Revisiting criteria for psychosis in Alzheimer’s disease and related dementias- towards better phenotypic classification and biomarker research

Abstract

Psychotic symptoms are common in Alzheimer’s disease (AD) and related neurodegenerative disorders and are associated with more rapid disease progression and increased mortality. It is unclear to what degree existing criteria are utilized in clinical research and practice. The International Society to Advance Alzheimer’s Research and Treatment (ISTAART) Neuropsychiatric Symptoms (NPS) Professional Interest Area (PIA) psychosis subgroup reviewed existing criteria for psychosis in AD and related dementias. Through a series of in person and on-line meetings, a priority checklist was devised to capture features necessary for current research and clinical needs. PubMed, Medline and other relevant databases were searched for relevant criteria. Consensus identified 3 sets of criteria suitable for review including those of Jeste and Finkel, Lyketsos, and the Diagnostic and Statistical Manual for Mental Disorders, 5th edition (DSM-5). It was concluded that existing criteria could be augmented by including a more specific differentiation between delusions and hallucinations, address overlap with related conditions (agitation in particular), adding the possibility of symptoms emerging in the preclinical and prodromal phases, and building on developing research in disease biomarkers. We propose criteria, developed to improve phenotypic classification of psychosis in AD, and advance the research agenda in the field to improve epidemiological, biomarker and genetics research in the field. These criteria serve as a complement to the IPA criteria for psychosis in neurocognitive disorders.