Showing papers by "Giuliano Binetti published in 2020"

Age at symptom onset and death and disease duration in genetic frontotemporal dementia: an international retrospective cohort study.

Abstract: Summary Background Frontotemporal dementia is a heterogenous neurodegenerative disorder, with about a third of cases being genetic. Most of this genetic component is accounted for by mutations in GRN, MAPT, and C9orf72. In this study, we aimed to complement previous phenotypic studies by doing an international study of age at symptom onset, age at death, and disease duration in individuals with mutations in GRN, MAPT, and C9orf72. Methods In this international, retrospective cohort study, we collected data on age at symptom onset, age at death, and disease duration for patients with pathogenic mutations in the GRN and MAPT genes and pathological expansions in the C9orf72 gene through the Frontotemporal Dementia Prevention Initiative and from published papers. We used mixed effects models to explore differences in age at onset, age at death, and disease duration between genetic groups and individual mutations. We also assessed correlations between the age at onset and at death of each individual and the age at onset and at death of their parents and the mean age at onset and at death of their family members. Lastly, we used mixed effects models to investigate the extent to which variability in age at onset and at death could be accounted for by family membership and the specific mutation carried. Findings Data were available from 3403 individuals from 1492 families: 1433 with C9orf72 expansions (755 families), 1179 with GRN mutations (483 families, 130 different mutations), and 791 with MAPT mutations (254 families, 67 different mutations). Mean age at symptom onset and at death was 49·5 years (SD 10·0; onset) and 58·5 years (11·3; death) in the MAPT group, 58·2 years (9·8; onset) and 65·3 years (10·9; death) in the C9orf72 group, and 61·3 years (8·8; onset) and 68·8 years (9·7; death) in the GRN group. Mean disease duration was 6·4 years (SD 4·9) in the C9orf72 group, 7·1 years (3·9) in the GRN group, and 9·3 years (6·4) in the MAPT group. Individual age at onset and at death was significantly correlated with both parental age at onset and at death and with mean family age at onset and at death in all three groups, with a stronger correlation observed in the MAPT group (r=0·45 between individual and parental age at onset, r=0·63 between individual and mean family age at onset, r=0·58 between individual and parental age at death, and r=0·69 between individual and mean family age at death) than in either the C9orf72 group (r=0·32 individual and parental age at onset, r=0·36 individual and mean family age at onset, r=0·38 individual and parental age at death, and r=0·40 individual and mean family age at death) or the GRN group (r=0·22 individual and parental age at onset, r=0·18 individual and mean family age at onset, r=0·22 individual and parental age at death, and r=0·32 individual and mean family age at death). Modelling showed that the variability in age at onset and at death in the MAPT group was explained partly by the specific mutation (48%, 95% CI 35–62, for age at onset; 61%, 47–73, for age at death), and even more by family membership (66%, 56–75, for age at onset; 74%, 65–82, for age at death). In the GRN group, only 2% (0–10) of the variability of age at onset and 9% (3–21) of that of age of death was explained by the specific mutation, whereas 14% (9–22) of the variability of age at onset and 20% (12–30) of that of age at death was explained by family membership. In the C9orf72 group, family membership explained 17% (11–26) of the variability of age at onset and 19% (12–29) of that of age at death. Interpretation Our study showed that age at symptom onset and at death of people with genetic frontotemporal dementia is influenced by genetic group and, particularly for MAPT mutations, by the specific mutation carried and by family membership. Although estimation of age at onset will be an important factor in future pre-symptomatic therapeutic trials for all three genetic groups, our study suggests that data from other members of the family will be particularly helpful only for individuals with MAPT mutations. Further work in identifying both genetic and environmental factors that modify phenotype in all groups will be important to improve such estimates. Funding UK Medical Research Council, National Institute for Health Research, and Alzheimer's Society.

New insights on the genetic etiology of Alzheimer’s and related dementia

Abstract: Alzheimer’s disease (AD) is a severe and incurable neurodegenerative disease, and the failure to find effective treatments suggests that the underlying pathology remains poorly understood. Due to its strong heritability, deciphering the genetic landscape of AD and related dementia (ADD) is a unique opportunity to advance our knowledge. We completed a meta-analysis of genome-wide association studies (39,106 clinically AD-diagnosed cases, 46,828 proxy-ADD cases and 401,577 controls) with the most promising signals followed-up in 25,392 independent AD cases and 276,086 controls. We report 75 risk loci for ADD, including 42 novel ones. Pathway-enrichment analyses confirm the involvement of amyloid/Tau pathways, highlight the role of microglia and its potential interaction with APP metabolism. Numerous genes exhibited differential expression or splicing in AD-related conditions and gene prioritization implies EGFR signaling and TNF-α pathway through LUBAC complex. We also generated a novel polygenic risk score strongly associated with the risk of future dementia or progression from mild cognitive impairment to dementia. In conclusion, by more than doubling the number of loci associated with ADD risk, our study offers new insights into the pathophysiological processes underlying AD and offers additional therapeutic entry-points and tools for translational genomics.

Diagnostic and prognostic value of serum NfL and p-Tau181 in frontotemporal lobar degeneration

Abstract: Objective To assess the diagnostic and prognostic value of serum neurofilament light (NfL) and serum phospho-Tau181 (p-Tau181) in a large cohort of patients with frontotemporal lobar degeneration (FTLD). Methods In this retrospective study, performed on 417 participants, we analysed serum NfL and p-Tau181 concentrations with an ultrasensitive single molecule array (Simoa) approach. We assessed the diagnostic values of serum biomarkers in the differential diagnosis between FTLD, Alzheimer’s disease (AD) and healthy ageing; their role as markers of disease severity assessing the correlation with clinical variables, cross-sectional brain imaging and neurophysiological data; their role as prognostic markers, considering their ability to predict survival probability in FTLD. Results We observed significantly higher levels of serum NfL in patients with FTLD syndromes, compared with healthy controls, and lower levels of p-Tau181 compared with patients with AD. Serum NfL concentrations showed a high accuracy in discriminating between FTLD and healthy controls (area under the curve (AUC): 0.86, p Conclusions The assessment of serum NfL and p-Tau181 may provide a comprehensive view of FTLD, aiding in the differential diagnosis, in staging disease severity and in defining survival probability.

Serum Glial Fibrillary Acidic Protein (GFAP) Is a Marker of Disease Severity in Frontotemporal Lobar Degeneration.

Abstract: Background It is still unknown if serum glial fibrillary acidic protein (GFAP) is a useful marker in frontotemporal lobar degeneration (FTLD). Objective To assess the diagnostic and prognostic value of serum GFAP in a large cohort of patients with FTLD. Methods In this retrospective study, performed on 406 participants, we measured serum GFAP concentration with an ultrasensitive Single molecule array (Simoa) method in patients with FTLD, Alzheimer's disease (AD), and in cognitively unimpaired elderly controls. We assessed the role of GFAP as marker of disease severity by analyzing the correlation with clinical variables, neurophysiological data, and cross-sectional brain imaging. Moreover, we evaluated the role of serum GFAP as a prognostic marker of disease survival. Results We observed significantly higher levels of serum GFAP in patients with FTLD syndromes, except progressive supranuclear palsy, compared with healthy controls, but not compared with AD patients. In FTLD, serum GFAP levels correlated with measures of cognitive dysfunction and disease severity, and were associated with indirect measures of GABAergic deficit. Serum GFAP concentration was not a significant predictor of survival. Conclusion Serum GFAP is increased in FTLD, correlates with cognition and GABAergic deficits, and thus shows promise as a biomarker of disease severity in FTLD.

Pathogenic Huntingtin Repeat Expansions in Patients with Frontotemporal Dementia and Amyotrophic Lateral Sclerosis

Abstract: To examine the role of repeat expansions in the pathogenesis of frontotemporal dementia (FTD) and amyotrophic lateral sclerosis (ALS), we performed repeat sizing of ten genetic loci previously implicated in neurodegenerative diseases. We examined whole-genome sequence data from 2,442 FTD/ALS patients, 2,599 Lewy body dementia (LBD) patients, and 3,158 neurologically healthy subjects. Pathogenic expansions (range: 40 to 64 CAG repeats) in the huntingtin (HTT) gene were found in three (0.12%) patients diagnosed with pure FTD/ALS syndromes but were not present in the LBD or healthy cohorts. We replicated our findings in an independent cohort, and identified five (0.14%) out of 3,674 FTD/ALS patients harboring pathogenic HTT CAG expansions. Postmortem evaluations of two patients revealed huntingtin-positive, as well as TDP43- and ubiquitin-positive aggregates, predominantly in the frontal cortex, without neostriatal atrophy. Our findings reveal an etiological relationship between HTT repeat expansions and FTD/ALS syndromes, and indicate that genetic screening of FTD/ALS patients for HTT repeat expansions should be considered.

Effects of Transcranial Direct Current Stimulation on Episodic Memory in Amnestic Mild Cognitive Impairment: A Pilot Study.

Abstract: Objectives Episodic memory is impaired in amnestic mild cognitive impairment (aMCI), which is posited as a potential prodromal form of Alzheimer's disease. Reactivated existing memories become sensitive to modification during reconsolidation. There is evidence that the lateral prefrontal cortex (PFC) plays causal role in episodic memory reconsolidation. Transcranial direct current stimulation (tDCS) applied to the PFC after a contextual reminder enhanced episodic memory performance up to 1 month, conceivably through reconsolidation, in older adults with subjective memory complaints, a condition that may represent a "pre-mild cognitive impairment" stage. The aim of this pilot study was to test the effect of PFC-tDCS (anode over left lateral PFC, cathode over right supraorbital area) after a contextual reminder on episodic memory in older adults with aMCI. Method Older adults with aMCI learned a list of words. Twenty-four hours later, tDCS (Active or Sham) was applied after a contextual reminder. Memory retrieval (free recall and recognition) was tested 48 hrs and 1 month after the learning session. Results Active tDCS enhanced recognition memory relative to Sham stimulation. Discussion Modulating reconsolidation with PFC-tDCS might be a novel intervention to enhance episodic memories in aMCI.

Effectiveness of an Innovative Cognitive Treatment and Telerehabilitation on Subjects With Mild Cognitive Impairment: A Multicenter, Randomized, Active-Controlled Study.

Abstract: Background In recent years, the potential usefulness of cognitive training procedures in normal aging and mild cognitive impairment (MCI) have received increased attention. Objective The main aim of this study was to evaluate the efficacy of the face-to-face cognitive virtual reality rehabilitation system (VRRS) and to compare it to that of face-to-face cognitive treatment as usual for individuals with MCI. Moreover, we assessed the possibility of prolonging the effects of treatment with a telerehabilitation system. Methods A total of 49 subjects with MCI were assigned to 1 of 3 study groups in a randomized controlled trial design: (a) those who received face-to-face cognitive VRRS (12 sessions of individualized cognitive rehabilitation over 4 weeks) followed by telerehabilitation (36 sessions of home-based cognitive VRRS training, three sessions for week); (b) those who received face-to-face cognitive VRRS followed by at-home unstructured cognitive stimulation (36 sessions of home-based unstructured cognitive stimulation, three sessions for week); and (c) those who received face-to-face cognitive treatment as usual (12 sessions of face-to-face cognitive treatment as usual). Results An improvement in memory, language and visuo-constructional abilities was observed after the end of face-to-face VRRS treatment compared to face-to-face treatment as usual. The application of home-based cognitive VRRS telerehabilitation seems to induce more maintenance of the obtained gains than home-based unstructured stimulation. Discussion The present study provides preliminary evidence in support of individualized VRRS treatment and telerehabilitation delivery for cognitive rehabilitation and should pave the way for future studies aiming at identifying optimal cognitive treatment protocols in subjects with MCI. Clinical trial registration www.ClinicalTrials.gov, identifier NCT03486704.

Eating Behavior in Aging and Dementia: The Need for a Comprehensive Assessment

Abstract: Eating behavior can change during aging due to physiological, psychological, and social changes. Modifications can occur at different levels: (1) in food choice, (2) in eating habits, and (3) in dietary intake. A good dietary behavior, like the Mediterranean dietary pattern, can be a protective factor for some aging related pathologies, such as dementia, while a worse eating behavior can lead to pathological conditions such as malnutrition. Changes in eating behavior can also be linked to the onset of dementia: for some types of dementia, such as frontotemporal dementia, dietary changes are one of the key clinical diagnostic feature, for others, like Alzheimer's disease, weight loss is a clinical reported feature. For these reasons, it is important to be able to assess eating behavior in a proper way, considering that there are normal age-related changes. An adequate assessment of dietary behavior can help to plan preventive intervention strategies for heathy aging or can help to identify abnormal behaviors that underline aging related-diseases. In this review, we have analyzed normal age-related and dementia-related changes and the tools that can be used to assess eating behavior. Thus, we make recommendations to screening and monitoring eating behavior in aging and dementia, and to adopt these tools in clinical practice.

Polymorphic Genetic Markers of the GABA Catabolism Pathway in Alzheimer's Disease.

Abstract: BACKGROUND The compilation of a list of genetic modifiers in Alzheimer's disease (AD) is an open research field. The GABAergic system is affected in several neurological disorders but its role in AD is largely understudied. OBJECTIVE/METHODS As an explorative study, we considered variants in genes of GABA catabolism (ABAT, ALDH5A1, AKR7A2), and APOE in 300 Italian patients and 299 controls. We introduce a recent multivariate method to take into account the individual APOE genotype, thus controlling for the effect of the discrepant allele distributions in cases versus controls. We add a genotype-phenotype analysis based on age at onset and the Mini-Mental State Evaluation score. RESULTS On the background of strongly divergent APOE allele distributions in AD versus controls, two genotypic interactions that represented a subtle but significant peculiarity of the AD cohort emerged. The first is between ABAT and APOE, and the second between some ALDH5A1 genotypes and APOE. Decreased SSADH activity is predicted in AD carriers of APOEɛ4, representing an additional suggestion for increased oxidative damage. CONCLUSION We identified a difference between AD and controls, not in a shift of the allele frequencies at genes of the GABA catabolism pathway, but rather in gene interactions peculiar of the AD cohort. The emerging view is that of a multifactorial contribution to the disease, with a main risk factor (APOE), and additional contributions by the variants here considered. We consider genes of the GABA degradation pathway good candidates as modifiers of AD, contributing to energy impairment in AD brain.

Iron Serum Markers Profile in Frontotemporal Lobar Degeneration.

Abstract: Frontotemporal lobar degeneration (FTLD) is a progressive neurodegenerative syndrome. Defects of copper (Cu) and iron (Fe) homeostasis are involved in the development of several neurodegenerative diseases and their homeostasis is interconnected by the Cu-protein ceruloplasmin (Cp), responsible for Fe oxidative state. In this study we assessed Fe, transferrin (Trf), ferritin, Cp specific activity (eCp/iCp), Cp/Trf ratio, and Trf saturation in 60 FTLD patients and 43 healthy controls, and discussed the results in relation to Cu homeostasis. The significant decrease of the eCp/iCp in the FTLD patients supports the involvement of Fe imbalance in the onset and progression of FTLD.