title: Higher Fasting Plasma Glucose is Associated with Increased Cortical Thinning Over 12 Years: The PATH Through Life Study.
abstract: Recent evidence suggests that type 2 diabetes (T2D) is associated with accelerated brain ageing, consistent with the observation of increased risk of cognitive impairment and dementia in affected individuals. Even non-diabetic individuals with impaired fasting plasma glucose (IFG) levels have shown increased cerebral atrophy, compared to individuals with normal glucose levels. We tested whether longitudinal rates of age-related cortical thinning were associated with fasting plasma glucose levels in a large sample (n = 322) of early-old age individuals (60-66 years) who were scanned with magnetic resonance imaging (1.5 T) on up to four occasions over 12 years. Higher plasma glucose levels (measured on up to three occasions) were associated with increased cortical thinning in individuals with T2D as well as those with IFG, with a similar trend for individuals with normal fasting glucose (NFG) levels. Across groups, a 1 mmol/l increase in plasma glucose (above 5 mmol/l in NFG and IFG and above 6.1 mmol/l in T2D) resulted in a 10-13% increase in annual cortical thinning. Increased cortical thinning was detected in insular cortex, as well as posterior cingulate, parahippocampus and medial orbitofrontal cortex. Our results provide support for the idea that raised plasma glucose levels, even in the normal range, are associated with accelerated age-related cortical atrophy.
authors.affiliation: Centre for Research on Ageing, Health and Wellbeing, The Australian National University, Building 54, Mills Rd, Canberra, ACT, 0200, Australia. marnie.shaw@anu.edu.au.
authors.forename: Marnie E
authors.initials: ME
authors.lastname: Shaw
authors.affiliation: Centre for Research on Ageing, Health and Wellbeing, The Australian National University, Building 54, Mills Rd, Canberra, ACT, 0200, Australia.
authors.forename: Julia
authors.initials: J
authors.lastname: Nettersheim
authors.affiliation: Centre for Healthy Brain Ageing, University of New South Wales, Sydney, NSW, Australia.
authors.forename: Perminder S
authors.initials: PS
authors.lastname: Sachdev
authors.affiliation: Centre for Research on Ageing, Health and Wellbeing, The Australian National University, Building 54, Mills Rd, Canberra, ACT, 0200, Australia.
authors.forename: Kaarin J
authors.initials: KJ
authors.lastname: Anstey
authors.affiliation: Centre for Research on Ageing, Health and Wellbeing, The Australian National University, Building 54, Mills Rd, Canberra, ACT, 0200, Australia.
authors.forename: Nicolas
authors.initials: N
authors.lastname: Cherbuin
mesh_terms: D000368:Aged; D001284:Atrophy; D001786:Blood Glucose / Q000378:metabolism*; D001921:Brain / Q000000981:diagnostic imaging / Q000473:pathology; D002540:Cerebral Cortex / Q000000981:diagnostic imaging* / Q000473:pathology; D003924:Diabetes Mellitus, Type 2 / Q000000981:diagnostic imaging* / Q000378:metabolism; D005215:Fasting / Q000378:metabolism; D005260:Female; D006801:Humans; D006943:Hyperglycemia / Q000000981:diagnostic imaging* / Q000378:metabolism; D008279:Magnetic Resonance Imaging; D008297:Male; D008875:Middle Aged
chemical_list: D001786:Blood Glucose
keywords: Ageing; Cortical thickness; Fasting plasma glucose; Impaired fasting glucose; Longitudinal; MRI; Risk factors; T2D; Type 2 diabetes