title: The effect of subsyndromal symptoms of depression and white matter lesions on disability for individuals with mild cognitive impairment.
abstract: OBJECTIVE
  To assess the effect of subsyndromal symptoms of depression (SSD) on ratings of disability for individuals with mild cognitive impairment (MCI).
  
  
  METHODS
  Data from 405 MCI participants from the Alzheimer's Disease Neuroimaging Initiative (ADNI) study were analyzed. Participants were evaluated at baseline and at 6-month intervals over 2 years. Severity of depressive symptoms was rated utilizing the Geriatric Depression Scale. Disability was assessed utilizing the Functional Assessment Questionnaire (FAQ). Other clinical variables included white matter lesion (WML) and intracranial brain (ICV) volumes derived from magnetic resonance imaging, ratings of overall cognitive function (Alzheimer's Disease Assessment Scale, ADAS), and apolipoprotein E (ApoE) status. Demographic variables included age, education, and gender.
  
  
  RESULTS
  SSD individuals had a lower volume of WML and higher frequency of ApoE ε4 alleles than nondepressed participants but the two groups did not differ with respect to other clinical or demographic variables. At baseline, SSD individuals were 1.77 times more likely to have poorer FAQ scores than individuals with no symptoms of depression after controlling for the effect of cognitive functioning, ICV, WML, and ApoE status. The presence of SSD at baseline was not associated with a poorer course of disability outcomes, cognitive functioning, or conversion to dementia over 24 months.
  
  
  CONCLUSIONS
  SSD demonstrated a significant impact on disability for MCI individuals, who are also at high risk for functional limitations related to neurodegenerative disease. Therefore, the treatment of SSD may represent a significant avenue to reduce the burden of disability in this vulnerable patient population.
authors.affiliation: Center for Imaging of Neurodegenerative Diseases, Veterans Administration Medical Center, San Francisco, CA; Department of Psychiatry, University of California, San Francisco, CA. Electronic address: scottm@lppi.ucsf.edu.
authors.forename: R Scott
authors.initials: RS
authors.lastname: Mackin
authors.forename: Philip
authors.initials: P
authors.lastname: Insel
authors.forename: Duygu
authors.initials: D
authors.lastname: Tosun
authors.forename: Susanne G
authors.initials: SG
authors.lastname: Mueller
authors.forename: Norbert
authors.initials: N
authors.lastname: Schuff
authors.forename: Diana
authors.initials: D
authors.lastname: Truran-Sacrey
authors.forename: Sky T
authors.initials: ST
authors.lastname: Raptentsetsang
authors.forename: Jun-Young
authors.initials: JY
authors.lastname: Lee
authors.forename: Clifford R
authors.initials: CR
authors.lastname: Jack
authors.forename: Paul S
authors.initials: PS
authors.lastname: Aisen
authors.forename: Ronald C
authors.initials: RC
authors.lastname: Petersen
authors.forename: Michael W
authors.initials: MW
authors.lastname: Weiner
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D053327:Apolipoprotein E4 / Q000235:genetics; D001921:Brain / Q000473:pathology; D060825:Cognitive Dysfunction / Q000235:genetics / Q000473:pathology / Q000523:psychology*; D003863:Depression / Q000235:genetics / Q000473:pathology / Q000523:psychology*; D004185:Disability Evaluation; D005260:Female; D005787:Gene Frequency; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009413:Nerve Fibers, Myelinated / Q000473:pathology; D009929:Organ Size; D012720:Severity of Illness Index
chemical_list: D053327:Apolipoprotein E4
keywords: ApoE; dementia; disability; longitudinal; mild cognitive impairment; subsyndromal depression; subthreshold depression; white matter lesions