Relationship between baseline glycemic control and cognitive function in individuals with type 2 diabetes and other cardiovascular risk factors: the action to control cardiovascular risk in diabetes-memory in diabetes (ACCORD-MIND) trial.
OBJECTIVE
Diabetes is associated with cognitive decline and dementia. However, the relationship between the degree of hyperglycemia and cognitive status remains unclear. This was explored using baseline cognitive measures collected in the ongoing Memory in Diabetes (MIND) substudy of the Action to Control Cardiovascular Risk in Diabetes (ACCORD) trial.


METHODS
The relationship of A1C and fasting plasma glucose (FPG) levels to performance on four cognitive tests was assessed, adjusting for age and other determinants of cognitive status. The tests were the Digit Symbol Substitution Test (DSST), Mini Mental Status Examination (MMSE), Rey Auditory Verbal Learning Test, and Stroop Test.


RESULTS
A statistically significant age-adjusted association was observed between the A1C level and the score on all four cognitive tests. Specifically, a 1% higher A1C value was associated with a significant 1.75-point lower DSST score (95% CI -1.22 to -2.28; P < 0.0001), a 0.20-point lower MMSE score (-0.11 to -0.28; P < 0.0001), a 0.11-point lower memory score (-0.02 to -0.19, P = 0.0142), and a worse score (i.e., 0.75 s more) on the Stroop Test (1.31-0.19, P = 0.0094). The association between the DSST score and A1C persisted in all multiple linear regression models. FPG was not associated with test performance.


CONCLUSIONS
Higher A1C levels are associated with lower cognitive function in individuals with diabetes. The effect of glucose lowering on cognitive function will be determined by the ongoing ACCORD-MIND trial.
Cukierman-Yaffe
Tali
T
Gertner Institute for Epidemiology and Health Policy Research, Endocrinology Institute Sheba Medical Center, Sackler School of Medicine, Tel-Aviv University, Tel-Aviv, Israel. cukierm@mcmaster.ca
Gerstein
Hertzel C
HC
Williamson
Jeff D
JD
Lazar
Ronald M
RM
Lovato
Laura
L
Miller
Michael E
ME
Coker
Laura H
LH
Murray
Anne
A
Sullivan
Mark D
MD
Marcovina
Santica M
SM
Launer
Lenore J
LJ
D001786:Blood Glucose / Q000378:metabolism*; D002318:Cardiovascular Diseases / Q000453:epidemiology; D003071:Cognition; D003924:Diabetes Mellitus, Type 2 / Q000097:blood* / Q000150:complications / Q000523:psychology*; D003925:Diabetic Angiopathies / Q000453:epidemiology; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D008297:Male; D008568:Memory; D008609:Mental Status Schedule; D008875:Middle Aged; D011581:Psychological Tests; D012044:Regression Analysis; D015203:Reproducibility of Results
D001786:Blood Glucose; D006442:Glycated Hemoglobin