Alzheimer’s/Vascular Spectrum Dementia: Classification in Addition to Diagnosis

Article type: Research Article

Authors: Emrani, Sheina^a | Lamar, Melissa^b | Price, Catherine C.^c | Wasserman, Victor^a | Matusz, Emily^d | Au, Rhoda^e | Swenson, Rodney^f | Nagele, Robert^d | Heilman, Kenneth M.^g | Libon, David J.^{a; d; *}

Affiliations: [a] Department of Psychology, Rowan University, Glassboro, NJ, USA | [b] Department of Behavioral Sciences and the Rush Alzheimer’s Disease Center, Rush University Medical Center, Chicago, IL, USA | [c] Department of Clinical and Health Psychology, University of Florida, Gainesville, FL, USA | [d] New Jersey Institute for Successful Aging, School of Osteopathic Medicine, Rowan University, Glassboro, NJ, USA | [e] Department of Anatomy and Neurobiology, Neurology, Epidemiology, Boston University Schools of Medicine & Public Health, Boston, MA, USA | [f] Clinical Professor in the Department of Psychiatry and Behavioral Science at the University of North Dakota School of Medicine and Health Sciences, Grand Forks, ND, USA | [g] Department of Neurology, Brain Rehabilitation Research Center, Malcom Randall VA Medical Center, Center for Cognitive Aging and Memory – Clinical Translational Research Program, and Center for Neuropsychological Studies, University of Florida, Gainseville, FL, USA

Correspondence: [*] Correspondence to: David J. Libon, PhD, Rowan University, School of Osteopathic Medicine, New Jersey Institute for Successful Aging, Stratford, NJ 08084, USA. E-mail: libon@rowan.edu.

Abstract: Alzheimer’s disease (AD) and vascular dementia (VaD) are the two most common types of dementia. Although the combination of these disorders, called ‘mixed’ dementia, is recognized, the prevailing clinical and research perspective continues to consider AD and VaD as independent disorders. A review of recent neuropathological and neuropsychological literature reveals that these two disorders frequently co-occur and so-called ‘pure’ AD or VaD is comparatively rare. In addition, recent research shows that vascular dysfunction not only potentiates AD pathology, but that pathological changes in AD may subsequently induce vascular disorders. On the basis of these data, we propose that the neurobiological underpinnings underlying AD/VaD dementia and their neuropsychological phenotypes are best understood as existing along a clinical/pathological continuum or spectrum. We further propose that in conjunction with current diagnostic criteria, statistical modeling techniques using neuropsychological test performance should be leveraged to construct a system to classify AD/VaD spectrum dementia in order to test hypotheses regarding how mechanisms related to AD and VaD pathology interact and influence each other.

Keywords: Alzheimer’s disease, episodic memory, executive control, mixed dementia, vascular dementia

DOI: 10.3233/JAD-190654

Journal: Journal of Alzheimer's Disease, vol. 73, no. 1, pp. 63-71, 2020