Alzheimer Disease: Bronnick K

Aarsland D, Kurz M, Beyer M, Bronnick K, Piepenstock Nore S, Ballard C. · Norwegian Centre for Movement Disorders, Stavanger University Hospital, Stavanger, Norway. · Dement Geriatr Cogn Disord. · Pubmed #18204253 No free full text.

Abstract: BACKGROUND: The clinical diagnostic criteria for dementia with Lewy bodies (DLB) have a low sensitivity, and there are no generally accepted biomarkers to distinguish DLB from other dementias. Our aim was to identify biomarkers that may differentiate DLB from Alzheimer's disease (AD). METHOD: We performed a systematic literature search for studies of EEG, imaging techniques and genetic and CSF markers that provide sensitivity and specificity in the identification of DLB. RESULTS: The best evidence was for scintigraphy of the striatal dopamine transporter system using FP-CIT SPECT. Several small scintigraphy studies of cardiovascular autonomic function using metaiodobenzylguanidine SPECT have reported promising results. Studies exploring innovative techniques based on CSF have reported interesting findings for the combination of amyloid beta (abeta) isoforms as well as alpha-synuclein, and there are interesting results emerging from preliminary studies applying proteomic techniques. Data from studies using structural MRI, perfusion SPECT, genetics and EEG studies show differences between DLB and AD but only at a group level. CONCLUSION: Several potential biomarkers for the differential diagnosis of probable DLB and AD have shown good diagnostic accuracy in the research setting. Data from large multicentre studies and from studies with autopsy confirmation exist for scintigraphy of the dopamine transporter system. Future studies should explore its value in possible DLB and for clinical management and health economics.

Bronnick K, Emre M, Lane R, Tekin S, Aarsland D. · Norwegian Centre for Movement Disorders, Stavanger University Hospital, Helse Stavanger, Norway. · J Neurol Neurosurg Psychiatry. · Pubmed #17287236 No free full text.

Abstract: OBJECTIVE: To compare the profile of cognitive impairment in Alzheimer's disease (AD) with dementia associated with Parkinson's disease (PDD). METHODS: Neuropsychological assessment was performed in 488 patients with PDD and 488 patients with AD using the Mini-Mental State Examination (MMSE) and the Alzheimer's Disease Assessment Scale-cognitive subscale (ADAS-cog). Logistic regression analysis was used to investigate whether the diagnosis could be accurately predicted from the cognitive profile. Additionally, the cognitive profiles were compared with a normative group using standardised effect sizes (Cohen's d). RESULTS: Diagnosis was predicted from the cognitive profile, with an overall accuracy of 74.7%. Poor performance of the AD patients on the orientation test in ADAS-cog best discriminated between the groups, followed by poor performance of the PDD patients on the attentional task in MMSE. Both groups showed memory impairment, AD patients performing worse than PDD patients. CONCLUSION: The cognitive profile in PDD differs significantly from that in AD. Performance on tests of orientation and attention are best in differentiating the groups.