Trajectories of cognitive decline among patients with neurocognitive disorder: A seven-year retrospective cohort

BackgroundUnderstanding the progression of cognitive decline among subjects with neurocognitive disorders remains essential for current care in memory consultation.ObjectiveThe main objective of this study was to describe the evolution of cognitive decline in patients attending a memory clinic.MethodsA 7-year longitudinal retrospective study was conducted in the Nice Research Memory Centre using the neuropsychological assessment software developed in collaboration with the University CoBTeK team. Patients with two neuropsychological assessments diagnosing neurocognitive disorders related to the following etiologies were included: Alzheimer's disease (AD), vascular encephalopathy (VE with microvascular etiology and excluding stroke after-effect), or mixed neurocognitive disorder (Mx).Results791 patients were included in the analysis. Among them, the mean cognitive decline was around 1.5 points loss per year for the Mini-Mental State Examination (MMSE). There seemed to be a steeper annual cognitive decline when AD was involved in the pathological process (-2.0 ± 2.0 versus -0.7 ± 1.8 versus -1.6 ± 2.1 respectively for AD, VE, and Mx; p < 0.001). An early diagnosis at a minor stage of neurocognitive disorder, with a higher initial MMSE score and an isolated vascular encephalopathy, seemed associated with a slower cognitive decline.ConclusionsEtiological diagnosis and early entrance in the care pathway seemed closely related with cognitive evolution. This study seemed to identify a possible slower decline in a subgroup of patients with isolated microvascular encephalopathy. Further research is necessary to confirm this finding.