[Clinical and neuropsychological criteria for the early determination of Mild Cognitive Impairment: a review and critical discussion].

Abstract

Since its introduction in 1999, the clinical syndrome Mild Cognitive Impairment (MCI) has been established in scientific and clinical practice. Technical and scientific advances made it necessary to regularly update research criteria, resulting in a shift to a more biological definition and biomarker-based criteria, while clinical core criteria remained essentially unchanged. The cognitive core criterion (objective evidence of cognitive impairment) allows concrete operationalization and has, in turn, led to the development of various neuropsychological criteria. Approaches more sensitive to early cognitive changes or taking greater account of cognitive decline may also be further elaborated for their future use. In general, certain conditions must be met for the use of neuropsychological criteria, such as the assessment of relevant cognitive domains with appropriately standardized test procedures to a sufficient extent. Standardized and consistent criteria use could reduce the high rates of variation observed in MCI prevalence rates and could help harmonizing prognostic evaluations and treatment decisions in routine clinical practice. Surveys of the status quo in German memory clinics suggest that there is a basis to possibly reach consensus on a set of criteria across institutions. Despite a potential commitment to specific neuropsychological criteria, clinical judgment appropriately considering individual factors would remain decisive for an MCI diagnosis and thus leaving existing MCI clinical core criteria untouched. The present work provides an overview on clinical and neuropsychological MCI criteria, discusses their challenges and future perspectives to timely and adequately detect first meaningful cognitive changes.