%0 Journal Article %J J Alzheimers Dis %D 2018 %T The Diagnostic and Prognostic Value of a Dual-Tasking Paradigm in a Memory Clinic. %A Nielsen, Malene Schjnning %A Simonsen, Anja Hviid %A Siersma, Volkert %A Hasselbalch, Steen Gregers %A Hoegh, Peter %K Aged %K Alzheimer Disease %K Biomarkers %K Case-Control Studies %K Cognitive Dysfunction %K Disease Progression %K Female %K Humans %K Logistic Models %K Male %K Memory %K Middle Aged %K Neuropsychological Tests %K Prognosis %K Prospective Studies %K ROC Curve %X

BACKGROUND: Daily living requires the ability to perform dual-tasking. As cognitive skills decrease in dementia, performing a cognitive and motor task simultaneously become increasingly challenging and subtle gait abnormalities may even be present in pre-dementia stages. Therefore, a dual-tasking paradigm, such as the Timed Up and Go-Dual Task (TUG-DT), may be useful in the diagnostic assessment of mild cognitive impairment (MCI).

OBJECTIVE: To investigate the diagnostic and prognostic ability of a dual-tasking paradigm in patients with MCI or mild Alzheimer's disease (AD) and to evaluate the association between the dual-tasking paradigm and cerebrospinal fluid (CSF) AD biomarkers.

METHODS: The study is a prospective cohort study conducted in a clinical setting in two memory clinics. Eighty-six patients were included (28 MCI, 17 AD, 41 healthy controls (HC)). The ability to perform dual-tasking was evaluated by the TUG-DT. Patients underwent a standardized diagnostic assessment and were evaluated to determine progression yearly.

RESULTS: ROC curve analysis illustrated a high discriminative ability of the dual-tasking paradigm in separating MCI patients from HC (AUC: 0.78, AUC: 0.82) and a moderate discriminative ability in separating MCI from AD (AUC: 0.73, AUC: 0.55). Performance discriminated clearly between all groups (p < 0.01). Logistic regression analyses revealed a low prognostic value of the dual-tasking paradigm for progression and rate of cognitive decline. A moderately strong correlation between the dual-tasking paradigm and CSF AD biomarkers was observed.

CONCLUSION: In our study, we found that patients with MCI and mild AD have increasing difficulties in dual-tasking compared to healthy elderly. Hence, the dual-tasking paradigm may be a potential complement in the diagnostic assessment in a typical clinical setting.

%B J Alzheimers Dis %V 61 %P 1189-1199 %8 2018 %G eng %N 3 %1 http://www.ncbi.nlm.nih.gov/pubmed/29278887?dopt=Abstract %R 10.3233/JAD-161310 %0 Journal Article %J J Alzheimers Dis %D 2018 %T Effects of Physical Exercise on Alzheimer's Disease Biomarkers: A Systematic Review of Intervention Studies. %A Frederiksen, Kristian Steen %A Gjerum, Le %A Waldemar, Gunhild %A Hasselbalch, Steen Gregers %K Alzheimer Disease %K Biomarkers %K Exercise %K Hippocampus %K Humans %K Outcome Assessment (Health Care) %K Physical Therapy Modalities %X

Physical exercise may be an important adjunct to pharmacological treatment of Alzheimer's disease (AD). Animal studies indicate that exercise may be disease modifying through several mechanisms including reduction of AD pathology. We carried out a systematic review of intervention studies of physical exercise with hippocampal volume (on MRI), amyloid-β, total tau, phosphorylated tau in cerebrospinal fluid (CSF), 18F-FDG-PET or amyloid PET as outcome measures in healthy subjects, patients with subjective memory complaints, mild cognitive impairment, or AD. We identified a total of 8 studies of which 6 investigated the effects of exercise on hippocampal volume in healthy subjects and 1 on CSF biomarkers and 1 on hippocampal volume in AD, and none investigating the remaining outcome measures or patient groups. Methodological quality of identified studies was generally low. One study found a detrimental effect on hippocampal volume and one found a positive effect, whereas the remaining studies did not find an effect of exercise on outcome measures. The present systematic study identified a relatively small number of studies, which did not support an effect of exercise on hippocampal volume. Methodological issues such small to moderate sample sizes and inadequate ramdomization procedures further limits conclusions. Our findings highlight the difficulties in conducting high quality studies of exercise and further studies are needed before definite conclusions may be reached.

%B J Alzheimers Dis %V 61 %P 359-372 %8 2018 %G eng %N 1 %1 http://www.ncbi.nlm.nih.gov/pubmed/29154278?dopt=Abstract %R 10.3233/JAD-170567