title: Cognitive impairment in nondemented oldest-old: prevalence and relationship to cardiovascular risk factors.
abstract: OBJECTIVE
  To determine the prevalence and types of cognitive impairment in a sample of nondemented participants aged ≥90 (the oldest-old) and to examine the relationships between cognitive impairment and cardiovascular risk factors.
  
  
  METHODS
  The participants were 420 nondemented individuals from The 90+ Study, a study of aging and dementia in the oldest-old. These participants were categorized into four nonoverlapping groups: normal cognition, amnestic mild cognitive impairment (aMCI), nonamnestic MCI (naMCI), and other cognitive impairment (OCI). History of cardiovascular risk factors was assessed through self-report.
  
  
  RESULTS
  The overall prevalence of cognitive impairment in nondemented participants was 34.0% (95% CI: 29.5-38.5). The prevalence of OCI was highest (17.4%; 95% CI: 13.9-21.4), followed by aMCI (8.3%; 95% CI: 5.9-11.4) and naMCI (8.3%; 95% CI: 5.9-11.4). Normal cognition was present in 66.0% (95% CI: 61.2-70.5) of participants. History of hypertension and stroke were the only risk factors that varied between the groups, occurring more frequently in participants with naMCI (χ(2) = 3.82; P < .05) and OCI (χ(2) = 5.51; P < .05).
  
  
  CONCLUSIONS
  This study found a high prevalence of cognitive impairment in a sample of nondemented oldest-old. We did not find a strong relationship between cardiovascular risk factors and the cognitive impairment groups, other than between hypertension and naMCI and stroke and OCI. Future studies comparing the incidence of dementia in these groups will ultimately determine their predictive utility in the oldest-old.
authors: Institute for Memory Impairments and Neurological Disorders, University of California, Irvine, USA. cpeltz@uci.edu
authors: Carrie B
authors: CB
authors: Peltz
authors: María M
authors: MM
authors: Corrada
authors: Daniel J
authors: DJ
authors: Berlau
authors: Claudia H
authors: CH
authors: Kawas
mesh_terms: D000367:Age Factors; D000369:Aged, 80 and over; D000704:Analysis of Variance; D002318:Cardiovascular Diseases / Q000453:epidemiology*; D016009:Chi-Square Distribution; D003072:Cognition Disorders / Q000453:epidemiology*; D005260:Female; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests; D015995:Prevalence; D011569:Psychiatric Status Rating Scales; D012189:Retrospective Studies; D012307:Risk Factors; D012737:Sex Factors