Longitudinal course and neuropathologic outcomes in original vs revised MCI and in pre-MCI

Objectives: To compare the natural history of individuals classified with mild cognitive impairment (MCI) in accordance with original criteria to the natural history of individuals classified with revised MCI criteria. Methods: The authors compared the rates of progression in 32 individuals with amnestic MCI and in 90 people with MCI according to revised criteria that allow nonamnestic deficits with progression in 276 individuals who were too minimally impaired (pre-MCI) to meet either MCI criteria. All individuals in this study were determined clinically to be very mildly cognitively impaired with a Clinical Dementia Rating (CDR) of 0.5. Results: Rates of progression for the two MCI groups were similar with a decline of almost 0.50 SD per year on a psychometric composite. Decline was less (0.23 SD) in the pre-MCI group. Median survival time to CDR 1 (mild dementia) was comparable for the original (95% CI: 3.79 to 4.07 years) and revised (95% CI: 3.29 to 5.40) criteria MCI groups but approximately twice as long in the pre-MCI group (95% CI: 6.72 to 8.93). All cases from the amnestic MCI criteria group with neuropathologic diagnoses met criteria for Alzheimer disease as did more than 90% in the other two groups. Conclusions: Mild cognitive impairment as originally and currently defined is usually early stage Alzheimer disease, which can begin with a cognitive deficit other than memory. It is possible to identify Alzheimer disease at an even earlier stage than mild cognitive impairment by focusing on intraindividual change rather than comparison with group norms.

[1]  S. DeKosky,et al.  Mild cognitive impairment, amnestic type , 2004, Neurology.

[2]  D. Wechsler Manual for the Wechsler Adult Intelligence Scale. , 1955 .

[3]  J. Morris,et al.  Neuropathologic Criteria for Diagnosing Alzheimer Disease in Persons with Pure Dementia of Alzheimer Type , 2004, Journal of neuropathology and experimental neurology.

[4]  J. Miller,et al.  A prospective study of cognitive function and onset of dementia in cognitively healthy elders. , 1998, Archives of neurology.

[5]  C. Jack,et al.  Mild cognitive impairment can be distinguished from Alzheimer disease and normal aging for clinical trials. , 2004, Archives of neurology.

[6]  J P Miller,et al.  The AD8 , 2005, Neurology.

[7]  L. Thal,et al.  Alzheimer's disease , 1986, Neurology.

[8]  D. Balota,et al.  Relating anatomy to function in Alzheimer's disease , 1998, Neurology.

[9]  J. Price,et al.  Mild cognitive impairment represents early-stage Alzheimer disease. , 2001, Archives of neurology.

[10]  J. Gustafsson,et al.  Estrogen Receptor-Beta Regulates Epithelial Cell Differentiation in the Mouse Ventral Prostate , 2004, Hormone Research in Paediatrics.

[11]  J. Morris,et al.  Current concepts in mild cognitive impairment. , 2001, Archives of neurology.

[12]  C. Jack,et al.  Mild cognitive impairment – beyond controversies, towards a consensus: report of the International Working Group on Mild Cognitive Impairment , 2004, Journal of internal medicine.

[13]  J. Ware,et al.  Random-effects models for longitudinal data. , 1982, Biometrics.

[14]  J. Morris,et al.  Clinical outcomes of possible versus probable Alzheimer’s disease , 2003, Neurology.

[15]  S. Folstein,et al.  "Mini-mental state". A practical method for grading the cognitive state of patients for the clinician. , 1975, Journal of psychiatric research.

[16]  M. Albert,et al.  Preclinical prediction of AD using neuropsychological tests , 2001, Journal of the International Neuropsychological Society.

[17]  J. Morris,et al.  Validation of clinical diagnostic criteria for Alzheimer's disease , 1988, Annals of neurology.

[18]  R D Hill,et al.  Very mild senile dementia of the Alzheimer type. II. Psychometric test performance. , 1989, Archives of neurology.

[19]  J Philip Miller,et al.  Rates of progression in mild cognitive impairment and early Alzheimer’s disease , 2002, Neurology.

[20]  K. Heilman,et al.  Relative Frequencies of Alzheimer Disease, Lewy Body, Vascular and Frontotemporal Dementia, and Hippocampal Sclerosis in the State of Florida Brain Bank , 2002, Alzheimer disease and associated disorders.

[21]  J. Baty,et al.  Mild senile dementia of the Alzheimer type. 4. Evaluation of intervention , 1992, Annals of neurology.

[22]  R. Katzman.,et al.  Validation of a short Orientation-Memory-Concentration Test of cognitive impairment. , 1983, The American journal of psychiatry.

[23]  D. Zaitchik,et al.  Predicting conversion to Alzheimer disease using standardized clinical information. , 2000, Archives of neurology.

[24]  D. Lanska The value of informant versus individual’s complaints of memory impairment in early dementia , 2001, Neurology.

[25]  John B. Shoven,et al.  I , Edinburgh Medical and Surgical Journal.

[26]  C. P. Hughes,et al.  A New Clinical Scale for the Staging of Dementia , 1982, British Journal of Psychiatry.

[27]  John Breitner,et al.  Prevalence and classification of mild cognitive impairment in the Cardiovascular Health Study Cognition Study: part 1. , 2003, Archives of neurology.

[28]  J. Price,et al.  Very mild Alzheimer's disease , 1991, Neurology.

[29]  Charles J Duffy,et al.  A visuospatial variant of mild cognitive impairment , 2003, Neurology.

[30]  J. Price,et al.  Clinicopathologic studies in cognitively healthy aging and Alzheimer's disease: relation of histologic markers to dementia severity, age, sex, and apolipoprotein E genotype. , 1998, Archives of neurology.

[31]  J. Morris The Clinical Dementia Rating (CDR) , 1993, Neurology.

[32]  Charles D. Smith,et al.  Neuropathologic substrate of mild cognitive impairment. , 2006, Archives of neurology.

[33]  H. Amièva,et al.  Annual Rate and Predictors of Conversion to Dementia in Subjects Presenting Mild Cognitive Impairment Criteria Defined according to a Population-Based Study , 2004, Dementia and Geriatric Cognitive Disorders.

[34]  D. Bennett,et al.  Vitamin E and donepezil for the treatment of mild cognitive impairment. , 2005, The New England journal of medicine.

[35]  E. Tangalos,et al.  Mild Cognitive Impairment Clinical Characterization and Outcome , 1999 .