Assessment of Psychosis in Alzheimers Disease

Using one of the neuropsychiatric batteries to help determine target symptoms should occur after reversible medical conditions (e.g., occult infection, metabolic imbalance) and iatrogenic or medication-induced symptom production are ruled out. Several assessment batteries are available to identify and reliably quantify target symptoms for treatment.

The most common rating scales available to measure neuro-psychiatric symptoms of AD include the Neuropsychiatric Inventory (NPI; Cummings et al., 1994), NPI/NH (Wood et al., 2000), Behavioral Pathology in Alzheimer's Disease (BEHAVE-AD; Reisberg, 1984), the Gottfries-Brane-Steen Scale (Gottfries, Brane, & Steen, 1982), CERAD Behavior Rating Scale (Tariot et al., 1995), the Cohen-Mansfield Agitation Inventory (Cohen-Mansfield et al., 1989), and the Columbia University Scale for Psychopathology (CUSPAD) (Devanand et al., 1992).

The NPI is a caregiver-based instrument (Cummings et al., 1994) that has become widely used in the research setting. The NPI is a valid and reliable means of assessing neuropsychiatric symptoms (e.g., agitation, apathy, depression, anxiety, delusions, hallucinations, irritability, and delusions) in patients with dementia, with a decision tree approach making it very useful (Cummings & McPherson, 2001). The NPI's psychometric properties include strong reliability and validity established in a number of studies and a variety of settings and demonstrated sensitivity to change in several clinical trials evaluating psychopharmacologic approaches to treat behavioral complications in dementia or AD (McKeith, Fairbairn, Perry, & Thompson, 1994; Street et al., 2000, 2001; Tariot, Solomon, et al., 2000). The NPI can be administered at every visit by a trained evaluator, monitoring for symptom improvement.

The Neuropsychiatric Inventory/Nursing Home Version (NPI/NH) is a caregiver-rated scale administered in nursing home patients. The NPI/NH, like the NPI, is a structured interview with a few minor modifications assessing the frequency and severity of 12 psychobehavioral symptoms associated with dementia (Wood et al., 2000). The NPI/NH allows professional staff of the care facility to act as the informant, rather than obtaining information from the caregiver of a community-dwelling elderly person as required to complete the NPI.

The BEHAVE-AD (Reisberg et al., 1987) is a caregiver-rated instrument based on a 25-item scale that measures behavioral disturbances in seven major categories (delusions, hallucinations, activity disturbances, aggressiveness, sleep disturbance, affective disturbance, and anxiety). Each symptom is scored on a four-point scale of severity, where 0 = not present to 4 = most severe. The BEHAVE-AD scale specifically measures the occurrence and severity of behavioral problems in patients with AD and has been found to be a reliable scale that has been used in clinical trials (De Deyn et al., 1999; Katz et al., 1999; Montaldi, Brooks, & McColl, 1990; Sclan, Saillon, Franssen, Hugonot-Diener, & Saillon, 1996).

The Gottfries Scale is a caregiver-completed scale that measures behavioral disturbances, cognitive disturbances, and some functional impairment (Gottfries et al., 1982). This scale is not very specific in terms of the nature of behavioral disturbances, has some features that may make it difficult to train raters, and has rarely been used in the United States.

The Behavioral Rating Scale for Dementia (BRSD) of the Consortium to Establish a Registry for Alzheimer's Disease (CERAD; Tariot et al., 1995) scale derives target symptoms; it is comprehensive, specifically measuring the occurrence and severity of behavioral problems in patients with AD. Unfortunately, it is very long (48 questions), requires training to administer, and is impractical compared to the NPI.

The Cohen-Mansfield Agitation Inventory (CMAI ) is excellent for detailing patterns of agitation in nursing home patients with AD, but it cannot be used in outpatients because of the intensive observation by an informant that is required (Cohen-Mansfield et al., 1989; Koss et al., 1997). This assessment tool focuses only on agitation and does not assess psychosis.

The CUSPAD is useful to assess psychopathology, but it does not have quantitative ratings for items and, hence, is not appropriate for repeated testing to monitor efficacy of a treatment (Devanand et al., 1992). The CUSPAD criteria provide for the definition of a delusion as " broad" (does not accept caregiver's correction of the false belief ) and "narrow" (does not accept caregiver's correction of the false belief, and occurs more than three times per week). Hallucinations are defined as " vague" or "clear." The presence of either a delusion (narrow definition) or hallucination (clear) on the CUSPAD is required for a person to have "psychosis."

Anxiety and Depression 101

Anxiety and Depression 101

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