title: Synergistic associations of depression and apolipoprotein E genotype with incidence of dementia.
abstract: OBJECTIVE
  A cohort study of Japanese-American men suggested interactive effects of depression and apolipoprotein E (APOE) e4 allele on risk of incident dementia. In another sample of East Asian origin, we sought to replicate the findings and to explore individual depressive symptoms where this interaction was most evident.
  
  
  METHODS
  Of 625 Korean community elders without dementia at baseline, 518 (83%) were followed over a 2.4-year period and were clinically assessed for incident dementia. Depression was identified by the Geriatric Mental State Schedule (GMS), and nine individual depressive symptoms relevant to DSM-IV major depressive episode criteria were extracted. APOE genotype was ascertained. Covariates included age, gender, education, and disability.
  
  
  RESULTS
  There were synergistic interactions between depression and APOE e4 on incident dementia independent of covariates. This interaction was particularly strong for four depressive symptoms: depressed mood, worthlessness, concentration difficulty, and suicidal ideation.
  
  
  CONCLUSIONS
  We were able to replicate the previous study, finding that, at least in East Asian origin populations, the APOE e4 allele is a stronger predictor of incident dementia in the presence of depressive syndrome, and particular depressive symptoms.
authors.affiliation: Department of Psychiatry and Depression Clinical Research Centre, Chonnam National University Medical School, Kwangju, Republic of Korea.
authors.forename: Jae-Min
authors.initials: JM
authors.lastname: Kim
authors.forename: Robert
authors.initials: R
authors.lastname: Stewart
authors.forename: Seon-Young
authors.initials: SY
authors.lastname: Kim
authors.forename: Sung-Wan
authors.initials: SW
authors.lastname: Kim
authors.forename: Kyung-Yeol
authors.initials: KY
authors.lastname: Bae
authors.forename: Su-Jin
authors.initials: SJ
authors.lastname: Yang
authors.forename: Il-Seon
authors.initials: IS
authors.lastname: Shin
authors.forename: Jin-Sang
authors.initials: JS
authors.lastname: Yoon
mesh_terms: D000203:Activities of Daily Living; D000368:Aged; D053327:Apolipoprotein E4 / Q000235:genetics*; D044466:Asian People / Q000235:genetics; D003704:Dementia / Q000453:epidemiology* / Q000235:genetics* / Q000523:psychology; D003866:Depressive Disorder / Q000235:genetics*; D005260:Female; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D005838:Genotype; D006801:Humans; D015994:Incidence; D007723:Korea / Q000453:epidemiology; D008297:Male; D015999:Multivariate Analysis; D011446:Prospective Studies; D011569:Psychiatric Status Rating Scales
chemical_list: D053327:Apolipoprotein E4