results indicate that there is an optimal blood sugar level that may start to minimize the risk of having another stroke, a heart attack or other vascular problems, and it’s right in the 6.8 per cent to 7.0 per cent range,” Han added.

The study involved 18,567 people with diabetes with an average age of 70. All participants were admitted to the hospital for an ischemic stroke, which is caused by a blood clot. Upon admission, researchers used a test called the hemoglobin A1C to determine people’s average blood sugar level over the past two to three months.

This test measures a percentage of hemoglobin proteins in the blood coated with sugar. A level below 5.7 per cent is considered normal;6.5 per cent or higher generally indicates diabetes. The participants had an average A1C of 7.5 per cent.

Researchers then followed up one year later to find out if there was an association between A1C levels with the risk of having another stroke, a heart attack, or dying from these or other vascular causes.

Of all participants, 1,437, or about 8 per cent, had a heart attack or died from the vascular disease within a year of starting the study, and 954, or 5 per cent, had another stroke.

The study found that people admitted to the hospital with A1C levels above the 6.8 per cent to 7.0 per cent range had an increased risk of having a vascular event like a heart attack, as well as having another stroke.

After adjusting for factors like age and sex, researchers found that people’s risk for a heart attack or similar vascular diseases was 27 per cent greater when they were admitted to the hospital with A1C levels above 7.0 per cent, compared to those admitted with A1C levels below6.5 per cent.

People’s risk for having another stroke was 28 per cent greater when admitted to the hospital with A1C levels above 7.0 per cent, compared to those below 6.5 per cent.

“Our findings highlight the importance of keeping a close eye on your blood sugar if you’re diabetic and have had a stroke,” Han said.

A limitation of the study is that people’s blood sugar levels were measured only at the start of the study; no follow-up levels were available.