• glucose;
  • HbA1c;
  • dementia;
  • tau;
  • amyloid

OBJECTIVES: To determine the association between markers of glycemia and cerebrospinal fluid (CSF) amyloid β 1–42 (Aβ42) and tau levels in patients attending a memory clinic.

DESIGN: Cross-sectional study.

SETTING: Memory clinic.

PARTICIPANTS: Two hundred forty-five consecutive patients attending a memory clinic. Clinical diagnoses were subjective cognitive complaints (n=91), mild cognitive impairment (n=62), Alzheimer's disease (n=58), and other dementia (n=34). Twenty-one patients had diabetes mellitus.

MEASUREMENTS: Glycosylated hemoglobin (HbA1c); fasting blood glucose levels; and CSF levels of Aβ42, total tau, and p-tau 181.

RESULTS: In regression analyses across the whole study sample adjusted for age, sex, and diagnostic group, there was no relationship between HbA1c or fasting glucose and CSF tau, p-tau 182, or Aβ42 levels. Stratification for diabetes mellitus did not change the results.

CONCLUSION: These observations do not support the hypothesis that the association between dysglycemia and impaired cognitive functioning is mediated through aberrant amyloid or tau metabolism.