title: Determining the association of the 5HTTLPR polymorphism with delusions and hallucinations in Lewy body dementias.
abstract: OBJECTIVE
  To determine whether the 5HTTLPR serotonin transporter polymorphism is associated with delusions and hallucinations in people with dementia with Lewy bodies (DLB) and Parkinson disease dementia (PDD).
  
  
  METHODS
  Prospective cohort study.
  
  
  METHODS
  A total of 187 individuals, recruited from centres in Norway, Sweden, and the United Kingdom were included in this study; 97 with clinically or neuropathologically diagnosed DLB/PDD and 90 cognitively normal individuals as a comparison group.
  
  
  METHODS
  All participants with dementia underwent serial evaluation of neuropsychiatric symptoms to assess the presence of persistent delusions and hallucinations using the Columbia University Scale for Psychopathology in Alzheimer disease, the Neuropsychiatric Inventory, or the Present Behavioural Examination. Severity of cognitive impairment was measured using the Mini Mental State Examination (MMSE). Individuals were genotyped for the 5HTTLPR polymorphism.
  
  
  RESULTS
  Logistic regression demonstrated that homozygosity for the L/L genotype and lower MMSE were associated with an increased risk for delusions (odds ratio: 11.5 and 1.16, respectively). Neither was significantly associated with hallucinations.
  
  
  CONCLUSIONS
  This study is the first to demonstrate the 5HTTLPR polymorphism is associated with delusions in Lewy body dementias, with important implications regarding the mechanisms underlying this symptom across the AD/DLB/PDD spectrum. Further studies are warranted to investigate this relationship further and examine treatment opportunities.
authors.affiliation: Wolfson Centre for Age-Related Diseases, King's College London, United Kingdom.
authors.forename: Byron
authors.initials: B
authors.lastname: Creese
authors.affiliation: Wolfson Centre for Age-Related Diseases, King's College London, United Kingdom.
authors.forename: Clive
authors.initials: C
authors.lastname: Ballard
authors.affiliation: Centre for Age-Related Medicine, Stavanger University Hospital, Stavanger, Norway; Department of Geriatric Medicine, Karolinska Institute, Stockholm, Sweden.
authors.forename: Dag
authors.initials: D
authors.lastname: Aarsland
authors.affiliation: Clinical Memory Research Unit, Department of Clinical Sciences Malmö, Lund University, Lund, Sweden.
authors.forename: Elisabet
authors.initials: E
authors.lastname: Londos
authors.affiliation: Mental Health Sciences Unit, University College London, United Kingdom.
authors.forename: Sally
authors.initials: S
authors.lastname: Sharp
authors.affiliation: Wolfson Centre for Age-Related Diseases, King's College London, United Kingdom. Electronic address: emma.3.jones@kcl.ac.uk.
authors.forename: Emma
authors.initials: E
authors.lastname: Jones
mesh_terms: D000368:Aged; D016022:Case-Control Studies; D003702:Delusions / Q000209:etiology / Q000235:genetics*; D005260:Female; D056726:Genetic Association Studies; D006212:Hallucinations / Q000209:etiology / Q000235:genetics*; D006801:Humans; D020961:Lewy Body Disease / Q000150:complications / Q000235:genetics* / Q000523:psychology; D008297:Male; D009483:Neuropsychological Tests; D011110:Polymorphism, Genetic / Q000235:genetics*; D011569:Psychiatric Status Rating Scales; D050486:Serotonin Plasma Membrane Transport Proteins / Q000235:genetics*
chemical_list: C493230:SLC6A4 protein, human; D050486:Serotonin Plasma Membrane Transport Proteins
keywords: 5HTTLPR; Parkinson disease dementia; SLC6A4; dementia with Lewy bodies; polymorphism; psychosis