Older type 2 diabetics with low blood sugar may have higher mortality rate

In addition to worrying about excessively high blood sugar levels, older adults with type 2 diabetes should be concerned about very low blood glucose levels as well. A new study from University of Chicago researchers has shown that this may result in a modest increase in their risk of death.

The researchers said that their findings underscore the importance of maintaining strict control over blood sugar levels at all times. While the increased mortality risk was moderate, it shows that potentially serious complications can arise, even from low blood sugar levels.

For the study, which was published in the journal Diabetes Care, the researchers analyzed data from 70,000 type 2 diabetics over the age of 60. They tracked participants' medical records for a period of five years.

The results showed, as prior research has established, that those who had persistently high blood glucose levels during this time were more likely to experience complications, such as heart disease, neuropathy and impaired liver function. However, the finding that participants with exceptionally low blood sugar were slightly more likely to die during the study period than those with well controlled readings was more of a surprise.

The researchers said that the study provides evidence that recommendations for blood sugar should be revised. Most guidelines call for diabetics to maintain blood sugar levels, as determined by HbA1c testing, below 7 percent without suggesting any lower range. However, the new findings showed that participants with the best health had blood sugar between 6 and 8 percent.

"We need more evidence regarding how well the 7 percent guideline, which was based on a 1998 British trial that excluded older patients, applies to patients over the age of 60," said Andrew J. Karter, who led the investigation.