title: Depression in mild cognitive impairment is associated with progression to Alzheimer's disease: a longitudinal study.
abstract: BACKGROUND
  Behavioral and psychological signs and symptoms of dementia (BPSD) belong to the core symptoms of dementia and are also common in mild cognitive impairment (MCI).
  
  
  OBJECTIVE
  This study would like to contribute to the understanding of the prognostic role of BPSD in MCI for the progression to dementia due to Alzheimer's disease (AD).
  
  
  METHODS
  Data were generated through an ongoing prospective longitudinal study on BPSD. Assessment was performed by means of the Middelheim Frontality Score, Behave-AD, Cohen-Mansfield Agitation Inventory, Cornell Scale for Depression in Dementia (CSDD), and Geriatric Depression Scale 30-questions (GDS-30). Cox proportional hazard models were used to test the hypothesis that certain BPSD in MCI are predictors of developing AD.
  
  
  RESULTS
  The study population consisted of 183 MCI patients at baseline. At follow-up, 74 patients were stable and 109 patients progressed to AD. The presence of significant depressive symptoms in MCI as measured by the CSDD (HR: 2.06; 95% CI: 1.23-3.44; p = 0.011) and the GDS-30 (HR: 1.77; 95% CI: 1.10-2.85; p = 0.025) were associated with progression to AD. The severity of depressive symptoms as measured by the GDS-30 was a predictor for progression too (HR: 1.06; 95% CI: 1.01-1.11; p = 0.020). Furthermore, the severity of agitated behavior, especially verbal agitation and the presence of purposeless activity, was also associated with progression, whereas diurnal rhythm disturbances were associated with no progression to AD.
  
  
  CONCLUSIONS
  Depressive symptoms in MCI appear to be predictors for progression to AD.
authors.affiliation: Reference Center for Biological Markers of Dementia (BIODEM), Laboratory of Neurochemistry and Behavior, Institute Born-Bunge, University of Antwerp, Antwerp, Belgium Department of Nursing and Midwifery Sciences, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium.
authors.forename: Stefan
authors.initials: S
authors.lastname: Van der Mussele
authors.affiliation: StatUa Center for Statistics, University of Antwerp, Antwerp, Belgium.
authors.forename: Erik
authors.initials: E
authors.lastname: Fransen
authors.affiliation: Reference Center for Biological Markers of Dementia (BIODEM), Laboratory of Neurochemistry and Behavior, Institute Born-Bunge, University of Antwerp, Antwerp, Belgium.
authors.forename: Hanne
authors.initials: H
authors.lastname: Struyfs
authors.affiliation: Reference Center for Biological Markers of Dementia (BIODEM), Laboratory of Neurochemistry and Behavior, Institute Born-Bunge, University of Antwerp, Antwerp, Belgium.
authors.forename: Jill
authors.initials: J
authors.lastname: Luyckx
authors.affiliation: Department of Neurology and Memory Clinic, Hospital Network Antwerp (ZNA), Middelheim and Hoge Beuken, Antwerp, Belgium Department of Clinical and Experimental Neurolinguistics (CLIN), Vrije Universiteit Brussel, Brussels, Belgium.
authors.forename: Peter
authors.initials: P
authors.lastname: Mariën
authors.affiliation: Department of Neurology and Memory Clinic, Hospital Network Antwerp (ZNA), Middelheim and Hoge Beuken, Antwerp, Belgium.
authors.forename: Jos
authors.initials: J
authors.lastname: Saerens
authors.affiliation: Department of Neurology and Memory Clinic, Hospital Network Antwerp (ZNA), Middelheim and Hoge Beuken, Antwerp, Belgium.
authors.forename: Nore
authors.initials: N
authors.lastname: Somers
authors.affiliation: Department of Neurology and Memory Clinic, Hospital Network Antwerp (ZNA), Middelheim and Hoge Beuken, Antwerp, Belgium.
authors.forename: Johan
authors.initials: J
authors.lastname: Goeman
authors.affiliation: Reference Center for Biological Markers of Dementia (BIODEM), Laboratory of Neurochemistry and Behavior, Institute Born-Bunge, University of Antwerp, Antwerp, Belgium Department of Neurology and Memory Clinic, Hospital Network Antwerp (ZNA), Middelheim and Hoge Beuken, Antwerp, Belgium Department of Rehabilitation Sciences and Physiotherapy, Faculty of Medicine and Health Sciences, University of Antwerp, Antwerp, Belgium Department of Neurology and Alzheimer Research Center, University Medical Center Groningen, University of Groningen, The Netherlands.
authors.forename: Peter P
authors.initials: PP
authors.lastname: De Deyn
authors.affiliation: Reference Center for Biological Markers of Dementia (BIODEM), Laboratory of Neurochemistry and Behavior, Institute Born-Bunge, University of Antwerp, Antwerp, Belgium Department of Neurology and Memory Clinic, Hospital Network Antwerp (ZNA), Middelheim and Hoge Beuken, Antwerp, Belgium.
authors.forename: Sebastiaan
authors.initials: S
authors.lastname: Engelborghs
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000175:diagnosis / Q000453:epidemiology / Q000523:psychology*; D060825:Cognitive Dysfunction / Q000175:diagnosis / Q000453:epidemiology / Q000523:psychology*; D003863:Depression; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D011379:Prognosis; D016016:Proportional Hazards Models; D011446:Prospective Studies; D011569:Psychiatric Status Rating Scales; D016019:Survival Analysis
keywords: Alzheimer's disease; BPSD; Cox proportional hazard; association; dementia; depression; depressive symptoms; mild cognitive impairment; predictor; prognostic value