Plasma MIA, CRP, and Albumin Predict Cognitive Decline in Parkinson's Disease.

OBJECTIVE: Using a multi-cohort, discovery-replication-validation design, we sought new plasma biomarkers that predict which individuals with Parkinson's disease (PD) will experience cognitive decline. METHODS: In 108 discovery cohort PD individuals and 83 replication cohort PD individuals, we measured 940 plasma proteins on an aptamer-based platform. Using proteins associated with subsequent cognitive decline in both cohorts, we trained a logistic regression model to predict which patients with PD showed fast (> = 1 point drop/year on Montreal Cognitive Assessment [MoCA]) versus slow (< 1 point drop/year on MoCA) cognitive decline in the discovery cohort, testing it in the replication cohort. We developed alternate assays for the top 3 proteins and confirmed their ability to predict cognitive decline - defined by change in MoCA or development of incident mild cognitive impairment (MCI) or dementia - in a validation cohort of 118 individuals with PD. We investigated the top plasma biomarker for causal influence by Mendelian randomization (MR). RESULTS: A model with only 3 proteins (melanoma inhibitory activity protein [MIA], C-reactive protein [CRP], and albumin) separated fast versus slow cognitive decline subgroups with an area under the curve (AUC) of 0.80 in the validation cohort. The individuals with PD in the validation cohort in the top quartile of risk for cognitive decline based on this model were 4.4 times more likely to develop incident MCI or dementia than those in the lowest quartile. Genotypes at MIA single nucleotide polymorphism (SNP) rs2233154 associated with MIA levels and cognitive decline, providing evidence for MIA's causal influence. CONCLUSIONS: An easily obtained plasma-based predictor identifies individuals with PD at risk for cognitive decline. MIA may participate causally in development of cognitive decline. ANN NEUROL 2022;92:255-269.

TMEM106B Effect on cognition in Parkinson disease and frontotemporal dementia.

OBJECTIVE: Common variants near TMEM106B associate with risk of developing frontotemporal dementia (FTD). Emerging evidence suggests a role for TMEM106B in neurodegenerative processes beyond FTD. We evaluate the effect of TMEM106B genotype on cognitive decline across multiple neurogenerative diseases. METHODS: We longitudinally followed 870 subjects with diagnoses of Parkinson disease (PD; n = 179), FTD (n = 179), Alzheimer disease (AD; n = 300), memory-predominant mild cognitive impairment (MCI; n = 75), or neurologically normal control subjects (NC; n = 137) at the University of Pennsylvania (UPenn). All participants had annual Mini-Mental State Examination (MMSE; median follow-up duration = 3.0 years) and were genotyped at TMEM106B index single nucleotide polymorphism rs1990622. Genotype effects on cognition were confirmed by extending analyses to additional cognitive instruments (Mattis Dementia Rating Scale-2 [DRS-2] and Montreal Cognitive Assessment [MoCA]) and to an international validation cohort (Parkinson's Progression Markers Initiative [PPMI], N = 371). RESULTS: The TMEM106B rs1990622T allele, linked to increased risk of FTD, associated with greater MMSE decline over time in PD subjects but not in AD or MCI subjects. For FTD subjects, rs1990622T associated with more rapid decrease in MMSE only under the minor-allele, rs1990622C , dominant model. Among PD patients, rs1990622T carriers from the UPenn cohort demonstrated more rapid longitudinal decline in DRS-2 scores. Finally, in the PPMI cohort, TMEM106B risk allele carriers demonstrated more rapid longitudinal decline in MoCA scores. INTERPRETATION: Irrespective of cognitive instrument or cohort assessed, TMEM106B acts as a genetic modifier for cognitive trajectory in PD. Our results implicate lysosomal dysfunction in the pathogenesis of cognitive decline in 2 different proteinopathies. ANN NEUROL 2019;85:801-811.

Divergent patterns of TDP-43 and tau pathologies in primary progressive aphasia.

OBJECTIVE: To measure postmortem burden of frontotemporal lobar degeneration (FTLD) with TDP-43 (FTLD-TDP) or tau (FTLD-Tau) proteinopathy across hemispheres in primary progressive aphasia (PPA) using digital histopathology and to identify clinicopathological correlates of these distinct proteinopathies. METHODS: In an autopsy cohort of PPA (FTLD-TDP = 13, FTLD-Tau = 14), we analyzed laterality and regional distribution of postmortem pathology, quantified using a validated digital histopathological approach, in available brain tissue from up to 8 cortical regions bilaterally. We related digital pathology to antemortem structural neuroimaging and specific clinical language features. RESULTS: Postmortem cortical pathology was left-lateralized in both FTLD-TDP (beta = -0.15, standard error [SE] = 0.05, p = 0.007) and FTLD-Tau (beta = -0.09, SE = 0.04, p = 0.015), but the degree of lateralization decreased with greater overall dementia severity before death (beta = -8.18, SE = 3.22, p = 0.015). Among 5 core pathology regions sampled, we found greatest pathology in left orbitofrontal cortex (OFC) in FTLD-TDP, which was greater than in FTLD-Tau (F = 47.07, df = 1,17, p < 0.001), and in left midfrontal cortex (MFC) in FTLD-Tau, which was greater than in FTLD-TDP (F = 19.34, df = 1,16, p < 0.001). Postmortem pathology was inversely associated with antemortem magnetic resonance imaging cortical thickness (beta = -0.04, SE = 0.01, p = 0.007) in regions matching autopsy sampling. Irrespective of PPA syndromic variant, single-word comprehension impairment was associated with greater left OFC pathology (t = -3.72, df = 10.72, p = 0.004) and nonfluent speech with greater left MFC pathology (t = -3.62, df = 12.00, p = 0.004) among the 5 core pathology regions. INTERPRETATION: In PPA, FTLD-TDP and FTLD-Tau have divergent anatomic distributions of left-lateralized postmortem pathology that relate to antemortem structural imaging and distinct language deficits. Although other brain regions may be implicated in neural networks supporting these complex language measures, our observations may eventually help to improve antemortem diagnosis of neuropathology in PPA. Ann Neurol 2019;85:630-643.

Ante mortem cerebrospinal fluid tau levels correlate with postmortem tau pathology in frontotemporal lobar degeneration.

OBJECTIVE: To test the hypotheses that (1) antemortem cerebrospinal fluid (CSF) tau levels correlate with postmortem tau pathology in frontotemporal lobar degeneration (FTLD) and (2) tauopathy patients have higher phosphorylated-tau levels compared to transactivation response element DNA-binding protein 43 (TDP-43) proteinopathy patients while accounting for Alzheimer's disease (AD) copathology. METHODS: Patients had autopsy-confirmed FTLD with tauopathy (n = 31), TDP-43 proteinopathy (n = 49), or AD (n = 26) with antemortem CSF. CSF tau levels were compared between groups and correlated with digital histology measurement of postmortem tau pathology averaged from three cerebral regions (angular gyrus, mid-frontal cortex, and anterior cingulate gyrus). Multivariate linear regression tested the association of ante mortem CSF tau levels with postmortem tau pathology adjusting for demographics. RESULTS: Multivariate regression found an independent association of ante mortem CSF phosphorylated tau levels with postmortem cerebral tau pathology in FTLD (Beta = 1.3; 95% confidence interval = 0.2-2.4; p < 0.02). After excluding patients with coincident AD-associated tau pathology accompanying sporadic FTLD, we found lower CSF phosphorylated tau levels in the TDP-43 group (median = 7.4pg/ml; interquartile range [IQR] = 6.0, 12.3; n = 26) compared to the tauopathy group (median = 12.5pg/ml; IQR = 10.7, 15.0; n = 23; Z = 2.6; p < 0.01). INTERPRETATION: CSF phosphorylated-tau levels are positively associated with cerebral tau burden in FTLD. In vivo detection of AD copathology in sporadic FTLD patients may help stratify clinical cohorts with pure neuropathology in which low CSF phosphorylated-tau levels may have diagnostic utility to distinguish TDP-43 proteinopathy from tauopathy. Autopsy-confirmed samples are critical for FTLD biomarker development and validation. Ann Neurol 2017;82:247-258.

Effects of the Insulin Sensitizer Metformin in Alzheimer Disease: Pilot Data From a Randomized Placebo-controlled Crossover Study.

Epidemiological studies have identified a robust association between type II diabetes mellitus and Alzheimer disease (AD), and neurobiological studies have suggested the presence of central nervous system insulin resistance in individuals with AD. Given this association, we hypothesized that the central nervous system-penetrant insulin-sensitizing medication metformin would be beneficial as a disease-modifying and/or symptomatic therapy for AD, and conducted a placebo-controlled crossover study of its effects on cerebrospinal fluid (CSF), neuroimaging, and cognitive biomarkers. Twenty nondiabetic subjects with mild cognitive impairment or mild dementia due to AD were randomized to receive metformin then placebo for 8 weeks each or vice versa. CSF and neuroimaging (Arterial Spin Label MRI) data were collected for biomarker analyses, and cognitive testing was performed. Metformin was found to be safe, well-tolerated, and measureable in CSF at an average steady-state concentration of 95.6 ng/mL. Metformin was associated with improved executive functioning, and trends suggested improvement in learning/memory and attention. No significant changes in cerebral blood flow were observed, though post hoc completer analyses suggested an increase in orbitofrontal cerebral blood flow with metformin exposure. Further study of these findings is warranted.

A randomised trial of electro-acupuncture for arthralgia related to aromatase inhibitor use.

BACKGROUND: Arthralgia is a common and debilitating side-effect experienced by breast cancer patients receiving aromatase inhibitors (AIs) and often results in premature drug discontinuation. METHODS: We conducted a randomised controlled trial of electro-acupuncture (EA) as compared to waitlist control (WLC) and sham acupuncture (SA) in postmenopausal women with breast cancer who self-reported arthralgia attributable to AIs. Acupuncturists performed 10 EA/SA treatments over 8 weeks using a manualised protocol with 2 Hz electro-stimulation delivered by a TENS unit. Acupuncturists administered SA using Streitberger (non-penetrating) needles at non-traditional acupuncture points without electro-stimulation. The primary end-point was pain severity by Brief Pain Inventory (BPI) between EA and WLC at Week 8; durability of response at Week 12 and comparison of EA to SA were secondary aims. FINDINGS: Of the 67 randomly assigned patients, mean reduction in pain severity was greater in the EA group than in the WLC group at Week 8 (-2.2 versus -0.2, p=0.0004) and at Week 12 (-2.4 versus -0.2, p<0.0001). Pain-related interference measured by BPI also improved in the EA group compared to the WLC group at both Week 8 (-2.0 versus 0.2, p=0.0006) and Week 12 (-2.1 versus -0.1, p=0.0034). SA produced a magnitude of change in pain severity and pain-related interference at Week 8 (-2.3, -1.5 respectively) and Week 12 (-1.7, -1.3 respectively) similar to that of EA. Participants in both EA and SA groups reported few minor adverse events. INTERPRETATIONS: Compared to usual care, EA produced clinically important and durable improvement in arthralgia related to AIs in breast cancer patients, and SA had a similar effect. Both EA and SA were safe.

Long-Term Chamomile Therapy of Generalized Anxiety Disorder: A Study Protocol for a Randomized, Double-Blind, Placebo- Controlled Trial.

BACKGROUND: Anxiety symptoms are among the most common reasons for consumers to use Complementary and Alternative Medicine (CAM) therapy. Although many botanicals have been proposed as putative remedies for anxiety symptoms, there has been a paucity of controlled trials of these remedies. A preliminary study of the anxiolytic effect of Chamomile (Matricaria recutita) in humans suggests that chamomile may have anxiolytic and antidepressant activity. We now seek to conduct a 5-year randomized, double-blind, placebo-substitution study to examine the short and long-term safety and efficacy of chamomile extract in Generalized Anxiety Disorder (GAD). METHODS/DESIGN: 180 subjects with moderate to severe GAD will receive initial open-label pharmaceutical-grade chamomile extract 500-1,500 mg daily for 8 weeks. Responders to treatment who remain well for an additional 4 weeks of consolidation therapy, will be randomized to double-blind continuation therapy with either chamomile extract 500-1,500 mg daily or placebo for an additional 26 weeks. The primary outcome will be the time to relapse during study continuation therapy in each treatment condition. Secondary outcomes will include the proportion of subjects in each treatment condition who relapse, as well as the proportion of subjects with treatment-emergent adverse events. Quality of life ratings will also be compared between treatment conditions during short and long-term therapy. DISCUSSION: Many individuals with mental disorders decline conventional therapy and seek CAM therapies for their symptoms. Thus, the identification of effective CAM therapy is of relevance to reducing the burden of mental illness. This study builds upon our prior findings of significant superiority of chamomile versus placebo in reducing GAD symptoms. We now extend these preliminary findings by conducting a randomized long-term safety and efficacy study of chamomile in GAD.

Plasma apolipoprotein A1 as a biomarker for Parkinson disease.

OBJECTIVE: To identify plasma-based biomarkers for Parkinson disease (PD) risk. METHODS: In a discovery cohort of 152 PD patients, plasma levels of 96 proteins were measured by multiplex immunoassay; proteins associated with age at PD onset were identified by linear regression. Findings from discovery screening were then assessed in a second cohort of 187 PD patients, using a different technique. Finally, in a third cohort of at-risk, asymptomatic individuals enrolled in the Parkinson's Associated Risk Study (PARS, n = 134), plasma levels of the top candidate biomarker were measured, and dopamine transporter (DAT) imaging was performed, to evaluate the association of plasma protein levels with dopaminergic system integrity. RESULTS: One of the best candidate protein biomarkers to emerge from discovery screening was apolipoprotein A1 (ApoA1; p = 0.001). Low levels of ApoA1 correlated with earlier PD onset, with a 26% decrease in risk of developing PD associated with each tertile increase in ApoA1 (Cox proportional hazards, p < 0.001, hazard ratio = 0.742). The association between plasma ApoA1 levels and age at PD onset was replicated in an independent cohort of PD patients (p < 0.001). Finally, in the PARS cohort of high-risk, asymptomatic subjects, lower plasma levels of ApoA1 were associated with greater putaminal DAT deficit (p = 0.037). INTERPRETATION: Lower ApoA1 levels correlate with dopaminergic system vulnerability in symptomatic PD patients and in asymptomatic individuals with physiological reductions in dopamine transporter density consistent with prodromal PD. Plasma ApoA1 may be a new biomarker for PD risk.

Differential longitudinal decline on the Mini-Mental State Examination in frontotemporal lobar degeneration and Alzheimer disease.

OBJECTIVE: To examine how phenotype affects longitudinal decline on the Mini-Mental State Examination (MMSE) in patients with frontotemporal lobar degeneration (FTLD) and Alzheimer disease (AD). BACKGROUND: The MMSE is the most commonly administered assessment for dementia severity; however, the effects of phenotype on longitudinal MMSE performance in FTLD and AD have not been extensively studied. METHODS: Data from 185 patients diagnosed with AD (n=106) and 3 FTLD (n=79) phenotypes [behavioral variant frontotemporal dementia (bvFTD), nonfluent agrammatic variant of primary progressive aphasia (nfaPPA), and semantic variant PPA (svPPA)] were collected for up to 52 months since initial evaluation. RESULTS: Differential rates of decline were noted in that MMSE scores declined more precipitously for AD and svPPA compared with bvFTD and nfaPPA patients (P=0.001). The absolute 4-year MMSE decline given median baseline MMSE for bvFTD [14.67; 95% confidence interval (CI), 14.63-14.71] and nfaPPA (11.02; 95% CI, 10.98-11.06) were lower than svPPA (22.32; 95% CI, 22.29-22.34) or AD (22.24; 95% CI, 22.22-22.26). CONCLUSIONS: These data suggest that within-group AD and FTLD phenotypes present distinct patterns of longitudinal decline on the MMSE. MMSE may not be adequately sensitive to track disease progression in some phenotypes of FTLD.

Frequency and clinicopathological characteristics of presenilin 1 Gly206Ala mutation in Puerto Rican Hispanics with dementia.

The frequency and clinical and pathological characteristics associated with the Gly206Ala presenilin 1 (PSEN1) mutation in Puerto Rican and non-Puerto Rican Hispanics were evaluated at the University of Pennsylvania's Alzheimer's Disease Center. DNAs from all cohort subjects were genotyped for the Gly206Ala PSEN1 mutation. Carriers and non-carriers with neurodegenerative disease dementias were compared for demographic, clinical, psychometric, and biomarker variables. Nineteen (12.6%) of 151 unrelated subjects with dementia were discovered to carry the PSEN1 Gly206Ala mutation. Microsatellite marker genotyping determined a common ancestral haplotype for all carriers. Carriers were all of Puerto Rican heritage with significantly younger age of onset, but otherwise were clinically and neuropsychologically comparable to those of non-carriers with AD. Three subjects had extensive topographic and biochemical biomarker assessments that were also typical of non-carriers with AD. Neuropathological examination in one subject revealed severe, widespread plaque and tangle pathology without other meaningful disease lesions. The PSEN1 Gly206Ala mutation is notably frequent in unrelated Puerto Rican immigrants with dementia in Philadelphia. Considered together with the increased prevalence and mortality of AD reported in Puerto Rico, these high rates may reflect hereditary risk concentrated in the island which warrants further study.