@article {6822,
	title = {Empirically Derived Trajectories to Dementia Over 15 Years of Follow-up Identified by Using Mixed Membership Models.},
	journal = {Am J Epidemiol},
	volume = {182},
	year = {2015},
	month = {2015 Aug 15},
	pages = {366-74},
	abstract = {<p>Alzheimer disease is the most common form of dementia in the elderly, and the complex relationships among risk factors produce highly variable natural histories from normal cognition through the prodromal stage of mild cognitive impairment (MCI) to clinical dementia. We used a novel statistical approach, mixed membership trajectory models, to capture the variety of such pathways in 652 participants in the Cardiovascular Health Study Cognition Study over 22 years of follow-up (1992-2014). We identified 3 trajectories: a "healthy" profile with a peak probability of MCI between 95 and 100 years of age and only a 50\% probability of dementia by age 100; an "intermediate" profile with a peak probability of MCI between 85 and 90 years of age and progression to dementia between 90 and 95 years; and an "unhealthy" profile with a peak probability of progressing to MCI between ages 75 and 80 years and to dementia between the ages of 80 and 85 years. Hypertension, education, race, and the ϵ4 allele of the apolipoprotein E gene all affected the closeness of an individual to 1 or more of the canonical trajectories. These results provide new insights into the natural history of Alzheimer disease and evidence for a potential difference in the pathophysiology of the development of dementia.</p>},
	keywords = {Age Distribution, Aged, Aged, 80 and over, Alzheimer Disease, Apolipoprotein E4, Cardiovascular Diseases, Comorbidity, Dementia, Diabetes Mellitus, Disease Progression, Female, Follow-Up Studies, Humans, Magnetic Resonance Imaging, Male, Mild Cognitive Impairment, Neuroimaging, Prevalence, Proportional Hazards Models, Risk Factors, Sex Distribution},
	issn = {1476-6256},
	doi = {10.1093/aje/kwv051},
	author = {Lecci, Fabrizio and Junker, Brian and Kuller, Lewis H and Lopez, Oscar L and Becker, James T}
}
@article {6773,
	title = {Voxel Level Survival Analysis of Grey Matter Volume and Incident Mild Cognitive Impairment or Alzheimer{\textquoteright}s Disease.},
	journal = {J Alzheimers Dis},
	volume = {46},
	year = {2015},
	month = {2015},
	pages = {167-78},
	abstract = {<p>The purpose of this study was to identify, at the voxel level, brain regions associated with the time to develop mild cognitive impairment (MCI) or Alzheimer{\textquoteright}s disease (AD) from normal cognition. We analyzed incident MCI (n = 58) or AD (n = 151) in 292 cognitively normal participants in the Cardiovascular Health Study-Cognition Study (mean age = 79.2 {\textpm} 3.6 years). We used segmented, modulated grey matter maps from 3D (spoiled gradient echo) MRI scans obtained in 1998/99 (with clinical follow-up through 2012) that were smoothed with a 3-D 4 mm Gaussian filter. We fit approximately 1.92 million voxel-level Cox proportional hazard models to examine the grey matter volume effect on time to event, adjusting for age, sex, and diabetes. We used the significance threshold of p <  0.005 with contiguity threshold of at least 68 voxels (false detection probability <2.5{\texttimes}10 -8). Areas within the mesial temporal lobe (MTL), anterior temporal lobe, hippocampus, and posterior cingulate gyrus were associated with time to MCI or AD. The presence of white matter lesions (a marker of small vessel disease in the brain) was associated with the volumes of the MTL and precuneus; MRI-identified infarcts also predicted MTL volume. These findings are important because we identified critical brain regions that predict a person{\textquoteright}s increased likelihood of developing MCI or AD over a decade prior to the onset of clinical symptoms; these critical brain regions were themselves affected by the presence of vascular disease.</p>},
	keywords = {Aged, Aged, 80 and over, Alzheimer Disease, Chi-Square Distribution, Disease Progression, Female, Gray Matter, Humans, Incidence, Magnetic Resonance Imaging, Male, Mild Cognitive Impairment, Neuropsychological Tests, Psychiatric Status Rating Scales, Survival Analysis},
	issn = {1875-8908},
	doi = {10.3233/JAD-150047},
	author = {Zeifman, Lubov E and Eddy, William F and Lopez, Oscar L and Kuller, Lewis H and Raji, Cyrus and Thompson, Paul M and Becker, James T}
}
