title: Glucose regulation, cognition, and brain MRI in type 2 diabetes: a systematic review.
abstract: Type 2 diabetes is associated with cognitive dysfunction and structural brain changes. Abnormalities in glucose regulation are involved in several complications related to type 2 diabetes, but their role in these cerebral complications is unclear. We systematically reviewed studies of the association between glucose regulation (glycaemia, hypoglycaemic events, insulin concentration, insulin resistance, and glucose-lowering treatment) and cognitive function and brain abnormalities on MRI in people with type 2 diabetes. The 86 papers included showed that glycaemia, particularly high HbA1c concentration and glucose variability, are negatively associated with cognitive function in people with type 2 diabetes without dementia. However, the strength of this association is weak, and HbA1c generally accounted for less than 10% of the variance in cognition. Importantly, few studies have measured long-term cerebral outcomes, such as dementia and structural brain changes on MRI, and the effect of glucose-lowering treatment on these outcomes. More randomised controlled trials are needed to establish the effect of glucose-lowering treatment on long-term cognitive function in people with type 2 diabetes.
authors.affiliation: Department of Internal Medicine and Cardiovascular Research Institute, Maastricht University Medical Center, Maastricht, Netherlands.
authors.forename: Stefan L C
authors.initials: SLC
authors.lastname: Geijselaers
authors.affiliation: Department of Internal Medicine and Cardiovascular Research Institute, Maastricht University Medical Center, Maastricht, Netherlands.
authors.forename: Simone J S
authors.initials: SJS
authors.lastname: Sep
authors.affiliation: Department of Internal Medicine and Cardiovascular Research Institute, Maastricht University Medical Center, Maastricht, Netherlands.
authors.forename: Coen D A
authors.initials: CDA
authors.lastname: Stehouwer
authors.affiliation: Department of Neurology, Brain Center Rudolf Magnus, University Medical Center Utrecht, Utrecht, Netherlands. Electronic address: g.j.biessels@umcutrecht.nl.
authors.forename: Geert Jan
authors.initials: GJ
authors.lastname: Biessels
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D001786:Blood Glucose; D001921:Brain / Q000473:pathology; D003072:Cognition Disorders / Q000209:etiology; D003924:Diabetes Mellitus, Type 2 / Q000150:complications* / Q000503:physiopathology / Q000523:psychology; D005947:Glucose / Q000378:metabolism; D006442:Glycated Hemoglobin / Q000378:metabolism; D006801:Humans; D007003:Hypoglycemia / Q000209:etiology; D008279:Magnetic Resonance Imaging; D008875:Middle Aged
chemical_list: D001786:Blood Glucose; D005947:Glucose; D006442:Glycated Hemoglobin; C517652:hemoglobin A1c protein, human