COGNITIVE TRAJECTORIES IN PATIENTS WITH NON-AMNESTIC MILD COGNITIVE IMPAIRMENT: A LONGITUDINAL STUDY

Abstract

There are few studies that evaluate the clinical outcomes of patients with non-amnestic mild cognitive impairment (naMCI). The purpose of this study was to evaluate the cognitive trajectories in patients with naMCI and compared the baseline neuroimaging and neuropsychological features between fast and slow decliners. We recruited 121 patients who had been diagnosed as naMCI and had at least three years follow up. Worsening on the Clinical Dementia Rating sum of boxes (CDR-SOB) was defined as an outcome of clinical progression. Finite mixture modeling was employed to examine the quitting trajectories by the SAS Proc Traj group-based modeling procedure. Cortical thickness was measured using a surface-based method. We compared baseline cortical thickness, neuropsychological tests, and other risk factors between fast and slow decliners. A total 22 patients with naMCI progressed clinically (fast decliners), and 99 patients remained stable over 3 years (slow decliners). Compared to slow decliners, fast decliners were older. Fast decliners had lower raw scores on memory tasks, language impairment, and frontal/executive dysfunction at baseline neuropsychological tests, and more converted to dementia compared to slow decliners. In addition, fast decliners showed cortical thinning in the left dorsolateral prefrontal cortex and bilateral medial temporal lobes, compared to slow decliners.