CSF biomarkers and medial temporal lobe atrophy predict dementia in mild cognitive impairment

Abstract

Objective To study CSF biomarkers, beta-amyloid 1-42 (Aβ 1-42) and tau, and medial temporal lobe atrophy (MTA) on MRI in their ability to predict dementia in patients with mild cognitive impairment (MCI). Methods Fifty-nine MCI patients (49% male, mean age 69 ± 8), follow-up 19 months, were included. Baseline CSF levels of Aβ 1-42, tau and MTA-score were dichotomized. Results Thirty-three (56%) of the MCI patients progressed to dementia, 30 of which had Alzheimer's disease. Lower CSF Aβ 1-42 level, higher CSF-tau and higher MTA-scores at baseline were found in progressed patients. Cox proportional hazards models revealed that abnormal CSF Aβ 1-42, CSF tau and MTA were significantly associated with dementia at follow-up (hazard ratio (95% confidence interval): 4.0 (1.3–12.1), 5.9 (1.6–21.7) and 2.1 (1.0–4.6)). A fourfold higher risk was found for patients with both abnormal CSF biomarkers and MTA compared to patients with either test abnormal. Ninety-four percent of patients with both abnormalities converted to dementia. Conclusions These findings suggest an added value of CSF to MRI in the diagnostic work up of patients presenting at a memory clinic.