title: Association analysis of apolipoprotein E genotype and risk of depressive symptoms in Alzheimer's disease.
abstract: OBJECTIVE
  Behavioural and psychological symptoms of dementia (BPSD) are potent predictors of carer distress and admission to institutional care. In Alzheimer's disease (AD), depressive symptoms are one of the most common complaints affecting around 50% of all patients. There is speculation these symptoms result from known genetic risk factors for AD, therefore we investigated the role of apolipoprotein E epsilon4 in the aetiology of depression in AD.
  
  
  METHODS
  In this well-characterised cohort (n = 404) from the relatively genetically homogeneous Northern Ireland population, we tested the hypothesis that genetic variants of apolipoprotein E influence the risk for depressive symptoms in AD patients using the Neuropsychiatric Inventory (NPI-D) to determine the presence of depressive symptoms during the dementing illness.
  
  
  RESULTS
  A total of 55% of patients exhibited a history of depression/dysphoria during the course of the illness as gathered by the NPI-D questionnaire. Forty-six percent were suffering from depression/dysphoria when the analysis was restricted to the month prior to interview. No statistically significant association between genotypes or alleles of apolipoprotein E and depression/dysphoria in AD was observed, nor was any association noted between the presence of severe symptoms and genotypes/alleles of apolipoprotein E.
  
  
  CONCLUSIONS
  These results suggest apolipoprotein E genotype creates no additional risk for depressive symptoms in AD.
authors.affiliation: Department of Geriatric Medicine, Queen's University of Belfast, Belfast, Northern Ireland. david.craig@qub.ac.uk
authors.forename: David
authors.initials: D
authors.lastname: Craig
authors.forename: Dominic J
authors.initials: DJ
authors.lastname: Hart
authors.forename: Stephen P
authors.initials: SP
authors.lastname: McIlroy
authors.forename: A Peter
authors.initials: AP
authors.lastname: Passmore
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000175:diagnosis / Q000235:genetics* / Q000523:psychology; D053327:Apolipoprotein E4; D001057:Apolipoproteins E / Q000235:genetics*; D015331:Cohort Studies; D003863:Depression / Q000175:diagnosis / Q000235:genetics* / Q000523:psychology; D005260:Female; D005787:Gene Frequency / Q000235:genetics; D005838:Genotype; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests; D009660:Northern Ireland; D012306:Risk
chemical_list: D053327:Apolipoprotein E4; D001057:Apolipoproteins E