title: Clustering of behavioural and psychological symptoms in dementia (BPSD): a European Alzheimer's disease consortium (EADC) study.
abstract: OBJECTIVE
  This cross-sectional study investigated the relationships between behavioural and psychological symptoms of dementia (BPSD).
  
  
  METHODS
  We recruited 194 patients with dementia from the memory clinic practice of six European Alzheimer's Disease Consortium centres. BPSD were assessed using a pre-designed questionnaire comprising the Neuropsychiatric Inventory (NPI). BPSD scores were analysed by Spearman's correlation analysis and principal components factor analysis. Results were confirmed by performing Varimax rotation of the factors.
  
  
  RESULTS
  The NPI symptoms occurred very frequently: 96% of the patients displayed at least one symptom. Among them, apathy (59.6%) and depression (58.5%) were the most common abnormalities, followed by irritability (44.6%), anxiety (44%) and agitation (41.5%). Four NPI-based factors were identified (58% of the common variance): psychosis factor (irritability, agitation, hallucinations and anxiety), psychomotor factor (aberrant motor behaviour and delusions), mood liability factor (disinhibition, elation and depression) and instinctual factor (appetite disturbance, sleep disturbance and apathy).
  
  
  CONCLUSIONS
  Psychosis, psychomotor factor, mood liability factor and instinctual factor form four distinct behavioural syndromes in dementia. We report the novel observation that depression clusters together with disinhibition and elation within a mood liability factor. This finding highlights the nature of mood, and mood oscillations, from depression to disinhibition within the cluster, and has implications for treatment by taking into consideration the poles of the mood scale and any oscillation between them.
authors: Department of Geriatrics and Gerontology, Ghent University Hospital and Heymans Institute of Pharmacology, Ghent, Belgium. mirko.petrovic@ugent.be
authors: M
authors: M
authors: Petrovic
authors: C
authors: C
authors: Hurt
authors: D
authors: D
authors: Collins
authors: A
authors: A
authors: Burns
authors: V
authors: V
authors: Camus
authors: R
authors: R
authors: Liperoti
authors: A
authors: A
authors: Marriott
authors: F
authors: F
authors: Nobili
authors: P
authors: P
authors: Robert
authors: M
authors: M
authors: Tsolaki
authors: B
authors: B
authors: Vellas
authors: F
authors: F
authors: Verhey
authors: E J
authors: EJ
authors: Byrne
mesh_terms: D000339:Affect; D000368:Aged; D000369:Aged, 80 and over; D016000:Cluster Analysis; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D003704:Dementia / Q000523:psychology*; D005060:Europe; D005260:Female; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests; D011597:Psychomotor Performance; D011618:Psychotic Disorders / Q000453:epidemiology*; D012720:Severity of Illness Index