Elucidating the downstream impact of exogenous hormones on the aging brain will have far-reaching consequences for understanding why Alzheimer's disease (AD) predominates in women almost twofold over men. We tested the extent to which menopausal hormone therapy (HT) use is associated with later-life amyloid-β (Aβ) and tau accumulation using PET on = 146 baseline clinically normal women, aged 51 to 89 years. Women were scanned over a 4.
View Article and Find Full Text PDFImpulse control disorders (ICDs) are frequent and particularly distressing neuropsychiatric symptoms in patients with Parkinson's disease (PD) which are related to impaired behavioural inhibition. Multiple PET imaging studies indicate that striatal dopaminergic abnormalities contribute to hyperdopaminergic functioning in PD patients with ICD (PDICD+) and to the dysregulation of the limbic fronto-striatal networks which are critical for reward-related decision impulsivity. However, the serotonergic system is central to response inhibition and plays a critical role in neuropsychiatric symptoms in PD, but its role remains undetermined in PDICD.
View Article and Find Full Text PDFImportance: Alzheimer disease (AD) predominates in females at almost twice the rate relative to males. Mounting evidence in adults without AD indicates that females exhibit higher tau deposition than age-matched males, particularly in the setting of elevated β-amyloid (Aβ), but the evidence for sex differences in tau accumulation rates is inconclusive.
Objective: To examine whether female sex is associated with faster tau accumulation in the setting of high Aβ (as measured with positron emission tomography [PET]) and the moderating influence of sex on the association between APOEε4 carrier status and tau accumulation.
Introduction: Specific features of subjective cognitive decline (SCD-plus) have been proposed to indicate an increased risk of preclinical Alzheimer's disease (AD). However, few studies have examined how these features relate to AD biomarkers in cognitively unimpaired (CU) older adults.
Methods: Meta-analyses were performed using cross-sectional data from nine cohorts (n = 7219, mean age (SD): 71.
Cognitive resilience (CR) describes the phenomenon of individuals evading cognitive decline despite prominent Alzheimer's disease neuropathology. Operationalization and measurement of this latent construct is non-trivial as it cannot be directly observed. The residual approach has been widely applied to estimate CR, where the degree of resilience is estimated through a linear model's residuals.
View Article and Find Full Text PDFAlzheimers Dement
December 2024
Background And Purpose: Disabling dystonia despite optimal medical treatment is common in Wilson disease (WD). No controlled study has evaluated the effect of deep brain stimulation (DBS) on dystonia related to WD. This study was undertaken to evaluate the efficacy of DBS on dystonia related to WD.
View Article and Find Full Text PDFBackground: Stronger resting-state functional connectivity of the default mode and frontoparietal control networks has been associated with cognitive resilience to Alzheimer's disease related pathology and neurodegeneration in smaller cohort studies.
Objectives: We investigated whether these networks are associated with longitudinal CR to AD biomarkers of beta-amyloid (Aβ).
Design: Longitudinal mixed.
Few studies have considered the influence of motor sign asymmetry on motivated behaviors in de novo drug-naïve Parkinson's disease (PD). We tested whether motor sign asymmetry could be associated with different motivated behavior patterns in de novo drug-naïve PD. We performed a cross-sectional study in 128 de novo drug-naïve PD patients and used the Ardouin Scale of Behavior in Parkinson's disease (ASBPD) to assess a set of motivated behaviors.
View Article and Find Full Text PDFThe Face Name Associative Memory Exam (FNAME) was introduced into the NIH Toolbox as part of the ARMADA study and establishes normative data for diverse participants, ages 64 to 85+, and proposes cutoff scores between biomarker positive versus negative (+/-) groups. The FNAME was administered to 257 participants across the clinical spectrum with 122 having amyloid biomarkers. Linear regression explored the association between demographics and FNAME and between amyloid (+/-) groups.
View Article and Find Full Text PDFBackground: Impulse control disorders (ICDs) are frequently encountered in Parkinson's disease (PD).
Objectives: We aimed to assess whether clonidine, an α2-adrenergic receptor agonist, would improve ICDs.
Methods: We conducted a multicentre trial in five movement disorder departments.
Alzheimers Dement
September 2023
Introduction: The associations between subjective cognitive decline (SCD), cognition, and amyloid were explored across diverse participants in the A4 study.
Methods: Five thousand one hundred and fifty-one non-Hispanic White, 262 non-Hispanic Black, 179 Hispanic-White, and 225 Asian participants completed the Preclinical Alzheimer Cognitive Composite (PACC), self- and study partner-reported Cognitive Function Index (CFI). A subsample underwent amyloid positron emission tomography ( F-florbetapir) (N = 4384).
Importance: Postmenopausal females represent around 70% of all individuals with Alzheimer disease. Previous literature shows elevated levels of tau in cognitively unimpaired postmenopausal females compared with age-matched males, particularly in the setting of high β-amyloid (Aβ). The biological mechanisms associated with higher tau deposition in female individuals remain elusive.
View Article and Find Full Text PDFDepression is one of the most frequent and burdensome non-motor symptoms in Parkinson's disease (PD), across all stages. Even when its severity is mild, PD depression has a great impact on quality of life for these patients and their caregivers. Accordingly, accurate diagnosis, supported by validated scales, identification of risk factors, and recognition of motor and non-motor symptoms comorbid to depression are critical to understanding the neurobiology of depression, which in turn determines the effectiveness of dopaminergic drugs, antidepressants and non-pharmacological interventions.
View Article and Find Full Text PDFIn this one-year prospective study, Parkinson's disease (PD) patients with or without mania following STN-DBS were compared to investigate risk and etiological factors, clinical management and consequences. Eighteen (16.2%) out of 111 consecutive PD patients developed mania, of whom 17 were males.
View Article and Find Full Text PDFBackground: Parkinson's disease mild cognitive impairment (PD-MCI) is frequent and heterogenous. There is no consensus about its influence on subthalamic deep brain stimulation (STN-DBS) outcomes.
Objective: To determine the prevalence of PD-MCI and its subtypes in candidates to STN-DBS.
Background: Previous studies described a parkinsonian personality characterized as rigid, introverted, and cautious; however, little is known about personality traits in de novo Parkinson's disease (PD) patients and their relationships with motor and neuropsychiatric symptoms.
Objective: To investigate personality in de novo PD and explore its relationship with PD symptoms.
Methods: Using Cloninger's biosocial model, we assessed personality in 193 de novo PD patients.
Background: Deep brain stimulation of the sub-thalamic nucleus (DBS-STN) reduces symptoms in Parkinson's disease (PD) patients with motor fluctuations. However, some patients may not feel ameliorated afterwards, despite an objective motor improvement. It is thus important to find new predictors of patients' quality of life (QoL) amelioration after DBS-STN.
View Article and Find Full Text PDFBackground: Parkinson's disease (PD) is characterized by heterogeneous motor and nonmotor manifestations related to alterations in monoaminergic neurotransmission systems. Nevertheless, the characterization of concomitant dopaminergic and serotonergic dysfunction after different durations of Parkinson's disease, as well as their respective involvement in the expression and severity of neuropsychiatric signs, has gained little attention so far.
Methods: To fill this gap, we conducted a cross-sectional study combining clinical and dual-tracer positron emission tomography (PET) neuroimaging approaches, using radioligands of dopamine ([ C]-N-(3-iodoprop-2E-enyl)-2-beta-carbomethoxy-3-beta-(4-methylphenyl)-nortropane) ([ C]PE2I) and serotonin ([ C]-N,N-dimethyl-2-(-2-amino-4-cyanophenylthio)-benzylamine) ([ C]DASB) reuptake, after different durations of Parkinson's disease (ie, in short-disease duration drug-naive de novo (n = 27, 0-2 years-duration), suffering from apathy (n = 14) or not (n = 13); intermediate-disease duration (n = 15, 4-7 years-duration) and long-disease duration, non-demented (n = 15, 8-10 years-duration) patients).