title: MRI-Based Classification Models in Prediction of Mild Cognitive Impairment and Dementia in Late-Life Depression.
abstract: Objective:Late-life depression (LLD) is associated with development of different types of dementia. Identification of LLD patients, who will develop cognitive decline, i.e., the early stage of dementia would help to implement interventions earlier. The purpose of this study was to assess whether structural brain magnetic resonance imaging (MRI) in LLD patients can predict mild cognitive impairment (MCI) or dementia 1 year prior to the diagnosis.Methods:LLD patients underwent brain MRI at baseline and repeated clinical assessment after 1-year. Structural brain measurements were obtained using Freesurfer software (v. 5.1) from the T1W brain MRI images. MRI-based Random Forest classifier was used to discriminate between LLD who developed MCI or dementia after 1-year follow-up and cognitively stable LLD. Additionally, a previously established Random Forest model trained on 185 patients with Alzheimer's disease (AD) vs. 225 cognitively normal elderly from the Alzheimer's disease Neuroimaging Initiative was tested on the LLD data set (ADNI model).Results:MCI and dementia diagnoses were predicted in LLD patients with 76%/68%/84% accuracy/sensitivity/specificity. Adding the baseline Mini-Mental State Examination (MMSE) scores to the models improved accuracy/sensitivity/specificity to 81%/75%/86%. The best model predicted MCI status alone using MRI and baseline MMSE scores with accuracy/sensitivity/specificity of 89%/85%/90%. The most important region for all the models was right ventral diencephalon, including hypothalamus. Its volume correlated negatively with the number of depressive episodes. ADNI model trained on AD vs. Controls using SV could predict MCI-DEM patients with 67% accuracy.Conclusion:LDD patients developing MCI and dementia can be discriminated from LLD patients remaining cognitively stable with good accuracy based on baseline structural MRI alone. Baseline MMSE score improves prediction accuracy. Ventral diencephalon, including the hypothalamus might play an important role in preservation of cognitive functions in LLD.
authors.affiliation: Department of Neurobiology, Care Sciences and Society, Karolinska Institutet Stockholm, Sweden.
authors.forename: Aleksandra K
authors.initials: AK
authors.lastname: Lebedeva
authors.affiliation: Department of Neurobiology, Care Sciences and Society, Karolinska Institutet Stockholm, Sweden.
authors.forename: Eric
authors.initials: E
authors.lastname: Westman
authors.affiliation: Centre for Old Age Psychiatric Research, Innlandet Hospital TrustBrumunddal, Norway; Institute of Clinical Medicine, Faculty of Medicine, University of OsloOslo, Norway.
authors.forename: Tom
authors.initials: T
authors.lastname: Borza
authors.affiliation: Department of Radiology and Nuclear Medicine, Oslo University Hospital, Rikshospitalet Oslo, Norway.
authors.forename: Mona K
authors.initials: MK
authors.lastname: Beyer
authors.affiliation: Department of Geriatric Medicine, Oslo University HospitalTønsberg, Norway; Oslo and Norwegian National Advisory Unit for Aging and HealthTønsberg, Norway.
authors.forename: Knut
authors.initials: K
authors.lastname: Engedal
authors.affiliation: Department of Neurobiology, Care Sciences and Society, Karolinska InstitutetStockholm, Sweden; Department of Old Age Psychiatry, Institute of Psychiatry, Psychology and Neuroscience, King's College LondonLondon, UK; Center for Age-Related Medicine, Stavanger University HospitalStavanger, Norway.
authors.forename: Dag
authors.initials: D
authors.lastname: Aarsland
authors.affiliation: Centre for Old Age Psychiatric Research, Innlandet Hospital TrustBrumunddal, Norway; Institute of Clinical Medicine, Faculty of Medicine, University of OsloOslo, Norway; Department of Geriatric Medicine, Oslo University HospitalTønsberg, Norway; Oslo and Norwegian National Advisory Unit for Aging and HealthTønsberg, Norway.
authors.forename: Geir
authors.initials: G
authors.lastname: Selbaek
authors.affiliation: Department of Neuroscience, Norwegian University of Science and TechnologyTrondheim, Norway; Department of Radiology and Nuclear Medicine, St. Olav's University HospitalTrondheim, Norway.
authors.forename: Asta K
authors.initials: AK
authors.lastname: Haberg
keywords: Alzheimer’s disease; Freesurfer; MCI; depression; depressive episodes; hypothalamus; neurodegeneration; ventral diencephalon