Agitation in Cognitive Disorders: Use of the National Alzheimer's Coordinating Center Uniform Data Set (NACC-UDS) to Evaluate International Psychogeriatric Association Definition

Abstract

Objective: Consensus-based definition of agitation by the International Psychogeriatric Association (IPA) has not been evaluated in community-based samples who are not preselected for behavioral disturbances. Here, we use a well-characterized cohort of community-dwelling older adults with cognitive impairment to assess the IPA criteria associated with agitation to evaluate the construction of this diagnostic entity.

Methods: We used the National Alzheimer Coordinating Center Unified Data Set (NACC-UDS) to construct the IPA consensus-based provisional definition of agitation in cognitive impairment (N = 19,424). We used clinician diagnosis of agitation as a gold standard in those with mild cognitive impairment and dementia and used the Neuropsychiatric Inventory-Questionnaire to define agitation symptoms and standardized assessments of function (including the Functional Assessment Scale and Clinical Dementia Rating Scale Sum of Boxes) to assess "excess disability." We also examined patterns of psychiatric comorbidities to determine if they were consistent with IPA criteria.

Results: There was agreement between the selected NPI measure of agitation and clinician judgment (sensitivity = 0.79, specificity = 0.69, Cohen's Kappa = 0.304). More than 84% of those with clinician judgment of agitation and 74% of those meeting the scale-based definition of agitation demonstrated excess social/functional disability. Comorbid psychiatric symptoms were present in 38% of the sample without agitation and higher in those with agitation by either definition.

Conclusion: Agitation ranges between 15% and 48% in those with cognitive impairment. The pattern of level of excess disability and the presence of comorbid psychiatric symptoms is consistent with the profile of published definitions.

Keywords: Agitation; Alzheimer's disease; International Psychogeriatric Association (IPA); Neuropsychiatric Inventory-Questionnaire (NPI-Q); dementia.