PREVALENCE OF NEUROPSYCHIATRIC SYMPTOMS ACROSS THE COGNITIVE SPECTRUM AND THEIR IMPACT ON FUTURE COGNITIVE DECLINE: Session 203

Abstract

In the recently published National Institute on Aging and Alzheimer's Association (NIA-AA)’s Research Framework, the definition of Alzheimer's disease (AD) shifts from a syndromal to a biological entity, defined by underlying pathology as evidenced by the presence of AD biomarkers in vivo or on post-mortem examination (Jack et al., 2018, Alzheimers Dement. 2018 Apr;14(4):535-562). The new NIA-AA framework also describes syndromal staging of cognitive continuum to define research cohorts, independent of biomarker profile. With respect to mild cognitive impairment (MCI), the current framework differs from the 2011 NIA-AA definition in its reference to “neurobehavioral” symptoms, defined as symptoms attributable to mood or behavioral disorders, such as anxiety, depression, and apathy, which “commonly coexist and may be a prominent part of the presentation” (Table 3, Jack et al., 2018). We argue that neurobehavioural or neuropsychiatric symptoms (NPS) across the spectrum of AD disease should not be conceptualized as simply co-existing alongside cognitive impairment or attributable to mood or behavioural disorders. Rather, NPS are core features of neurodegenerative cognitive syndromes that may serve as prognostic indicators of outcome. This symposium will review the prevalence of NPS across the cognitive spectrum; namely in subjective cognitive decline (SCD), mild cognitive impairment (MCI), and Alzheimer's disease (AD), and highlight their association with AD biomarkers and contribution to future cognitive decline or disease progression in AD. Dr. Linda Mah will review the prevalence of neurobehavioural symptoms and their association with AD biomarkers and future cognitive decline in older adults who are cognitively unimpaired (CU) or who present with SCD, drawing from the extant literature and new data from an ongoing study of SCD. Dr. Krista L. Lanctôt will review the prevalence of NPS in mild neurocognitive disorder (NCD) and impact on progression. In addition, emerging evidence linking specific NPS with biomarkers of major NCD and the efficacy of interventions including pharmacologic, nonpharmacologic and neuromodulatory during this phase will be highlighted, with emphasis on recent findings. Dr. Corinne E. Fischer will review the prevalence and trajectory, clinical features and treatment approach to neuropsychiatric symptoms (NPS) in patients with established Alzheimer's disease. Particular emphasis will be placed on studies demonstrating the link between disease biomarkers and NPS disease burden, highlighting specific NPS such as apathy, aberrant sleep behavior, psychosis and depression.