Even for people who do not have diabetes or hyperglycemia, those with higher blood glucose levels are more likely to have memory problems, according to a small study.
The study, published Oct. 23 on the website of the journal Neurology, involved 141 people with an average age of 63 who did not have diabetes or prediabetes. People who were overweight, drank more than 3 1/2 servings of alcohol per day or had memory and thinking impairment were not included in the study.
The researchers used the Rey Auditory Verbal Learning Test to assess participants memory skills, and also tested their blood glucose levels. Participants also had brain scans to measure the size of the hippocampus area of the brain, which plays an important role in memory.
People with lower HbA1c and blood glucose levels were more likely to have better scores on the memory tests. On a test where participants needed to recall a list of 15 words 30 minutes after hearing them, recalling fewer words was associated with higher blood glucose levels. For example, an increase of about 7 mmol/mol of HbA1c was associated with recalling two fewer words. People with higher blood glucose levels also had smaller volumes in the hippocampus.
These results suggest that even for people within the normal range of blood sugar, lowering their blood sugar levels could be a promising strategy for preventing memory problems and cognitive decline as they age, Agnes Flöel, MD, of Charité University Medicine in Berlin, said in a news release. Strategies such as lowering calorie intake and increasing physical activity should be tested.
Neurology is the medical journal of the American Academy of Neurology. Study abstract: www.neurology.org/content/early/2013/10/23/01.wnl.0000435561.00234.ee.short