title: Risk and protective factors for cognitive impairment in persons aged 85 years and older.
abstract: OBJECTIVE
  To determine risk and protective factors for mild cognitive impairment (MCI) among persons 85 years and older.
  
  
  METHODS
  Participants in the population-based prospective Mayo Clinic Study of Aging were comprehensively evaluated at baseline and at 15 monthly intervals to determine incident MCI. At baseline, lifestyle factors in midlife and late life were assessed by self-reported questionnaire; vascular and comorbid conditions were abstracted from participants' medical records.
  
  
  RESULTS
  Of 256 participants who were cognitively normal at enrollment (median age 87.3 years, 62% women), 121 developed MCI at a median 4.1 years of follow-up. Predictors of MCI were APOE ε4 allele (hazard ratio [HR] 1.89; p = 0.008), current depressive symptoms (HR 1.78; p = 0.02), midlife onset of hypertension (HR 2.43; p = 0.005), increasing number of vascular diseases (HR 1.13; p = 0.02), and chronic conditions from the Charlson Comorbidity Index (HR 1.08; p = 0.006). Models were adjusted for sex and education, with age as the time variable. The risk of MCI was reduced for participants who reported engagement in artistic (HR 0.27; p = 0.03), craft (HR 0.55; p = 0.02), and social (HR 0.45; p = 0.005) activities in both midlife and late life, and in the use of a computer in late life (HR 0.47; p = 0.008).
  
  
  CONCLUSIONS
  Chronic disease burden increases risk of MCI, whereas certain lifestyle factors reduce risk in persons 85 years and older. This implies that preventive strategies for MCI may need to begin in midlife and should persist throughout late life.
authors: From the Divisions of Epidemiology (R.O.R., M.M. Mielke, Y.E.G., R.C.P.) and Biomedical Statistics and Informatics (R.H.C.), Department of Health Sciences Research, the Department of Neurology (R.O.R., B.F.B., D.S.K., R.C.P.), and the Department of Psychiatry and Psychology (M.M. Machulda), Mayo Clinic, Rochester, MN; and the Departments of Psychiatry and Psychology and Neurology (Y.E.G.), Mayo Clinic, Scottsdale, AZ. roberts.rosebud@mayo.edu.
authors: Rosebud O
authors: RO
authors: Roberts
authors: From the Divisions of Epidemiology (R.O.R., M.M. Mielke, Y.E.G., R.C.P.) and Biomedical Statistics and Informatics (R.H.C.), Department of Health Sciences Research, the Department of Neurology (R.O.R., B.F.B., D.S.K., R.C.P.), and the Department of Psychiatry and Psychology (M.M. Machulda), Mayo Clinic, Rochester, MN; and the Departments of Psychiatry and Psychology and Neurology (Y.E.G.), Mayo Clinic, Scottsdale, AZ.
authors: Ruth H
authors: RH
authors: Cha
authors: From the Divisions of Epidemiology (R.O.R., M.M. Mielke, Y.E.G., R.C.P.) and Biomedical Statistics and Informatics (R.H.C.), Department of Health Sciences Research, the Department of Neurology (R.O.R., B.F.B., D.S.K., R.C.P.), and the Department of Psychiatry and Psychology (M.M. Machulda), Mayo Clinic, Rochester, MN; and the Departments of Psychiatry and Psychology and Neurology (Y.E.G.), Mayo Clinic, Scottsdale, AZ.
authors: Michelle M
authors: MM
authors: Mielke
authors: From the Divisions of Epidemiology (R.O.R., M.M. Mielke, Y.E.G., R.C.P.) and Biomedical Statistics and Informatics (R.H.C.), Department of Health Sciences Research, the Department of Neurology (R.O.R., B.F.B., D.S.K., R.C.P.), and the Department of Psychiatry and Psychology (M.M. Machulda), Mayo Clinic, Rochester, MN; and the Departments of Psychiatry and Psychology and Neurology (Y.E.G.), Mayo Clinic, Scottsdale, AZ.
authors: Yonas E
authors: YE
authors: Geda
authors: From the Divisions of Epidemiology (R.O.R., M.M. Mielke, Y.E.G., R.C.P.) and Biomedical Statistics and Informatics (R.H.C.), Department of Health Sciences Research, the Department of Neurology (R.O.R., B.F.B., D.S.K., R.C.P.), and the Department of Psychiatry and Psychology (M.M. Machulda), Mayo Clinic, Rochester, MN; and the Departments of Psychiatry and Psychology and Neurology (Y.E.G.), Mayo Clinic, Scottsdale, AZ.
authors: Bradley F
authors: BF
authors: Boeve
authors: From the Divisions of Epidemiology (R.O.R., M.M. Mielke, Y.E.G., R.C.P.) and Biomedical Statistics and Informatics (R.H.C.), Department of Health Sciences Research, the Department of Neurology (R.O.R., B.F.B., D.S.K., R.C.P.), and the Department of Psychiatry and Psychology (M.M. Machulda), Mayo Clinic, Rochester, MN; and the Departments of Psychiatry and Psychology and Neurology (Y.E.G.), Mayo Clinic, Scottsdale, AZ.
authors: Mary M
authors: MM
authors: Machulda
authors: From the Divisions of Epidemiology (R.O.R., M.M. Mielke, Y.E.G., R.C.P.) and Biomedical Statistics and Informatics (R.H.C.), Department of Health Sciences Research, the Department of Neurology (R.O.R., B.F.B., D.S.K., R.C.P.), and the Department of Psychiatry and Psychology (M.M. Machulda), Mayo Clinic, Rochester, MN; and the Departments of Psychiatry and Psychology and Neurology (Y.E.G.), Mayo Clinic, Scottsdale, AZ.
authors: David S
authors: DS
authors: Knopman
authors: From the Divisions of Epidemiology (R.O.R., M.M. Mielke, Y.E.G., R.C.P.) and Biomedical Statistics and Informatics (R.H.C.), Department of Health Sciences Research, the Department of Neurology (R.O.R., B.F.B., D.S.K., R.C.P.), and the Department of Psychiatry and Psychology (M.M. Machulda), Mayo Clinic, Rochester, MN; and the Departments of Psychiatry and Psychology and Neurology (Y.E.G.), Mayo Clinic, Scottsdale, AZ.
authors: Ronald C
authors: RC
authors: Petersen
mesh_terms: D000369:Aged, 80 and over; D053327:Apolipoprotein E4 / Q000235:genetics; D060825:Cognitive Dysfunction / Q000453:epidemiology* / Q000235:genetics; D015331:Cohort Studies; D015897:Comorbidity; D003863:Depression / Q000453:epidemiology*; D003924:Diabetes Mellitus, Type 2 / Q000453:epidemiology; D005260:Female; D020022:Genetic Predisposition to Disease; D006801:Humans; D006973:Hypertension / Q000453:epidemiology*; D008137:Longitudinal Studies; D008297:Male; D016016:Proportional Hazards Models; D011446:Prospective Studies; D065840:Protective Factors; D012307:Risk Factors; D014652:Vascular Diseases / Q000453:epidemiology*
chemical_list: D053327:Apolipoprotein E4