@article {7586, title = {Incidence of dementia and cognitive impairment, not dementia in the United States.}, journal = {Ann Neurol}, volume = {70}, year = {2011}, month = {2011 Sep}, pages = {418-26}, abstract = {

OBJECTIVE: Estimates of incident dementia, and cognitive impairment, not dementia (CIND) (or the related mild cognitive impairment) are important for public health and clinical care policy. In this paper, we report US national incidence rates for dementia and CIND.

METHODS: Participants in the Aging, Demographic, and Memory Study (ADAMS) were evaluated for cognitive impairment using a comprehensive in-home assessment. A total of 456 individuals aged 72 years and older, who were not demented at baseline, were followed longitudinally from August 2001 to December 2009. An expert consensus panel assigned a diagnosis of normal cognition, CIND, or dementia and its subtypes. Using a population-weighted sample, we estimated the incidence of dementia, Alzheimer disease (AD), vascular dementia (VaD), and CIND by age. We also estimated the incidence of progression from CIND to dementia.

RESULTS: The incidence of dementia was 33.3 (standard error [SE], 4.2) per 1,000 person-years and 22.9 (SE, 2.9) per 1,000 person-years for AD. The incidence of CIND was 60.4 (SE, 7.2) cases per 1,000 person-years. An estimated 120.3 (SE, 16.9) individuals per 1,000 person-years progressed from CIND to dementia. Over a 5.9-year period, about 3.4 million individuals aged 72 and older in the United States developed incident dementia, of whom approximately 2.3 million developed AD, and about 637,000 developed VaD. Over this same period, almost 4.8 million individuals developed incident CIND.

INTERPRETATION: The incidence of CIND is greater than the incidence of dementia, and those with CIND are at high risk of progressing to dementia, making CIND a potentially valuable target for treatments aimed at slowing cognitive decline.

}, keywords = {Aged, Aged, 80 and over, Alzheimer disease, Cognition Disorders, Cohort Studies, Dementia, Diagnostic and Statistical Manual of Mental Disorders, disease progression, Female, Humans, Logistic Models, Longitudinal Studies, Male, Models, Statistical, United States}, issn = {1531-8249}, doi = {10.1002/ana.22362}, author = {Brenda L Plassman and Kenneth M. Langa and Ryan J McCammon and Gwenith G Fisher and Guy G Potter and James R Burke and David C Steffens and Norman L Foster and Bruno J Giordani and Frederick W Unverzagt and Kathleen A Welsh-Bohmer and Steven G Heeringa and David R Weir and Robert B Wallace} } @article {7413, title = {Cognitive performance and informant reports in the diagnosis of cognitive impairment and dementia in African Americans and whites.}, journal = {Alzheimers Dement}, volume = {5}, year = {2009}, month = {2009 Nov}, pages = {445-53}, publisher = {5}, abstract = {

BACKGROUND: The diagnosis of cognitive impairment and dementia must reflect an increasingly diverse and aging United States population. This study compared direct testing and informant reports of cognition with clinical diagnoses of cognitive impairment and dementia between African Americans and whites.

METHODS: Participants in the Aging, Demographics, and Memory Study completed in-person dementia evaluations, and were assigned clinical diagnoses (by a consensus panel of dementia experts) of normal; cognitive impairment, not demented (CIND); and dementia. The Consortium to Establish a Registry for Alzheimer{\textquoteright}s Disease (CERAD) total score and the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE) were used to assess cognitive performance and reported cognitive decline.

RESULTS: A higher CERAD total score was associated with lower odds of CIND and dementia, at comparable ratios between African Americans and whites. Higher IQCODE scores were associated with increased odds of dementia in both African Americans and whites. Higher IQCODE scores were associated with increased odds of CIND among whites, but not among African Americans.

CONCLUSIONS: Cultural differences may influence informant reports of prevalent CIND and dementia. Our findings also highlight the need for more comparative research to establish the cultural validity of measures used to diagnose these conditions.

}, keywords = {Activities of Daily Living, Age of Onset, Aged, Aged, 80 and over, Black or African American, Caregivers, Cognition Disorders, Cohort Studies, Culture, Dementia, Disability Evaluation, Female, Geriatric Assessment, Health Surveys, Humans, Male, Neuropsychological tests, Observer Variation, Population Surveillance, Predictive Value of Tests, Prevalence, Psychiatric Status Rating Scales, Psychometrics, Registries, Sensitivity and Specificity, Surveys and Questionnaires, White People}, issn = {1552-5279}, doi = {10.1016/j.jalz.2009.04.1234}, author = {Guy G Potter and Brenda L Plassman and James R Burke and Mohammed U Kabeto and Kenneth M. Langa and David J Llewellyn and Mary A M Rogers and David C Steffens} } @article {7201, title = {Prevalence of cognitive impairment without dementia in the United States.}, journal = {Ann Intern Med}, volume = {148}, year = {2008}, month = {2008 Mar 18}, pages = {427-34}, publisher = {148}, abstract = {

BACKGROUND: Cognitive impairment without dementia is associated with increased risk for disability, increased health care costs, and progression to dementia. There are no population-based prevalence estimates of this condition in the United States.

OBJECTIVE: To estimate the prevalence of cognitive impairment without dementia in the United States and determine longitudinal cognitive and mortality outcomes.

DESIGN: Longitudinal study from July 2001 to March 2005.

SETTING: In-home assessment for cognitive impairment.

PARTICIPANTS: Participants in ADAMS (Aging, Demographics, and Memory Study) who were age 71 years or older drawn from the nationally representative HRS (Health and Retirement Study). Of 1770 selected individuals, 856 completed initial assessment, and of 241 selected individuals, 180 completed 16- to 18-month follow-up assessment.

MEASUREMENTS: Assessments, including neuropsychological testing, neurologic examination, and clinical and medical history, were used to assign a diagnosis of normal cognition, cognitive impairment without dementia, or dementia. National prevalence rates were estimated by using a population-weighted sample.

RESULTS: In 2002, an estimated 5.4 million people (22.2\%) in the United States age 71 years or older had cognitive impairment without dementia. Prominent subtypes included prodromal Alzheimer disease (8.2\%) and cerebrovascular disease (5.7\%). Among participants who completed follow-up assessments, 11.7\% with cognitive impairment without dementia progressed to dementia annually, whereas those with subtypes of prodromal Alzheimer disease and stroke progressed at annual rates of 17\% to 20\%. The annual death rate was 8\% among those with cognitive impairment without dementia and almost 15\% among those with cognitive impairment due to medical conditions.

LIMITATIONS: Only 56\% of the nondeceased target sample completed the initial assessment. Population sampling weights were derived to adjust for at least some of the potential bias due to nonresponse and attrition.

CONCLUSION: Cognitive impairment without dementia is more prevalent in the United States than dementia, and its subtypes vary in prevalence and outcomes.

}, keywords = {Aged, Aged, 80 and over, Cognition Disorders, Dementia, disease progression, Humans, Longitudinal Studies, Prevalence, United States}, issn = {1539-3704}, doi = {10.7326/0003-4819-148-6-200803180-00005}, author = {Brenda L Plassman and Kenneth M. Langa and Gwenith G Fisher and Steven G Heeringa and David R Weir and Mary Beth Ofstedal and James R Burke and Michael D Hurd and Guy G Potter and Willard L Rodgers and David C Steffens and John J McArdle and Robert J. Willis and Robert B Wallace} } @article {7164, title = {Prevalence of dementia in the United States: the aging, demographics, and memory study.}, journal = {Neuroepidemiology}, volume = {29}, year = {2007}, month = {2007}, pages = {125-32}, publisher = {29}, abstract = {

AIM: To estimate the prevalence of Alzheimer{\textquoteright}s disease (AD) and other dementias in the USA using a nationally representative sample.

METHODS: The Aging, Demographics, and Memory Study sample was composed of 856 individuals aged 71 years and older from the nationally representative Health and Retirement Study (HRS) who were evaluated for dementia using a comprehensive in-home assessment. An expert consensus panel used this information to assign a diagnosis of normal cognition, cognitive impairment but not demented, or dementia (and dementia subtype). Using sampling weights derived from the HRS, we estimated the national prevalence of dementia, AD and vascular dementia by age and gender.

RESULTS: The prevalence of dementia among individuals aged 71 and older was 13.9\%, comprising about 3.4 million individuals in the USA in 2002. The corresponding values for AD were 9.7\% and 2.4 million individuals. Dementia prevalence increased with age, from 5.0\% of those aged 71-79 years to 37.4\% of those aged 90 and older.

CONCLUSIONS: Dementia prevalence estimates from this first nationally representative population-based study of dementia in the USA to include subjects from all regions of the country can provide essential information for effective planning for the impending healthcare needs of the large and increasing number of individuals at risk for dementia as our population ages.

}, keywords = {Age Distribution, Aged, Aged, 80 and over, Cohort Studies, Dementia, Female, Geriatric Assessment, Health Surveys, Humans, Logistic Models, Male, Prevalence, Sex Distribution, United States}, issn = {1423-0208}, doi = {10.1159/000109998}, author = {Brenda L Plassman and Kenneth M. Langa and Gwenith G Fisher and Steven G Heeringa and David R Weir and Mary Beth Ofstedal and James R Burke and Michael D Hurd and Guy G Potter and Willard L Rodgers and David C Steffens and Robert J. Willis and Robert B Wallace} }