title: Subjective cognitive impairment subjects in our clinical practice.
abstract: BACKGROUND
  The clinical challenge in subjective cognitive impairment (SCI) is to identify which individuals will present cognitive decline. We created a statistical model to determine which variables contribute to SCI and mild cognitive impairment (MCI) versus Alzheimer's disease (AD) diagnoses.
  
  
  METHODS
  A total of 993 subjects diagnosed at a memory clinic (2007-2009) were included retrospectively: 433 with SCI, 373 with MCI and 187 with AD. Descriptive statistics were provided. A logistic regression model analyzed the likelihood of SCI and MCI patients being diagnosed with AD, using age, gender, Mini-Mental State Examination score, the ratio of β-amyloid 42 divided by total tau, and phosphorylated tau as independent variables.
  
  
  RESULTS
  The SCI subjects were younger (57.8 ± 8 years) than the MCI (64.2 ± 10.6 years) and AD subjects (70.1 ± 9.7 years). They were more educated, had less medial temporal lobe atrophy (MTA) and frequently normal cerebrospinal fluid biomarkers. Apolipoprotein E4/E4 homozygotes and apolipoprotein E3/E4 heterozygotes were significantly less frequent in the SCI group (6 and 36%) than in the AD group (28 and 51%). Within the regression model, cardiovascular risk factors, confluent white matter lesions, MTA and central atrophy increased the AD likelihood for SCI subjects.
  
  
  CONCLUSIONS
  SCI patients form a distinct group. In our model, factors suggesting cardiovascular risk, MTA and central atrophy increased the AD likelihood for SCI subjects.
authors.affiliation: Division of Clinical Geriatrics, Department of Neurobiology, Care Sciences and Society, Sweden ; Department of Geriatric Medicine, Karolinska University Hospital, Sweden ; Department of Neurology, Hospital Clínico San Carlos, Ljubljana, Slovenia ; Department of Medicine, Universidad Complutense de Madrid, Madrid, Spain.
authors.forename: Sara
authors.initials: S
authors.lastname: Garcia-Ptacek
authors.affiliation: Department of Clinical Science, Intervention and Technology, Care Sciences and Society, Karolinska Institutet, Sweden ; Department of Radiology, Karolinska University Hospital, Stockholm, Sweden.
authors.forename: Lena
authors.initials: L
authors.lastname: Cavallin
authors.affiliation: Aging Research Center, Karolinska Institutet and Stockholm University, Sweden ; Institute for Gerontology, School of Health Sciences, Jönköping University, Jönköping, Sweden.
authors.forename: Ingemar
authors.initials: I
authors.lastname: Kåreholt
authors.affiliation: Karolinska Institutet Alzheimer Disease Research Center, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Sweden ; Department of Neurology, University Medical Centre, Ljubljana, Slovenia.
authors.forename: Milica Gregoric
authors.initials: MG
authors.lastname: Kramberger
authors.affiliation: Department of Neurology, University Medical Centre, Ljubljana, Slovenia.
authors.forename: Bengt
authors.initials: B
authors.lastname: Winblad
authors.affiliation: Division of Clinical Geriatrics, Department of Neurobiology, Care Sciences and Society, Sweden ; Department of Geriatric Medicine, Karolinska University Hospital, Sweden.
authors.forename: Vesna
authors.initials: V
authors.lastname: Jelic
authors.affiliation: Division of Clinical Geriatrics, Department of Neurobiology, Care Sciences and Society, Sweden ; Department of Geriatric Medicine, Karolinska University Hospital, Sweden.
authors.forename: Maria
authors.initials: M
authors.lastname: Eriksdotter
keywords: Alzheimer's disease; Dementia; Mild cognitive impairment