title: Mild cognitive impairment, incidence, progression, and reversion: findings from a community-based cohort of elderly African Americans.
abstract: OBJECTIVE
  To examine the long-term outcomes of community-based elderly African Americans by following their transitions from normal cognition to mild cognitive impairment (MCI) to dementia.
  
  
  METHODS
  Participants were from the community-based Indianapolis Dementia Project. A total of 4,104 African Americans were enrolled in 1992 or 2001 and followed until 2009 with regularly scheduled evaluation of cognitive assessment. A two-stage sampling was used at each evaluation to select individuals for extensive clinical assessment following the results of Stage 1 cognitive testing. Age- and gender-specific incidence, progression, and reversion rates for MCI were derived using the person-year method in a dynamic cohort and predicted probabilities from weighted multinomial logistic models of transitional probabilities among normal cognition, MCI, and dementia.
  
  
  RESULTS
  Annual overall incidence rate for MCI was 5.6% (95% confidence interval [CI]: 4.6%-6.6%). Annual progression rate from MCI to dementia was 5.9% (95% CI: 5.3%-6.5%), and annual reversion rate from MCI to normal was 18.6% (95% CI: 16.7%-20.4%). Both MCI incidence rates and MCI to dementia progression rates increased with age, whereas reversion rates from MCI to normal decreased with age.
  
  
  CONCLUSIONS
  MCI progression to dementia was much more frequent in the older age groups than in younger participants where reversion to normal cognition is more common. Future research is needed to determine factors related to the heterogeneous outcomes in MCI individuals.
authors.affiliation: Department of Biostatistics, Indiana University School of Medicine, Indianapolis, IN. Electronic address: sgao@iupui.edu.
authors.forename: Sujuan
authors.initials: S
authors.lastname: Gao
authors.affiliation: Department of Psychiatry, Indiana University School of Medicine, Indianapolis, IN.
authors.forename: Frederick W
authors.initials: FW
authors.lastname: Unverzagt
authors.affiliation: Department of Psychiatry, Indiana University School of Medicine, Indianapolis, IN.
authors.forename: Kathleen S
authors.initials: KS
authors.lastname: Hall
authors.affiliation: Department of Biostatistics, Indiana University School of Medicine, Indianapolis, IN.
authors.forename: Kathleen A
authors.initials: KA
authors.lastname: Lane
authors.affiliation: Department of Pathology and Laboratory Medicine, Indiana University School of Medicine, Indianapolis, IN.
authors.forename: Jill R
authors.initials: JR
authors.lastname: Murrell
authors.affiliation: Department of Neurology, Indiana University School of Medicine, Indianapolis, IN; Department of Neurology, Indiana University, Indianapolis, IN.
authors.forename: Ann M
authors.initials: AM
authors.lastname: Hake
authors.affiliation: Department of Psychiatry, Indiana University School of Medicine, Indianapolis, IN; Richard L. Roudebush Veterans Administration Medical Center, Indianapolis, IN.
authors.forename: Valerie
authors.initials: V
authors.lastname: Smith-Gamble
authors.affiliation: Department of Psychiatry, Indiana University School of Medicine, Indianapolis, IN; Indiana University Center for Aging Research, Indianapolis, IN; Regenstrief Institute, Inc., Indianapolis, IN.
authors.forename: Hugh C
authors.initials: HC
authors.lastname: Hendrie
mesh_terms: D001741:Black or African American / Q000523:psychology*; D000368:Aged; D000369:Aged, 80 and over; D000375:Aging / Q000523:psychology*; D060825:Cognitive Dysfunction / Q000453:epidemiology* / Q000208:ethnology; D003704:Dementia / Q000453:epidemiology*; D018450:Disease Progression; D005260:Female; D006801:Humans; D015994:Incidence; D007196:Indiana / Q000453:epidemiology; D008297:Male; D009483:Neuropsychological Tests; D011446:Prospective Studies; D012075:Remission, Spontaneous; D012111:Residence Characteristics
keywords: African Americans; Mild cognitive impairment; dementia