Dag Aarsland

Karolinska Institutet, Сольна, Stockholm, Sweden

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Publications (387)2174.29 Total impact

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    ABSTRACT: Background: Mild cognitive impairment and dementia are common, clinically important features of Parkinson's disease (PD). The underlying disease pathology is heterogeneous and not yet well characterized. Biomarkers for cognitive impairment in PD could aid in diagnostic and prognostic evaluation and in the development of new cognitive enhancing treatments. Objective: To examine the relationship between CSF markers and cognition in a large, multicentre, cohort study of early, untreated PD, and compare marker concentrations between PD patients with and without MCI and healthy, age-matched controls. Methods: 414 early, untreated PD (34% with mild cognitive impairment) and 189 healthy, cognitively intact controls with baseline neuropsychological testing and CSF abeta42, t-tau, p-tau181 and α-synuclein results were included. Multiple linear regression models were constructed with a composite cognition factor, or memory-, or visuospatial- or executive-attention domains as dependent variables, and CSF markers, demographic characteristics and MDS-UPDRS III score as predictors. Results: Lower α-synuclein was associated with reduced performance on the executive-attention domain and the composite cognition factor in the whole PD-group. Abeta42 was significantly decreased in PD with mild cognitive impairment compared with controls after adjusting for covariates, while values in PD without MCI were identical to healthy controls. Conclusions: The association between reduced CSF α-synuclein concentrations and cognition suggests that α-synuclein pathology contributes to early cognitive impairment in PD, in particular to executive-attentional dysfunction. Longitudinal analyses are needed to determine if this and other CSF biomarkers in early Parkinson's disease are associated with the risk of future cognitive decline and dementia.
    11/2015; DOI:10.3233/JPD-150682
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    ABSTRACT: Background: Sleep disturbances (SDs) are common in patients with all forms of dementia. However, most studies focus on Alzheimer's disease (AD) and less is known about the prevalence and characteristics of SD in dementia with Lewy bodies (DLB). Objective: The aims of this cross-sectional study were: (1) to examine the frequency of SD in DLB versus AD; (2) to compare patients with and without SD with regard to relevant clinical variables, and (3) to investigate the associations between SD and medication use. Methods: Patients with a first-time diagnosis of probable or possible DLB or AD were selected from the Dementia Study of Western Norway and recruited from clinics for old age psychiatry from 2010 until the end of 2013. Results: In all, 123 (55.7%) subjects with dementia suffered from at least one SD. Insomnia was present in 77 (34.8%), and 34 (20.7%) patients had probable REM-sleep behaviour disorder (RBD). All SDs were also significantly more frequent in patients with DLB than in AD, and DLB patients also more often had several co-occurring SDs. The presence of any SD was associated with more neuropsychiatric symptoms, higher morbidity, more parkinsonian symptoms and excessive daytime sleepiness. Antiparkinsonian medication was used more often in RBD, restless leg syndrome (RLS) and periodic limb movements, and benzodiazepines were also common in RLS. Conclusions: Sleep problems are more common in DLB patients compared to AD, and are associated with more clinical impairment. DLB patients frequently have several sleep problems occurring simultaneously, which suggests a need for screening and accurate assessment of sleep in DLB.
    Neurodegenerative Diseases 11/2015; DOI:10.1159/000439252 · 3.51 Impact Factor
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    ABSTRACT: Cerebrospinal fluid (CSF) has been extensively studied to explore biochemical alterations in subjects with neurodegenerative disorders. In Alzheimer's disease (AD), levels of increased CSF tau protein and decreased levels of β-amyloid 1-42 (Aβ42) have been shown to correlate with brain plaque formation and tangle pathology. Intracellular Lewy inclusions containing aggregated α-synuclein (α-syn) represent a pathological hallmark of Parkinson's disease (PD). In most-but not all-studies published to date total CSF α-syn concentrations have been found to be decreased in disorders related to α-syn pathology, i.e., PD, dementia with Lewy-bodies and multiple system atrophy. However, these reports show extensive signal overlap among tested individuals, thereby diminishing its potential for routine use in clinical practice. To investigate potential biological (i.e., non-technical) confounders of reported CSF levels for α-syn, Aβ42 and tau in PD and related disorders, we carried out a methodical review of known factors that underlie signal variability and speculate on those that have not yet been tested. We discuss several biological factors, such as neuropathology, demographics, clinical phenotype, progression and duration of disease, concomitant illnesses and, last but not least, pharmacotherapy, which in isolation or combination can substantially alter values for CSF proteins of interest. Enhanced implementation of standardized clinical protocols, streamlined operating procedures, and further progress in the development of validated assays for CSF proteins have the potential to (1) inform us as to the pathogenesis of disease, (2) support the laboratory-based diagnosis for symptomatic subjects in the future, and (3) facilitate breakthrough therapies to alter the course of neurodegenerative disorders, such as PD and AD. This article is protected by copyright. All rights reserved.
    Journal of Neurochemistry 10/2015; DOI:10.1111/jnc.13390 · 4.28 Impact Factor

  • The Lancet 10/2015; 386(10004):1683-1697. DOI:10.1016/S0140-6736(15)00462-6 · 45.22 Impact Factor
  • Dag Aarsland ·
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    ABSTRACT: Parkinson's disease (PD) and dementia with Lewy bodies (DLB) share clinical and pathological similarities. The defining features are motor parkinsonism and cognitive impairment, often accompanied by visual hallucinations, fluctuating consciousness, autonomic and sleep disturbances, and a number of other non-motor symptoms. Mild cognitive impairment (MCI) can be identified in 15% of PD patients at time of diagnosis, and may even precede motor symptoms. MCI usually progresses further, and dementia is a common endpoint. Cognitive impairment is usually the initial symptom of DLB, and the disease course is severe. A variety of biomarkers can assist in the diagnosis and prognosis of PD and DLB, including structural and functional imaging, cerebrospinal fluid, and EEG. Compared to the many treatments available for motor symptoms, relatively few systematic studies exist to guide the treatment of cognitive impairment in PD, and even less in DLB. However, there is good evidence for cholinesterase inhibitors in both DLB and PD with dementia, and some indications that memantine is helpful. Emerging evidence suggest that physical exercise and cognitive training are also effective, as are some reports of various brain stimulation techniques. Disease-modifying agents that delay the rate of cognitive decline in PD and DLB are urgently needed.
    Parkinsonism & Related Disorders 09/2015; 22 Suppl 1. DOI:10.1016/j.parkreldis.2015.09.034 · 3.97 Impact Factor
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    ABSTRACT: Background: Autoantibodies with agonist function are described in cardiovascular disorders. Since vascular risk factors are associated with an increased risk for Alzheimer's disease (AD), we investigated a potential association between antibodies to the angiotensin 2 type 1 receptor (anti-AT1R) and AD. Objective: The primary objective of this study was to investigate the association between anti-AT1R and AD. The secondary objective was to investigate the association between clinical or biomarker features of AD and anti-AT1R. Methods: Samples from patients with mild AD participating in a longitudinal study in Western Norway (n = 92, 65 [71%] females, mean age 74.8 [range 50-89]) and age- and gender-matched healthy controls (n = 102) were included. Cerebrospinal fluid (CSF) AD biomarkers were assessed in a subgroup of patients. Patients were examined annually, including Mini-Mental State Examination. ELISA was used to measure anti-AT1R in serum. Non-parametric tests were used for statistical calculations and a p < 0.05 was considered significant. Results: AD patients had significantly higher levels of anti-AT1R compared with healthy controls (10.2 U/mL versus 8.1 U/mL, p = 0.04). This difference was found only in patients without hypertension and diabetes. Anti-AT1R levels correlated with CSF total tau (p = 0.03) and phosphorylated tau (p = 0.03) levels, and inversely with blood pressure in AD (Spearman R -0.277, p = 0.008). Discussion: AD is associated with increased levels of anti-AT1R, and the antibodies correlated with CSF total, and phosphorylated tau levels. Further research is needed to understand the blood pressure response in AD without hypertension and a potential link between tau and anti-AT1R in AD.
    Journal of Alzheimer's disease: JAD 09/2015; 47(2):523-529. DOI:10.3233/JAD-150053 · 4.15 Impact Factor
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    ABSTRACT: Background: Nursing home patients have complex mental and physical health problems, disabilities and social needs, combined with widespread prescription of psychotropic drugs. Preservation of their quality of life is an important goal. This can only be achieved within nursing homes that offer competent clinical conditions of treatment and care. COmmunication, Systematic assessment and treatment of pain, Medication review, Occupational therapy, Safety (COSMOS) is an effectiveness-implementation hybrid trial that combines and implements organization of activities evidence-based interventions to improve staff competence and thereby the patients' quality of life, mental health and safety. The aim of this paper is to describe the development, content and implementation process of the COSMOS trial. Methods/design: COSMOS includes a 2-month pilot study with 128 participants distributed among nine Norwegian nursing homes, and a 4-month multicenter, cluster randomized effectiveness-implementation clinical hybrid trial with follow-up at month 9, including 571 patients from 67 nursing home units (one unit defined as one cluster). Clusters are randomized to COSMOS intervention or current best practice (control group). The intervention group will receive a 2-day education program including written guidelines, repeated theoretical and practical training (credited education of caregivers, physicians and nursing home managers), case discussions and role play. The 1-day midway evaluation, information and interviews of nursing staff and a telephone hotline all support the implementation process. Outcome measures include quality of life in late-stage dementia, neuropsychiatric symptoms, activities of daily living, pain, depression, sleep, medication, cost-utility analysis, hospital admission and mortality. Discussion: Despite complex medical and psychosocial challenges, nursing home patients are often treated by staff possessing low level skills, lacking education and in facilities with a high staff turnover. Implementation of a research-based multicomponent intervention may improve staff's knowledge and competence and consequently the quality of life of nursing home patients in general and people with dementia in particular. Trial registration: ClinicalTrials.gov NCT02238652.
    Implementation Science 09/2015; 10(1):131. DOI:10.1186/s13012-015-0310-5 · 4.12 Impact Factor
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    Dag Aarsland · Milica Gregoric Kramberger ·
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    ABSTRACT: Parkinson's disease (PD) is characterized by motor symptoms, but focused and extensive research in the last years has provided new knowledge in the field of non-motor symptoms. Non-motor symptoms include neuropsychiatric symptoms such as depression, anxiety, psychosis, apathy, impulse control disorders, and occur in the majority of patients with PD. They are associated with impaired quality of life for patients and relatives, additional deterioration of function and increased use of health resources. Medical and surgical therapies commonly used for treatment of PD can induce or worsen such symptoms. This paper discusses the epidemiology, clinical features and treatment approaches for neuropsychiatric symptoms (NPS) in PD in the perspective of clinical practice and management. The prevalence rates of various NPS are high, various demographic, clinical and treatment related variables have shown to be associated with higher risk of NPS. Randomized controlled trials of pharmacological and non-pharmacological treatments of NPS in PD are sparse. Current evidence supports tricyclic antidepressants as efficacious treatment of depression in PD and antipsychotic clozapine as efficacious choice for psychosis. Further studies to evaluate various other management strategies of NPS in PD are required. Neuropsychiatric symptoms in PD should be considered an integral part of the disease; hence a multidisciplinary approach is essential to improve the overall outcome of PD also through raised awareness and enriched knowledge on NPS.
    Journal of Parkinson's Disease 09/2015; 5(3):659-667. DOI:10.3233/JPD-150604 · 1.91 Impact Factor
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    ABSTRACT: We compared cortical thickness between patients with late-life depression (LLD) and healthy controls and between patients with early-onset (EOD) and late-onset (LOD) depression. We also tested age effects on cortical thickness in LLD and controls and if cortical thickness and hippocampal volumes were associated with cognitive performance in LLD. Three-dimensional T1-weighted magnetic resonance images were obtained in 49 LLD and 49 matched hospital controls and processed using FreeSurfer. General linear model analysis was used as a statistical approach. LLD group had thinning in the left parahippocampal, fusiform, and inferior-parietal cortex compared with controls. Age correlated with cortical thinning in controls but not in LLD. Women in the LOD groups had extensive cortical thinning in the lateral prefrontal cortex bilaterally compared with EOD women. Absence of statistically significant changes observed in men should however be treated with caution because of the low number of men in the study. Mini-Mental Status Examination score correlated with lateral prefrontal cortical thickness bilaterally and hippocampal volume in the total group of LLD and in LOD but not EOD. LLD is associated with cortical thinning, which is associated with age at depression onset, gender, and level of cognitive functioning. Copyright © 2015 Elsevier Inc. All rights reserved.
    Neurobiology of aging 08/2015; DOI:10.1016/j.neurobiolaging.2015.04.020 · 5.01 Impact Factor
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    DESCRIPTION: Admitted to peer-review in Neurodegenerative Diseases
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  • Inger van Steenoven · Dag Aarsland · Daniel Weintraub ·

    Movement Disorders 07/2015; DOI:10.1002/mds.26367 · 5.68 Impact Factor
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    ABSTRACT: Little is known about the underlying mechanisms of clinical symptoms in dementia with Lewy bodies. The aim of this study was to explore the association between loss of striatal dopamine transporter binding and symptoms in dementia with Lewy bodies. Thirty-five patients with dementia with Lewy bodies underwent single-photon emission computerized tomography brain imaging with N-ω-fluoropropyl-2β-carbomethoxy-3β-(4-iodophenyl)nortropane ([(123) I]FP-CIT). Associations between striatal binding ratios and motor (UPDRS), psychiatric (Neuropsychiatric Inventory; [NPI]), and cognitive (Mini-Mental State Examination [MMSE] and neuropsychological tests) symptoms were assessed by linear regression analysis. The explorative analysis showed that the motor UPDRS was negatively associated with putamen dopamine transporter binding, whereas no association with striatal dopamine transporter binding was found for total NPI, hallucinations, apathy, depression, anxiety, and MMSE scores. However, in post-hoc analysis, executive impairment was positively associated with dopamine transporter loss after adjustment of age and gender. Dopamine deficiency in patients with dementia with Lewy bodies was associated with severity of motor symptoms, but did not correlate significantly with ratings of neurobehavioral disturbances or overall cognition. © 2015 International Parkinson and Movement Disorder Society. © 2015 International Parkinson and Movement Disorder Society.
    Movement Disorders 07/2015; DOI:10.1002/mds.26327 · 5.68 Impact Factor
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    ABSTRACT: The unfolded protein response (UPR) is a pro-survival defense mechanism induced during periods of endoplasmic reticulum stress, and it has recently emerged as an attractive therapeutic target across a number of neurodegenerative conditions, but has not yet been studied in synuclein disorders. The level of a key mediator of the UPR pathway, glucose regulated protein 78 (GRP78), also known as binding immunoglobulin protein (BiP), was measured in post-mortem brain tissue of patients with dementia with Lewy bodies (DLB) and Parkinson's disease dementia (PDD) in comparison to Alzheimer's disease (AD) and age matched controls using western blot. The UPR activation was further confirmed by immunohistochemical detection of GRP78/BiP and phosphorylated protein kinase RNA-like ER kinase (p-PERK). GRP78/BiP was increased to a greater extent in DLB and PDD patients compared to AD and control subjects in cingulate gyrus and parietal cortex. However, there were no changes in the prefrontal and temporal cortices. There was a significant positive correlation between GRP78/BiP level and α-synuclein pathology in the cingulate gyrus, while AD-type pathology showed an inverse correlation relationship in the parietal cortex. Overall, these results give emphasis to the role of UPR in Lewy body dementias, and suggest that Lewy body degeneration, in combination with AD-type pathologies, is associated with increased UPR activation to a greater extent than AD alone, possibly as a consequence of the increasing load of ER proteins. This work also highlights a novel opportunity to explore the UPR as a therapeutic target in synuclein diseases. This article is protected by copyright. All rights reserved.
    Neuropathology and Applied Neurobiology 07/2015; DOI:10.1111/nan.12260 · 3.93 Impact Factor
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    ABSTRACT: Cerebral amyloid-β aggregation is an early pathological event in Alzheimer disease (AD), starting decades before dementia onset. Estimates of the prevalence of amyloid pathology in persons without dementia are needed to understand the development of AD and to design prevention studies. To use individual participant data meta-analysis to estimate the prevalence of amyloid pathology as measured with biomarkers in participants with normal cognition, subjective cognitive impairment (SCI), or mild cognitive impairment (MCI). Relevant biomarker studies identified by searching studies published before April 2015 using the MEDLINE and Web of Science databases and through personal communication with investigators. Studies were included if they provided individual participant data for participants without dementia and used an a priori defined cutoff for amyloid positivity. Individual records were provided for 2914 participants with normal cognition, 697 with SCI, and 3972 with MCI aged 18 to 100 years from 55 studies. Prevalence of amyloid pathology on positron emission tomography or in cerebrospinal fluid according to AD risk factors (age, apolipoprotein E [APOE] genotype, sex, and education) estimated by generalized estimating equations. The prevalence of amyloid pathology increased from age 50 to 90 years from 10% (95% CI, 8%-13%) to 44% (95% CI, 37%-51%) among participants with normal cognition; from 12% (95% CI, 8%-18%) to 43% (95% CI, 32%-55%) among patients with SCI; and from 27% (95% CI, 23%-32%) to 71% (95% CI, 66%-76%) among patients with MCI. APOE-ε4 carriers had 2 to 3 times higher prevalence estimates than noncarriers. The age at which 15% of the participants with normal cognition were amyloid positive was approximately 40 years for APOE ε4ε4 carriers, 50 years for ε2ε4 carriers, 55 years for ε3ε4 carriers, 65 years for ε3ε3 carriers, and 95 years for ε2ε3 carriers. Amyloid positivity was more common in highly educated participants but not associated with sex or biomarker modality. Among persons without dementia, the prevalence of cerebral amyloid pathology as determined by positron emission tomography or cerebrospinal fluid findings was associated with age, APOE genotype, and presence of cognitive impairment. These findings suggest a 20- to 30-year interval between first development of amyloid positivity and onset of dementia.
    JAMA The Journal of the American Medical Association 05/2015; 313(9):1924-1938. DOI:10.1001/jama.2015.4668 · 35.29 Impact Factor
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    ABSTRACT: The aim of this study was to assess whether mild cognitive impairment (MCI) is associated with disruption in large-scale structural networks in newly diagnosed, drug-naïve patients with Parkinson's disease (PD). Graph theoretical analyses were applied to 3T MRI data from 123 PD patients and 56 controls from the Parkinson's progression markers initiative (PPMI). Thirty-three patients were classified as having Parkinson's disease with mild cognitive impairment (PD-MCI) using the Movement Disorders Society Task Force criteria, while the remaining 90 PD patients were classified as cognitively normal (PD-CN). Global measures (clustering coefficient, characteristic path length, global efficiency, small-worldness) and regional measures (regional clustering coefficient, regional efficiency, hubs) were assessed in the structural networks that were constructed based on cortical thickness and subcortical volume data. PD-MCI patients showed a marked reduction in the average correlation strength between cortical and subcortical regions compared with controls. These patients had a larger characteristic path length and reduced global efficiency in addition to a lower regional efficiency in frontal and parietal regions compared with PD-CN patients and controls. A reorganization of the highly connected regions in the network was observed in both groups of patients. This study shows that the earliest stages of cognitive decline in PD are associated with a disruption in the large-scale coordination of the brain network and with a decrease of the efficiency of parallel information processing. These changes are likely to signal further cognitive decline and provide support to the role of aberrant network topology in cognitive impairment in patients with early PD. Hum Brain Mapp, 2015. © 2015 Wiley Periodicals, Inc. © 2015 Wiley Periodicals, Inc.
    Human Brain Mapping 05/2015; 36(8). DOI:10.1002/hbm.22822 · 5.97 Impact Factor
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    ABSTRACT: Cognitive impairment in early Parkinson's disease (PD) is common and distinct from early Alzheimer's disease. Predictors and mechanisms are only partially known, but α-synuclein, amyloid-β and tau dysmetabolism may be involved. Our aim was to study associations between cerebrospinal fluid biomarkers (CSF) and cognition in non-dementia PD compared to normal controls (NC) and non-PD patients with mild cognitive impairment (MCI non-PD). Patients were classified as having normal, subjective or mild cognitive impairment after cognitive screening. CSF levels of total α-synuclein (t-α-syn), amyloid-β (Aβ) 38, 40 and 42, total tau (T-tau) and phosphorylated tau (P-tau) were measured in 34 NC, 31 early, non-dementia PD and 28 MCI non-PD patients. A well validated neuropsychological test battery was administered. In the PD group, 13 had normal cognition, 4 had subjective and 14 mild cognitive impairment. PD patients had significantly lower CSF biomarker levels of t-α-syn, Aβ38, 40 and 42, T-tau and P-tau compared to NC. Compared to MCI non-PD, t-α-syn, Aβ38 and 40, T-tau and P-tau were also lower, while Aβ42 was significantly higher in the PD group. Aβ38 and 40 correlated strongly with t-α-syn levels in PD. Lower Aβ42 was associated with decreased verbal learning, delayed verbal recall and response inhibition in PD. While Aβ38, 40 and t-α-syn levels are strongly correlated, only lower Aβ42 was associated with reduced cognitive functions in early PD, mainly connected to medial temporal lobe-based cognitive functions. Copyright © 2015 Elsevier Ltd. All rights reserved.
    Parkinsonism & Related Disorders 05/2015; 21(7). DOI:10.1016/j.parkreldis.2015.04.027 · 3.97 Impact Factor
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    ABSTRACT: The specific profile of dementia in Parkinson's disease (PDD) and dementia with Lewy bodies (DLB) in the earliest stages of dementia is still unclear and subject of considerable controversy. We investigated 27 PDD patients and 24 DLB patients with parkinsonism in the early stage of dementia, i.e. with a Mini-Mental State Examination score of ≥24. Compared to PDD, patients with DLB demonstrated significantly lower scores when testing attention and executive functions [modified card sorting test (p < 0.001) and digit span backward (p < 0.02)], as well as when testing constructive abilities [copy of complex designs (p = 0.001) and pentagon (p < 0.001)]. Using logistic regression analysis, diagnosis was predicted from the cognitive profile, with an overall accuracy of 88.2%. In addition, PDD patients showed a significantly higher Unified Parkinson's Disease Rating Scale (UPDRS) motor subscore (p < 0.001) as well as higher UPDRS motor item scores [tremor at rest (p = 0.01) and bradykinesia (p = 0.001)]. The cognitive profile in PDD differs from that in DLB in the early stage of dementia, with worse performance on tests of attention and executive functions and constructive abilities in DLB compared to PDD patients. In contrast, motor symptoms are more severe in PDD than in DLB.
    05/2015; 5(2):212-20. DOI:10.1159/000375363

Publication Stats

17k Citations
2,174.29 Total Impact Points


  • 2011-2015
    • Karolinska Institutet
      • • KI Alzheimer's Disease Research Center - ADRC
      • • Department of Neurobiology, Care Sciences and Society - NVS
      Сольна, Stockholm, Sweden
  • 2005-2015
    • Stavanger University Hospital
      • • Department of Neurology
      • • Division of Psychiatry
      Stavenger, Rogaland, Norway
  • 2014
    • Sahlgrenska University Hospital
      Goeteborg, Västra Götaland, Sweden
    • Karolinska University Hospital
      Tukholma, Stockholm, Sweden
  • 2008-2014
    • University of Stavanger (UiS)
      Stavenger, Rogaland, Norway
  • 2013
    • Oslo University Hospital
      • Department of Radiology and Nuclear Medicine
      Kristiania (historical), Oslo County, Norway
  • 2010-2013
    • University of Oslo
      Kristiania (historical), Oslo, Norway
  • 2008-2011
    • King's College London
      • Wolfson Centre for Age-Related Diseases
      Londinium, England, United Kingdom
  • 2004-2011
    • University of Bergen
      • Institute of Medicine
      Bergen, Hordaland, Norway
  • 2009
    • Haukeland University Hospital
      Bergen, Hordaland, Norway
  • 1995-1996
    • NKS Olaviken, Hospital for Old Age Psychiatry
      Bergen, Hordaland, Norway