Association between Neuropsychological Performance and CSF Profile in Subjective Cognitive Decline: Towards the Diagnosis of Preclinical AD.

BACKGROUND: In the perspective of novel treatments with disease-modifying drugs, a timely diagnosis of Alzheimer's' disease (AD) at preclinical phase represents a major issue. To this purpose, in clinical setting, there is the need to detect the earliest cognitive symptoms not yet fulfilling Mild Cognitive Impairment criteria, in order to proceed to biomarker assessment for diagnostic definition. In terms of cognitive performance, Subjective Cognitive Decline (SCD) is still a controversial entity, due to the difficulty of reliably measuring subtle deficits. OBJECTIVE: To evaluate the possibility to predict the presence of AD-like CSF pattern in SCD individuals, according to their neuropsychological performance assessed by means of both traditional and computerized measures. DESIGN: Retrospective study. SETTING: Clinical setting (Centre for Memory Disturbances, Section of Neurology, University Hospital of Perugia, Italy). PARTICIPANTS: 74 consecutive SCD subjects who underwent an in-depth (paper-pencil and computerized) neuropsychological assessment and CSF analysis for AD biomarkers (Aß42/Aß40 ratio, phospho-tau, total tau). MEASUREMENTS: Neuropsychological assessment was composed of traditional tests assessing five cognitive domains (verbal memory, attention, executive functions, language, visuo-spatial abilities) and computerized tasks from CAmbridge Neuropsychological Test Automated Battery (CANTAB) (Pattern Recognition Memory, Paired Associates Learning and Spatial Working Memory). According to their performance at traditional tests, SCD individuals were categorized into cognitively normal (CN) and subtle impaired (SI); with respect to CANTAB, they were defined as CANTAB- in presence of normal performance, and CANTAB+ in presence of at least one pathological score. The subgroup with completely normal performance was defined as CN/CANTAB-, and the subgroup with impairment in both measures as SI/CANTAB+. Differences in prevalence of A/T/N profile according to cognitive profiles were assessed by Fisher's exact text for count data. RESULTS: None of CN/CANTAB- subjects showed A+/T+ status. SI/CANTAB+ subjects showed a significantly high prevalence of A+/T+ profile (14/35, 40%, p=0.03 vs CN/CANTAB-). CONCLUSION: The neuropsychological profile may be of help in identifying SCD subjects requiring biomarker assessment. If confirmed in larger cohorts, the combination of traditional and computerized tests (namely, CANTAB) might represent a feasible strategy in clinical setting for carrying out biomarker assessment in individuals before the MCI stage. Detection of AD in these subjects would give them the highest chances to halt disease progression by means of disease modifying treatments.

HIV-Dementia Scale as a screening tool for the detection of subcortical cognitive deficits: validation of the Italian version.

Mini-Mental State Examination (MMSE) lacks of sensitivity in detecting cognitive deficits associated with subcortical damage. The HIV-Dementia Scale (HDS), a screening tool originally created for detecting cognitive impairment due to subcortical damage in HIV + patients, has proved to be useful in other neurological diseases. Until now, an Italian version of the HDS is not available. We aimed at: (1) validating the HDS Italian version (HDS-IT) in a cohort of cognitively healthy subjects (CN); (2) exploring the suitability of HDS-IT in detecting cognitive impairment due to subcortical damage (scCI). The psychometric properties of the HDS-IT were assessed in 180 CN (mean age 67.6 ± 8.3, range 41-84) with regard to item-total correlation, test-retest reliability and convergent validity with MMSE. Item-total correlations ranged 0.44-0.72. Test-retest reliability was 0.70 (p < 0.001). The HDS-IT scores were positively associated with MMSE score (rS = 0.49, p < 0.001). Then, both the HDS-IT and the MMSE were administered to 44 scCI subjects (mean age 64.9 ± 10.6, range 41-84). Mean HDS-IT total score was close to the original version and significantly lower in the scCI group compared to CN (8.6 ± 3.6 vs. 12.6 ± 2.5, p < 0.001). ROC analysis yielded an optimal cutoff value of 11, with sensitivity of 0.70 and specificity of 0.82. Patients showed poorer scores on HDS-IT compared to CN (12.6 ± 2.5 vs. 8.6 ± 3.6, p < 0.001). Our results support the use of HDS-IT as a screening tool suitable for detecting cognitive deficits with prevalent subcortical pattern, being complementary to MMSE in clinical practice.

Time trends, frequency, characteristics and prognosis of short-duration transient global amnesia.

BACKGROUND AND PURPOSE: Transient global amnesia (TGA) is characterized by a sudden onset of anterograde amnesia lasting up to 24 h. One major differential for TGA is transient epileptic amnesia, which typically lasts < 1 h. However, TGA can also be short in duration and little is known about the time trends, characteristics and prognosis of TGA cases lasting < 1 h. METHODS: We compared the clinical features of TGA ascertained in two independent cohort studies in Oxfordshire, UK [Oxford cohort 1977-1987 versus Oxford Vascular Study (OXVASC) 2002-2018] to determine the time trends of clinical features of TGA. Results were validated in another independent contemporary TGA cohort in Italy [Northern Umbria TGA registry (NU) 2002-2018]. We compared the risk factors, clinical features and long-term prognosis (major cardiovascular events, recurrent TGA and seizure/epilepsy) of patients presenting with episodes lasting < 1 h versus those lasting ≥ 1 h. RESULTS: Overall, 639 patients with TGA were included (114 Oxford cohort, 100 OXVASC, 425 NU). Compared with the original Oxford cohort, there were more cases with TGA lasting < 1 h in OXVASC [32 (32.0%) vs. 9 (8.8%)] and NU (11.8% vs. 8.8% in Oxford cohort). In both OXVASC and NU, patient age, vascular risk factors and clinical features were largely similar between those with TGA lasting < 1 h versus those lasting ≥ 1 h. Moreover, there was no difference in the long-term risk of seizure/epilepsy or major cardiovascular events between TGA lasting < 1 h versus TGA lasting ≥ 1 h. CONCLUSIONS: Short-duration TGA episodes (<1 h) were not uncommon and were more frequent than in earlier studies. The clinical features and long-term prognosis of short-duration TGA did not differ from more typical episodes lasting ≥ 1 h.