Purpose
We aim to report the quality of accuracy studies investigating the utility of
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Ffluorodeoxyglucose (FDG)-PET in supporting the diagnosis of prodromal Alzheimer’s Disease (AD), ...frontotemporal lobar degeneration (FTLD) and prodromal dementia with Lewy bodies (DLB) in mild cognitive impairment (MCI) subjects, and the corresponding recommendations made by a panel of experts.
Methods
Seven panellist, four from the European Association of Nuclear Medicine, and three from the European Academy of Neurology, produced recommendations taking into consideration the incremental value of FDG-PET, as added on clinical-neuropsychological examination, to ascertain the aetiology of MCI (AD, FTLD or DLB). A literature search using harmonized population, intervention, comparison, and outcome (PICO) strings was performed, and an evidence assessment consistent with the European Federation of Neurological Societies guidance was provided. The consensual recommendation was achieved based on Delphi rounds.
Results
Fifty-four papers reported the comparison of interest. The selected papers allowed the identification of FDG patterns that characterized MCI due to AD, FTLD and DLB. While clinical outcome studies supporting the diagnosis of MCI due to AD showed varying accuracies (ranging from 58 to 100%) and varying areas under the receiver-operator characteristic curves (0.66 to 0.97), no respective data were identified for MCI due to FTLD or for MCI due to DLB. However, the high negative predictive value of FDG-PET and the existence of different disease-specific patterns of hypometabolism support the consensus recommendations for the clinical use of this imaging technique in MCI subjects.
Conclusions
FDG-PET has clinical utility on a fair level of evidence in detecting MCI due to AD. Although promising also in detecting MCI due to FTLD and MCI due to DLB, more research is needed to ultimately judge the clinical utility of FDG-PET in these entities.
subjective cognitive decline (SCD) refers to the subjective experience of cognitive decline in the absence of detectable cognitive impairment. SCD has been largely studied as a risk condition for ...cognitive decline. Empirical observations suggest that persons with SCD are heterogeneous, including individuals with early Alzheimer's disease and others with psychological vulnerabilities and/or physical comorbidity. The semiology of SCD is still in its infancy, and the features predicting cognitive decline are poorly defined. The present study aims to identify subgroups of SCD using a data-driven approach and study their clinical evolution across 8 years.
the study population is the InveCe.Ab population-based cohort, including cognitively unimpaired people aged 70-74 years and followed for 8 years. Hierarchical cluster analysis (HCA) was carried out to identify distinct SCD subgroups based on nine clinical and cognitive features. Longitudinal changes by baseline SCD status were estimated using linear mixed models for cognitive decline and Cox proportional-hazard model for all-cause dementia risk.
out of 956 individuals, 513 were female (54%); and the mean age was 72.1 (SD = 1.3), education was 7.2 (3.3), and 370 (39%) reported cognitive complaints (SCD). The HCA resulted in two clusters (SCD1 and SCD2). SCD2 were less educated and had more comorbidities, cardiovascular risk and depressive symptoms than SCD1 and controls. SCD2 presented steeper cognitive decline (Mini-Mental State Examination; β = -0.31) and increased all-cause dementia risk (hazard-ratio = 3.4).
at the population level, basic clinical information can differentiate individuals with SCD at higher risk of developing dementia, underlining the heterogeneous nature of this population even in a sample selected for a narrow age range, in a specific geographic area.
To comprehensively identify the determinants of quality of life (QoL) in a population study sample of persons aged 18-50 and 50+.
In this observational, cross-sectional study, QoL was measured with ...the WHOQOL-AGE, a brief instrument designed to measure QoL in older adults. Eight hierarchical regression models were performed to identify determinants of QoL. Variables were entered in the following order: Sociodemographic; Health Habits; Chronic Conditions; Health State description; Vision and Hearing; Social Networks; Built Environment. In the final model, significant variables were retained. The final model was re-run using data from the three countries separately.
Complete data were available for 5639 participants, mean age 46.3 (SD 18.4). The final model accounted for 45% of QoL variation and the most relevant contribution was given by sociodemographic data (particularly age, education level and living in Finland: 17.9% explained QoL variation), chronic conditions (particularly depression: 4.6%) and a wide and rich social network (4.6%). Other determinants were presence of disabling pain, learning difficulties and visual problems, and living in usable house that is perceived as non-risky. Some variables were specifically associated to QoL in single countries: age in Poland, alcohol consumption in Spain, angina in Finland, depression in Spain, and self-reported sadness both in Finland and Poland, but not in Spain. Other were commonly associated to QoL: smoking status, bodily aches, being emotionally affected by health problems, good social network and home characteristics.
Our results highlight the importance of modifiable determinants of QoL, and provide public health indications that could support concrete actions at country level. In particular, smoking cessation, increasing the level of physical activity, improving social network ties and applying universal design approach to houses and environmental infrastructures could potentially increase QoL of ageing population.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Aim
To assess the clinical utility of FDG-PET as a diagnostic aid for differentiating Alzheimer’s disease (AD; both typical and atypical forms), dementia with Lewy bodies (DLB), frontotemporal lobar ...degeneration (FTLD), vascular dementia (VaD) and non-degenerative pseudodementia.
Methods
A comprehensive literature search was conducted using the PICO model to extract evidence from relevant studies. An expert panel then voted on six different diagnostic scenarios using the Delphi method.
Results
The level of empirical study evidence for the use of FDG-PET was considered good for the discrimination of DLB and AD; fair for discriminating FTLD from AD; poor for atypical AD; and lacking for discriminating DLB from FTLD, AD from VaD, and for pseudodementia. Delphi voting led to consensus in all scenarios within two iterations. Panellists supported the use of FDG-PET for all PICOs—including those where study evidence was poor or lacking—based on its negative predictive value and on the assistance it provides when typical patterns of hypometabolism for a given diagnosis are observed.
Conclusion
Although there is an overall lack of evidence on which to base strong recommendations, it was generally concluded that FDG-PET has a diagnostic role in all scenarios. Prospective studies targeting diagnostically uncertain patients for assessing the added value of FDG-PET would be highly desirable.
Background Preclinical and pathology evidence suggests an involvement of brain dopamine (DA) circuitry in Alzheimer's disease (AD). We in vivo investigated if, when, and in which target regions ...123IFP-CIT-SPECT regional binding and molecular connectivity are damaged along the AD course. Methods We retrospectively selected 16 amyloid-positive subjects with mild cognitive impairment due to AD (AD-MCI), 22 amyloid-positive patients with probable AD dementia (AD-D), and 74 healthy controls, all with available 123IFP-CIT-SPECT imaging. We tested whether nigrostriatal vs. mesocorticolimbic dopaminergic targets present binding potential loss, via MANCOVA, and alterations in molecular connectivity, via partial correlation analysis. Results were deemed significant at p < 0.05, after Bonferroni correction for multiple comparisons. Results We found significant reductions of 123IFP-CIT binding in both AD-MCI and AD-D compared to controls. Binding reductions were prominent in the major targets of the ventrotegmental-mesocorticolimbic pathway, namely the ventral striatum and the hippocampus, in both clinical groups, and in the cingulate gyrus, in patients with dementia only. Within the nigrostriatal projections, only the dorsal caudate nucleus showed reduced 123IFP-CIT binding, in both groups. Molecular connectivity assessment revealed a widespread loss of inter-connections among subcortical and cortical targets of the mesocorticolimbic network only (poor overlap with the control group as expressed by a Dice coefficient less than or equai to 0.25) and no alterations of the nigrostriatal network (high overlap with controls, Dice coefficient = 1). Conclusion Local- and system-level alterations of the mesocorticolimbic dopaminergic circuitry characterize AD, already in prodromal disease phases. These results might foster new therapeutic strategies for AD. The clinical correlates of these findings deserve to be carefully considered within the emergence of both neuropsychiatric symptoms and cognitive deficits. Keywords: Biomarker, Dopamine, Molecular connectivity, Substantia nigra, Ventral tegmental area
Timely detection of cognitive decline in primary care is essential to promote an appropriate care pathway and enhance the benefits of interventions. We present the results of a study aimed to ...evaluate the effectiveness of an educational intervention addressed to Italian family physicians (FPs) to improve timely detection and management of cognitive decline.
We conducted a pre-post study in six Italian health authorities (HAs) involving 254 FPs and 3,736 patients. We measured process and outcome indicators before the intervention (1 January 2014 to 31 December 2016) and after the intervention (1 January 2018 to 31 December 2019). One interactive face-to-face session workshop was delivered by local cognitive disorders and dementia specialists and FP advisors at each HA, in the period September 2017-December 2017. The session focused on key messages of the local Diagnostic and Therapeutic Care Pathway (DTCP) or regional guidelines: (a) the role of the FP for a timely suspicion of cognitive decline is fundamental; (b) when cognitive decline is suspected, the role of the FP is active in the diagnostic work-up; (c) FP's knowledge on pharmacological and non-pharmacological interventions is essential to improve the management of patients with cognitive decline.
An overall improvement in diagnostic procedures and management of patients with cognitive decline by FPs after the intervention was observed. The number of visits per year performed by FPs increased, and the time interval between the first FP consultation and the diagnosis was optimized. Neuroleptic use significantly decreased, whereas the use of benzodiazepines remained steadily high. Non-pharmacological interventions, or use of support services, were underrepresented even in the post-intervention. Differences among the participating HAs were identified and discussed.
Results from this study suggest the success of the educational intervention addressed to FPs in improving early detection and management of cognitive decline, highlighting the importance to continue medical education in this field. At the same time, further initiatives of care pathway dissemination and implementation should promote strategies to enhance interactions between primary and secondary care optimizing the collaboration between FPs and specialists.
Abstract A change in neural connectivity of brain structures implicated in the memory of negative life events has been hypothesized to explain the enhancement of memory encoding during the processing ...of negative stimuli in depressed patients. Here, we investigated the effects of the interaction between negative life events and the 5-HTTLPR genotype – a polymorphism of the serotonin transporter gene – on the functional and structural connectivity of the hippocampal area in 34 healthy women. All participants were genotyped for the presence of the 5-HTTLPR short variant and for the A/G single-nucleotide polymorphism; they underwent clinical assessment including structured diagnostic interviews to exclude the presence of psychiatric disorders and to assess the presence of stressful life events. Resting state functional magnetic resonance imaging and diffusion tensor imaging scans were performed. We found significant interactions between stressful events and the 5-HTTLPR genotype in both the functional connectivity of the parahippocampus with the posterior cingulate cortex and the structural connectivity between the hippocampus and both the amygdala and the putamen. In addition, we found several genotype-related differences in the relationship between functional/structural connectivity of the hippocampal area and the ability to update expectations or stress-related phenotypes, such as anxiety symptoms. If confirmed by future studies, these mechanisms may clarify the role of the 5HTTLPR genotype as a risk factor for depression, in interaction with negative events.
Alzheimer disease (AD) neuropathologic changes are β-amyloid (Aβ) deposition, pathologic tau, and neurodegeneration. Dual-phase amyloid PET might be able to evaluate Aβ deposition and ...neurodegeneration with a single tracer injection. Early-phase amyloid PET scans provide a proxy for cerebral perfusion, which has shown good correlations with neural dysfunction measured through metabolic consumption, whereas the late frames depict amyloid distribution. Our study aimed to assess the comparability between early-phase amyloid PET scans and 18F-FDG PET brain topography at the individual level and their ability to discriminate patients. Methods: One hundred sixty-six subjects evaluated at the Geneva Memory Center, ranging from no cognitive impairment to mild cognitive impairment and dementia, underwent early-phase amyloid PET-using either 18F-florbetapir (eFBP) (n = 94) or 18F-flutemetamol (eFMM) (n = 72)-and 18F-FDG PET. Aβ status was assessed. SUV ratios (SUVRs) were extracted to evaluate the correlation of eFBP/eFMM and their respective 18F-FDG PET scans. The single-subject procedure was applied to investigate hypometabolism and hypoperfusion maps and their spatial overlap by the Dice coefficient. Receiver-operating-characteristic analyses were performed to compare the discriminative power of eFBP/eFMM and 18F-FDG PET SUVR in AD-related meta–regions of interest between Aβ-negative healthy controls and cases in the AD continuum. Results: Positive correlations were found between eFBP/eFMM and 18F-FDG PET SUVR independently of Aβ status and Aβ radiotracer (R > 0.72, P < 0.001). eFBP/eFMM single-subject analysis revealed clusters of significant hypoperfusion with good correspondence to hypometabolism topographies, independently of the underlying neurodegenerative patterns. Both eFBP/eFMM and 18F-FDG PET SUVR significantly discriminated AD patients from controls in the AD-related meta–regions of interest (eFBP area under the curve AUC, 0.888; eFMM AUC, 0.801), with 18F-FDG PET performing slightly better, although not significantly (all P values higher than 0.05), than others (18F-FDG AUC, 0.915 and 0.832 for subjects evaluated with eFBP and eFMM, respectively). Conclusion: The distribution of perfusion was comparable to that of metabolism at the single-subject level by parametric analysis, particularly in the presence of a high neurodegeneration burden. Our findings indicate that eFBP and eFMM imaging can replace 18F-FDG PET imaging, as they reveal typical neurodegenerative patterns or allow exclusion of the presence of neurodegeneration. The findings show cost-saving capacities of amyloid PET and support routine use of the modality for individual classification in clinical practice.
Abstract Background A recent genome-wide association study on Major Depressive Disorder (MDD) identified a specific association with a non-synonymous polymorphism (rs2522833) of a gene encoding the ...presynaptic protein piccolo (PCLO). A high percentage of patients who develop MDD have particular temperamental traits, such as passivity, pessimism, indecisiveness, and low self-esteem, which are related to the subsequent development of depression. The aims of this study were to perform a replicate case–control study and to conduct the first association study between the rs2522833 polymorphism and depression-related personality traits using the Temperament and Character Inventory (TCI) in a healthy subject sample. Methods A total of 522 MDD patients and 375 healthy volunteers were enrolled in the study. Two hundred and forty-six controls agreed to fill out the TCI. Results The results showed that rs2522833 CC homozygotes were more frequent among the depressed patients than in the controls (p < 0.01). The C allele distribution showed a trend in the same direction (p = 0.08). Among controls, we found that the C allele carriers were associated with personality traits increasing vulnerability to depression, including higher Harm Avoidance (HA) and lower in Novelty Seeking (NS). In particular, C allele carriers were more fearful (HA2) and fatigable (HA4), and less impulsive/more deliberate (NS2) and less extravagant/more frugal (NS3). Limitations The absence of possible epistatic interaction effect. Conclusions These results provide further support for the involvement of the PCLO gene in MDD and show that this effect may be mediated by influencing personality traits that increase the risk of major depression.
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