Clinical assessment of Alzheimer's disease

The Consortium to Establish a Registry for Alzheimer's Disease (CERAD) was established in 1986 to develop standardized methods to evaluate persons with Alzheimer's disease (AD) and gather clinical, neuropsychological, and neuropathologic information about this illness.

CERAD clinical battery. The clinical assessment protocol(table 1) was designed to provide clinicians with the minimum information necessary to make a confident diagnosis of AD.¹ The battery includes reliable and validated measures or those of time-honored value. Information is obtained through semistructured interviews with the patient and an informant, a general physical and neurologic examination of the patient, and brief cognitive scales. Questions are asked regarding prior illnesses and injuries and symptoms of depression. Other questions cover the history of possible symptoms of dementia, medications that might contribute to such symptoms, and duration of the dementing process. We administer a modified Blessed Rating Scale for Dementia² to determine informant-reported changes in instrumental and basic activities of daily living and the Short Blessed Test³ to measure orientation, memory, and concentration. We evaluate the patient's language, calculation, and visuospatial performance. Laboratory studies include a routine hemogram and biochemical screen, thyroid function test, and vitamin B-12 level. Neuroimaging of the brain by either CT or MRI is required. A protocol for obtaining and reading neuroimages has been developed.⁴ Global severity of dementia is staged in accordance with the Clinical Dementia Rating (CDR) scale.⁵(With evaluation of the cases until death, the stages assessed by the CDR have been validated and expanded to include profound [coded as 4] and terminal[coded as 5].)⁶ Diagnostic criteria for AD are those proposed by the National Institute of Neurological and Communicative Disorders and Stroke/Alzheimer's Disease and Related Disorders Association(NINCDS/ADRDA)⁷ modified to require memory loss of at least 12 months' duration (instead of 6 months), and …