No abstract

The objective was to evaluate the construct validity of the Italian version of the Frontal Behavioural Inventory (FBI) and its usefulness in the differential diagnosis of dementias. Standard criteria were used in the clinical diagnosis of dementias in 83 patients and 33 agematched healthy volunteers. The FBI scale was translated from English into Italian language and back-translated. Cronbach's alpha, inter-rater and test-retest reliability, FBI convergent validity and discriminant analysis were calculated. FBI profile was compared between patients affected by frontotemporal lobar degeneration (FTLD) and Alzheimer's disease (AD). The FBI showed a high internal consistency and inter-rater reliability and it distinguished normal behavioural conditions from those presented in FTLD or AD. An 86.8% diagnostic accuracy was calculated by the discriminant analysis, selecting only age at disease onset and FBI, and particularly distinguishing behavioural variants within the FTLD spectrum. FTLD patients showed a characteristic behavioural profile. The FBI might be a reliable and useful diagnostic tool for dementias in clinical practice.

No abstract

Mild alterations in cognitive function are present in normal aging and severe cognitive alterations are a hallmark of Alzheimer's disease (AD). Cognitive deficits are prevalent in patients with schizophrenia (SCZ) and worsen with old age. We recently reported that elderly SCZ patients show reduced levels of amyloid-beta (Aβ)1-42 in cerebrospinal fluid (CSF). To further clarify the role of Aβ in cognitive decline, we analyzed the whole panel of CSF Aβ isoforms in elderly SCZ patients as well as in sporadic AD using SELDI TOF MS. The immunoproteomic study revealed, in all analyzed CSF samples, the presence of 15 different Aβ peptides. In CSF from SCZ, we detected an overall strong reduction of almost all Aβ species while in sporadic AD Aβ1-42 was the only peptide reduced. A significant independent association between Aβ1-40 levels and global cognition was found in SCZ. In addition, in SCZ patients, duration of therapy was positively associated with soluble amyloid precursor protein alpha levels, the total amount of CSF Aβ and the most abundant Aβ1-40 isoform. These data suggests a dysmetabolism of amyloid precursor protein in older SCZ patients. Thus, the quite comparable reduction of CSF Aβ1-42 in AD and in elderly SCZ patients reflects different pathophysiological dynamics in ageing brain.