Clock drawing and frontal lobe behavioral effects of memantine in Alzheimer's disease: a rater-blinded study

Caregivers of Alzheimer's disease patients treated with memantine have reported improved frontal lobe behaviors. The present study examined these possible improvements in executive functioning using rater-blinded scoring of a clock-drawing test. Fifty-one Alzheimer's disease patients were treated with open-label memantine for 10 weeks. Clock drawing and Mini-Mental State Examination data were collected before and after treatment. Clock drawing improved significantly with treatment, whereas Mini-Mental State Examination data did not. Twenty-seven patients judged as improved in frontal lobe behaviors by caregivers demonstrated a statistically significant improvement in clock drawing to command, whereas 24 patients judged to be unchanged or worse with memantine in their frontal lobe behaviors had no change in their clock drawing and had worsening on their Mini-Mental State Examination. The current findings suggest that memantine improves frontal lobe behavior in some Alzheimer's disease patients and that clock drawing to command may be sensitive to these improvements.