Methylphenidate for Apathy in Veterans With Parkinson's Disease

Apathy Evaluation Scale (AES)

This measure is an 18-item scale initially developed as a method for measuring apathy resulting from brain-related pathology.

Clinical Global Impression of Change (CGIC)

The CGIC is a systematic method, developed for the Alzheimer's disease (AD) setting to assess clinically significant change in a clinical trial as viewed by an independent, skilled, and experienced clinician and has been used as an outcome in Parkinson disease trials

Alzheimer's Disease Assessment Scale-Cognitive subscale (ADAS-Cog)

This scale was developed specifically to assess cognitive functioning in patients with Alzheimer's disease but has also been used in Parkinson disease.65 It is widely used in clinical trials, and its sensitivity in detecting cognitive changes has been demonstrated in a number of studies. Scores are obtained for orientation, word-list recall, and recognition, object naming, ability to follow simple requests, ideational and constructional praxis, and expressive language. Higher scores indicate worse performance.

Continuous Performance Test (CPT)

The CPT was developed to study vigilance or selective attention. In its original form, letters were presented to participants visually one at a time at a fixed rate. The subjects were to press a lever whenever the target letter X appeared and to not press the lever if any other letter was shown. This is called the X-CPT version, and Beck et al found that this version had adequate classification accuracy. Various modifications of the basic X-CPT have been adopted, including changing the target to a number or picture, or a letter series. The CPT version used for this study will be Conner's CPT Version II. The targets are letters and patients do not respond to the letter X (not-X-CPT).

Trail Making Test (TMT)

The TMT is composed of visual search and sequencing tasks that are heavily influenced by executive functioning (concentration, resistance to distraction, and cognitive flexibility/set-shifting) and attention. These easily administered tasks are extremely sensitive to neuropsychological deficits such as frontal lobe deficits, problems with psychomotor speed, visual search, and sequencing deficits. The Test has two parts: A and B. In Part A, subjects connect numbers in order on a piece of paper as quickly as possible. Part A provides a baseline for processing speed for interpretation of the second part, Part B. For Part B, subjects connect numbers and letters alternately in order such that the connections are 1-A-2-B-3-C and so on. Both parts are timed. Lower times are better.

Neuropsychiatric Inventory (NPI)

The NPI assesses the type and severity of behavioral disturbances in dementia. The inventory evaluates 12 domains of neuropsychiatric symptoms (NPS): apathy, agitation, delusions, hallucinations, depression, euphoria, aberrant motor behavior, irritability, disinhibition, anxiety, sleeping, and eating. Frequency (1 = occasionally, less than once/week; 2 = often, about once per week; 3 = frequently, more than once a week; 4 = very frequently, once or more/day or continuously) and severity (1 = mild, 2 = moderate, 3 = severe) scales in each domain are scored based on responses from an informed caregiver involved in the patient's life. The NPI also includes a 5-point rating used to quantify caregiver distress with the patient's NPS symptoms. To obtain an NPI score for each domain, the severity score and the frequency score are multiplied, and the caregiver distress ratings of each domain are added up.