Abstract|Mixed Topics 2| Volume 357, SUPPLEMENT 1, e44, October 15, 2015

Fasting blood glucose levels are associated with white matter hyperintensities’ burden in older individuals with and without type 2 diabetes

      Background: The occurrence of white matter hypointensities (WMH) on T2-weighted (FLAIR) MRI scans is widespread in the ageing population and known to be associated with cerebrovascular disease, cardio-metabolic pathology, and increased risk of cognitive decline and dementia. While WMH have been found to be associated with hyperglycaemia in type 2 diabetes (T2D), it is unclear whether fasting blood glucose (FBG) levels in the absence of T2D is associated with higher risk of developing WMH.
      Objectives: Investigate the association between FBG and WMH burden in older individuals living in the community.
      Material and methods: Participants were 401 individuals (aged 60-66 years, 48.6% female) taking part in a large longitudinal study of ageing. FBG levels and WMH measures were obtained at first assessment. T2D classification was based on self-report or a fasting glucose level > =7 mmol/l. Associations were tested with multiple regression analyses while controlling for age, sex, education, smoking, and intra-cranial volume. Institutional Review Board approval was granted.
      Results: Included participants comprised 276 individuals with glucose in the normal range (<5.6 mmol/l), 86 with elevated FBG but without T2D (5.6-6.9 mmol/l), and 39 with T2D. Results showed that higher FBG was associated with greater WMH burden in the whole sample in the right (p = 0.02) but not the left hemisphere and particularly so in the frontal and temporal lobes. Sensitivity analyses indicate that these findings were mostly driven by participants with T2D or impaired FBG levels.
      Conclusion: Impaired FBG levels are associated with increased WMH burden in older community-living individuals with or without T2D.