Randomised controlled trial of memantine versus placebo in Parkinson's disease dementia

Neuropsychological function including measures of:
1. Global cognitive impairment with emphasis on subcortical functions as assessed by the Dementia Rating Scale (DRS)(Mattis, 1988). This scale examines five areas including: attention, initiation and perseveration, construction, conceptual ability, and memory (verbal and visual).
2. Psychomotor speed and tracking as assessed by Trail Making Test, Part A and B (TMT) (Reitan, 1958).
3. Executive function as assessed by verbal fluency (Monsch et al., 1994).

1. Parkinsonian motor symptoms as measured by:
1.1. The Unified Parkinson’s Disease Rating Scale, motor subscore (items 18-31)(UPDRS-motor)(Fahn et al., 1987) for assessment of baseline and change in motor symptoms. This will administered during the “on” phase or no sooner than 30minutes after administration of anti-Parkinsonian medications.
1.2. The Hoehn-Yahr Scale (HYS)(the same as UPDRS, Part V(Hoehn and Yahr, 1967) for assessment of stage of motor severity in PD (range “0” for no signs of disease to “5” wheelchair bound or bedridden).
2. Psychiatric symptoms as measured by:
2.1. Neuropsychiatric Inventory (NPI)(Cummings et al., 1994).
2.2. Cornell Depression Rating Scale (CDRS)(Alexopolous, 1988).
2.3. Hamilton Rating Scale for Depression (Hamilton 1960).
3. Functional ability as measures by the Parkinson’s Disease Questionnaire (PDQ-39) (Jenkinson et al., 1998).
4. Global measure of change as assessed by the Clinician’s Interview Based Impression of Change (CIBIC+).