Glucose Control Helps Cognitive Function in Stroke Patients with Diabetes

March 30, 2020
Kenny Walter

For every 1% higher baseline A1C, there was a 0.06 lower standardized CASI z-score.

Glucose control might be a key measure in maintaining cognitive function for patients with type 2 diabetes who suffered a lacunar stroke.

A team, led by Tali Cukierman-Yaffe, MD, a physician and researcher at the Sheba Medical Center and the Sackler School of Medicine of Tel Aviv University, assessed the relationship between glycosylated hemoglobin (A1C) and cognitive function in individuals with type 2 diabetes following a lacunar stroke.

Both lacunar strokes and diabetes are considered risk factors for dementia and cognitive dysfunction. Researchers believe decreasing modifiable risk factors for cognitive dysfunction in individuals with type 2 diabetes who experienced a lacunar infarct can be beneficial for the public health.

Lacunar strokes are a common type of stroke that occurs deep in the brain when an artery that provides blood to the brain’s deep structures is blocked.

The investigators measured the effect of baseline and follow-up A1C on the baseline and the change in Cognitive Assessment Screening Instrument (CASI) score over time among 942 patients at least 30-years old with a median of 2 cognitive assessments. The data was planned for presentation at ENDO.

Each individual included in the study had diabetes a lacunar stroke and participated in the Secondary Prevention of Small Subcortical Strokes (SPS3) trial.

The investigators found every 1% higher baseline A1C was linked to a 0.06 lower standardized CASI z-score (95% CI, -0.101 to -0.018). They also found higher baseline A1C values were linked to lower CASI z-scores over time (P = 0.037).

A 1% increase in A1C over time was linked with a CASI score decrease of 0.021 (95% CI, -0.0043 to -0.038) during follow-up examinations.

After adjusting for age, sex, education, race, depression, hypertension, hyperlipidemia, BMI, CVD, OSA, diabetic retinopathy, nephropathy insulin use, and White Matter Abnormalities, the findings remained statistically significant.

“This analysis of 942 individuals with diabetes after a lacunar stroke demonstrates a relationship between A1C and change in cognitive scores over time,” the authors wrote. “Intervention studies are needed in order to delineate if better glucose control could slow the rate of cognitive decline in this high risk population.”

American and Chinese type 2 diabetes populations are at similar risk for memory impairment and dementia, according to past research from the Mayo Clinic.

The investigators used two large, ongoing population based studies focusing on aging to recruit 3,400 Chinese adults and 3,700 American adults over the age of 50 years. Both of the studies used on site and in person evaluations to test cognition capabilities of the patients.

Even after the researchers adjusted for age, gender, education, and vascular problems, diabetes remained a risk for cognitive decline in both cultures. American and Chinese patients with diabetes specifically performed worse on tasks measuring executive function — the ability to make decisions, plan, and problem solve, typically associated with the brain’s frontal lobe – compared to their nondiabetic counterparts on the same tests.

Better glucose control might be able to help patients suffering from diabetes.

“As the population is aging, the prevalence of diabetes and stroke is increasing, and both diseases are risk factors for cognitive dysfunction and dementia,” Cukierman-Yaffe said in a statement. “Identifying modifiable risk factors that are associated with cognitive dysfunction in people with type 2 diabetes who experience a lacunar stroke has major public health implications.”