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

•What is the primary question addressed by this study?Can we evaluate the definition of agitation in cognitive impairment and dementia put forth by the International Psychogeriatric Association (IPA) in a well-characterized cohort of community-dwelling older individuals?•What is the main finding of this study?Agitation, present in community-dwelling older individuals across the spectrum of cognitive impairment and dementia severity and recognized by clinicians and by assessment tools such as the Neuropsychiatric Inventory-Questionnaire (NPI-Q) ranges from 14% to 49%. The condition is associated with significant functional impairment as measured by activities of daily living and is not solely attributable to any other single psychiatric diagnosis.•What is the meaning of the finding?Agitation is a frequent problem in community-dwelling older individuals across the spectrum of cognitive impairment; it is aligned with symptoms in the IPA definition including excess functional disability, and is recognized by clinicians and family members or other informants. 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. 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. 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