Cohort Analysis of the Association of Delirium Severity With Cerebrospinal Fluid Amyloid-Tau-Neurodegeneration Pathologies

Delirium is associated with cognitive decline and subsequent dementia, and rises in plasma total Tau (tTau) and neurofilament light (NfL), providing links to Amyloid-Tau-Neurodegeneration (ATN) pathophysiology. We investigated whether changes in delirium severity after surgery correlated with changes in cerebrospinal fluid (CSF) ATN biomarkers. Thirty-two thoracic vascular surgical patients were recruited into a prospective biomarker cohort study with assessment of delirium severity and incidence (NCT02926417). CSF (n = 54) and plasma (n = 118) samples were sent for biomarker analysis for tTau, phosphorylated tau-181 (pTau) (plasma n = 53), NfL, and amyloid-β 42/40 ratio (Ab42/40-ratio). The primary outcome was the correlation of preoperative to postoperative change in ATN biomarkers with the highest postoperative Delirium Rating Scale-98 score. CSF and plasma biomarkers all increased postoperatively (all P < .05, n = 13 paired preoperative-postoperative samples). Delirium severity was associated with peak changes in CSF tTau (P = .007, r = 0.710) and pTau (P = .01, r = 0.667) but not NfL (P = .09, rho = 0.491) or Ab42/40-ratio (P = 0.18, rho = 0.394). Sensitivity analysis with exclusion of subjects with putative spinal cord ischaemia shifted the NfL result to significance (P < .001, rho = .847). Our data show that changes in tau and biomarkers of neurodegeneration in the CSF are associated with delirium severity. These data should be considered hypothesis generating and future studies should identify if these changes are robust to confounding

Association between plasma tau and postoperative delirium incidence and severity: a prospective observational study

BACKGROUND: Postoperative delirium is associated with increases in the neuronal injury biomarker, neurofilament light (NfL). Here we tested whether two other biomarkers, glial fibrillary acidic protein (GFAP) and tau, are associated with postoperative delirium. METHODS: A total of 114 surgical patients were recruited into two prospective biomarker cohort studies with assessment of delirium severity and incidence. Plasma samples were sent for biomarker analysis including tau, NfL, and GFAP, and a panel of 10 cytokines. We determined a priori to adjust for interleukin-8 (IL-8), a marker of inflammation, when assessing associations between biomarkers and delirium incidence and severity. RESULTS: GFAP concentrations showed no relationship to delirium. The change in tau from preoperative concentrations to postoperative Day 1 was greater in patients with postoperative delirium (P<0.001) and correlated with delirium severity (ρ=0.39, P<0.001). The change in tau correlated with increases in IL-8 (P<0.001) and IL-10 (P=0.0029). Linear regression showed that the relevant clinical predictors of tau changes were age (P=0.037), prior stroke/transient ischaemic attack (P=0.001), and surgical blood loss (P<0.001). After adjusting for age, sex, preoperative cognition, and change in IL-8, tau remained significantly associated with delirium severity (P=0.026). Using linear mixed effect models, only tau (not NfL or IL-8) predicted recovery from delirium (P<0.001). CONCLUSIONS: The change in plasma tau was associated with delirium incidence and severity, and resolved over time in parallel with delirium features. The impact of this putative perioperative neuronal injury biomarker on long-term cognition merits further investigation. CLINICAL TRIAL REGISTRATION: NCT02926417 and NCT03124303

Duplications in RB1CC1 are associated with schizophrenia; identification in large European sample sets

Schizophrenia (SCZ) is a severe and debilitating neuropsychiatric disorder with an estimated heritability of ~80%. Recently, de novo mutations, identified by next-generation sequencing (NGS) technology, have been suggested to contribute to the risk of developing SCZ. Although these studies show an overall excess of de novo mutations among patients compared with controls, it is not easy to pinpoint specific genes hit by de novo mutations as actually involved in the disease process. Importantly, support for a specific gene can be provided by the identification of additional alterations in several independent patients. We took advantage of existing genome-wide single-nucleotide polymorphism data sets to screen for deletions or duplications (copy number variations, CNVs) in genes previously implicated by NGS studies. Our approach was based on the observation that CNVs constitute part of the mutational spectrum in many human disease-associated genes. In a discovery step, we investigated whether CNVs in 55 candidate genes, suggested from NGS studies, were more frequent among 1637 patients compared with 1627 controls. Duplications in RB1CC1 were overrepresented among patients. This finding was followed-up in large, independent European sample sets. In the combined analysis, totaling 8461 patients and 112 871 controls, duplications in RB1CC1 were found to be associated with SCZ (P=1.29 × 10−5; odds ratio=8.58). Our study provides evidence for rare duplications in RB1CC1 as a risk factor for SCZ

Treatment options for severe hypertriglyceridemia (SHTG): the role of apheresis

Hypertriglyceridemia is associated with a number of severe diseases such as acute pancreatitis and coronary artery disease. In severe hypertriglyceridemia (SHTG, triglycerides > 1,000 mg/dL), rapid lowering of plasma triglycerides (TG) has to be achieved. Treatment regimes include nutritional intervention, the use of antihyperlipidemic drugs, and therapeutic apheresis. Apheretic treatment is indicated in medical emergencies such as hypertriglyceridemic pancreatitis

Role of lipid apheresis in changing times

During the last decades, LDL-apheresis was established as an extracorporeal treatment option for patients with severe heterozygous or homozygous familial hypercholesterolemia (FH) that is resistant to conventional treatment strategies such as diet, drugs, and changes in lifestyle. Nearly half a century ago, the first LDL-apheresis treatment was performed by plasma exchange in a child with homozygous FH

Silencing Nociceptor Neurons Reduces Allergic Airway Inflammation

Lung nociceptors initiate cough and bronchoconstriction. To elucidate if these fibers also contribute to allergic airway inflammation, we stimulated lung nociceptors with capsaicin and observed increased neuropeptide release and immune cell infiltration. In contrast, ablating Nav1.8(+) sensory neurons or silencing them with QX-314, a charged sodium channel inhibitor that enters via large-pore ion channels to specifically block nociceptors, substantially reduced ovalbumin- or house-dust-mite-induced airway inflammation and bronchial hyperresponsiveness. We also discovered that IL-5, a cytokine produced by activated immune cells, acts directly on nociceptors to induce the release of vasoactive intestinal peptide (VIP). VIP then stimulates CD4(+) and resident innate lymphoid type 2 cells, creating an inflammatory signaling loop that promotes allergic inflammation. Our results indicate that nociceptors amplify pathological adaptive immune responses and that silencing these neurons with QX-314 interrupts this neuro-immune interplay, revealing a potential new therapeutic strategy for asthma

Association of Transcription Factor 4 (TCF4) variants with schizophrenia and intellectual disability

Genome wide association studies (GWAS) have revolutionized the study of complex diseases and have uncovered common genetic variants associated with an increased risk for major psychiatric disorders. A recently published schizophrenia GWAS replicated earlier findings implicating common variants in Transcription factor 4 (TCF4) as susceptibility loci for schizophrenia. By contrast, loss of function TCF4 mutations, although rare, cause Pitt-Hopkins syndrome (PTHS); a disorder characterized by intellectual disability (ID), developmental delay and behavioral abnormalities. TCF4 mutations have also been described in individuals with ID and non-syndromic neurodevelopmental disorders. TCF4 is a member of the basic helix-loop-helix (bHLH) family of transcription factors that regulate gene expression at E-box-containing promoters and enhancers. Accordingly, TCF4 has an important role during brain development and can interact with a wide array of transcriptional regulators including some proneural factors. TCF4 may, therefore, participate in the transcriptional networks that regulate the maintenance and differentiation of distinct cell types during brain development. Here, we review the role of TCF4 variants in the context of several distinct brain disorders associated with impaired cognition

Rates, distribution and implications of postzygotic mosaic mutations in autism spectrum disorder

We systematically analyzed postzygotic mutations (PZMs) in whole-exome sequences from the largest collection of trios (5,947) with autism spectrum disorder (ASD) available, including 282 unpublished trios, and performed resequencing using multiple independent technologies. We identified 7.5% of de novo mutations as PZMs, 83.3% of which were not described in previous studies. Damaging, nonsynonymous PZMs within critical exons of prenatally expressed genes were more common in ASD probands than controls (P < 1 Ã 10-6), and genes carrying these PZMs were enriched for expression in the amygdala (P = 5.4 Ã 10-3). Two genes (KLF16 and MSANTD2) were significantly enriched for PZMs genome-wide, and other PZMs involved genes (SCN2A, HNRNPU and SMARCA4) whose mutation is known to cause ASD or other neurodevelopmental disorders. PZMs constitute a significant proportion of de novo mutations and contribute importantly to ASD risk