Down syndrome and Alzheimer disease: response to donepezil.

BACKGROUND Individuals with Down syndrome who develop Alzheimer disease may show an improvement in cognitive functioning after treatment with acetylcholinesterase inhibitors. OBJECTIVE To determine whether individuals with Down syndrome and Alzheimer disease will show improvement after institution of donepezil treatment. DESIGN A nonrandomized controlled trial using donepezil in a pilot study format. SETTING Academic medical center. PATIENTS Convenience sample of 6 treated patients with Down syndrome and 9 closely matched historical control subjects. INTERVENTION Oral administration of donepezil for a 5-month period. PRIMARY OUTCOME MEASURE The Down Syndrome Dementia Scale. RESULTS Significant improvement in dementia scores for the treated group during a 3- to 5-month period (P =.03). CONCLUSIONS Acetylcholinesterase inhibitors may be helpful in reversing the symptoms of dementia during early and middle stages of cognitive decline. These findings support the rationale for a more extensive study of the efficacy of acetylcholinesterase inhibitors in Down syndrome dementia.