title: Continuous glucose monitoring and cognitive performance in type 2 diabetes.
abstract: BACKGROUND
  Type 2 diabetes is associated with reductions in cognitive function that are associated with glycated hemoglobin (HbA1c) levels, but there is no information on whether cognition is related to postmeal glucose spikes. We explored the relationship of cognition to glucose levels measured by a continuous glucose monitoring system (CGMS) both before and after a weight loss diet.
  
  
  METHODS
  Forty-four white subjects with type 2 diabetes (59.0 ± 6.2 years old; body mass index, 32.8 ± 4.2 kg/m(2); HbA1c, 6.9 ± 1.0%) completed an 8-week energy-restricted (approximately 6-7 MJ, 30% deficit) diet. Cognitive functioning (short-term memory, working memory, speed of processing [inspection time], psychomotor speed, and executive function) was assessed during four practice sessions, baseline, and Week 8. Parallel glucose levels were attained using the CGMS in 27 subjects. Outcomes were assessed by fasting blood glucose (FBG), postprandial peak glucose (G(max)), time spent >12 mmol/L (T > 12), and 24-h area under the glucose curve (AUC(24)).
  
  
  RESULTS
  Despite a fall in FBG of 0.65 mmol/L after 8 weeks, digits backward results correlated with FBG at both Week 0 and Week 8 (r = -0.43, P < 0.01 and r = -0.32, P < 0.01, respectively). Digits forward results correlated with FBG (r = -0.39, P < 0.01), G(max) (r = -0.46, P < 0.05), and AUC(24) (r = -0.50, P < 0.01) at Week 0 and FBG (r = -0.59, P < 0.001), G(max) (r = 0.37, P = 0.01), AUC(24) (r = -0.41, P < 0.01), and percentage weight loss (r = 0.31, P < 0.01) at Week 8. Cognitive function was not altered by weight loss, gender, baseline lipid levels, or premorbid intelligence levels (National Adult Reading Test).
  
  
  CONCLUSIONS
  FBG, G(max,) and AUC(24) were related to cognitive function and an energy-restricted diet for 8 weeks did not alter this relationship.
authors.affiliation: Commonwealth Scientific and Industrial Research Organization, Human Nutrition, Adelaide, South Australia, Australia. karma.pearce@unisa.edu.au
authors.forename: Karma L
authors.initials: KL
authors.lastname: Pearce
authors.forename: Manny
authors.initials: M
authors.lastname: Noakes
authors.forename: Carlene
authors.initials: C
authors.lastname: Wilson
authors.forename: Peter M
authors.initials: PM
authors.lastname: Clifton
mesh_terms: D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D001315:Australia / Q000453:epidemiology; D001786:Blood Glucose / Q000378:metabolism*; D015190:Blood Glucose Self-Monitoring; D015992:Body Mass Index; D003071:Cognition; D003924:Diabetes Mellitus, Type 2 / Q000097:blood* / Q000453:epidemiology / Q000503:physiopathology; D004038:Diet, Reducing; D004040:Dietary Carbohydrates / Q000097:blood*; D005215:Fasting / Q000097:blood*; D005260:Female; D038321:Glycemic Index; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic; D019518:Postprandial Period
chemical_list: D001786:Blood Glucose; D004040:Dietary Carbohydrates