Neurovascular coupling in Alzheimer patients: Effect of acetylcholine-esterase inhibitors

Dualistic effects of acetylcholine-esterase inhibitors on neuronal as well as vasoregulative function have been debated. This study investigated for the first time effects of medication on both components. Visually evoked potentials and resultant hemodynamic responses were assessed in Alzheimer patients (n = 31) without vascular lesions in a MRI scan and compared to controls (n = 20). After baseline recordings (AD0) tests were repeated under 2 × 1.5 to 2 × 3 mg (AD1) and 2 × 4.5 to 2 × 6 mg (AD2) rivastigmine/d. Long-term effects were investigated under 6 months of medication (AD2L). The ADAS, MMSE and DEMTECT were used to assess cognitive function at AD0, AD2 and AD2L. Improvement in vasoregulative function was independent from changes in evoked potentials. Acetylcholine-esterase inhibitors demonstrate substantial vascular effects in humans, which are independent from changes in neuronal function.