Publications by authors named "David Cuthbertson"

Challenges in time to event type 1 diabetes (T1D) prevention trial design can yield negative results even for treatments that may actually improve disease pathology. We evaluated whether a binary metabolic end point for 12-month change from baseline to 1 year postrandomization could be useful in T1D prevention trials. This approach detected treatment effects at least as well as standard primary end points with shorter follow-up.

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Objective: To compare the efficacy of abatacept to placebo for the treatment of relapsing, nonsevere granulomatosis with polyangiitis (GPA).

Methods: In this multicenter trial, eligible patients with relapsing, nonsevere GPA were randomized to receive abatacept 125 mg subcutaneously once a week or placebo, both together with prednisone 30 mg/day (or equivalent), tapered and discontinued at week 12. Patients already taking methotrexate, azathioprine, mycophenolate, or leflunomide continued this medication at a stable dose.

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The TrialNet Oral Insulin (OI) prevention trial showed no overall treatment effect, using the diagnosis of type 1 diabetes as an endpoint. A significant delay in onset was only found in a high-risk stratum (termed secondary stratum 1) of participants with low first-phase insulin release (FPIR). Since trials with an endpoint of type 1 diabetes take years to complete, in this post hoc analysis, we assessed whether a novel combination of glucose and C-peptide markers could identify a therapeutic benefit after 1 year of follow-up (trial participants followed for a median 2.

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Objective: To describe the frequency and outcomes associated with self-reported frailty in patients with vasculitis.

Methods: VascStrong is a longitudinal study using the Vasculitis Patient-Powered Research Network, an internet-based cohort of patients with vasculitis. Data collected included patient global assessment (PtGA) and several domains of the Patient-Reported Outcomes Measurement Information System (PROMIS).

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Unlabelled: Since little is known about the disposition index (DI) in autoantibody-positive individuals, we have assessed whether DI has a similar association between insulin secretion and sensitivity to the association observed in other populations. In TrialNet Pathway to Prevention (TNPTP; n = 6,620) and Diabetes Prevention Trial-Type 1 (DPT-1; n = 704) study participants, two secretion-sensitivity pairs, each representing a DI, were analyzed cross-sectionally at baseline: area under the curve (AUC) C-peptide/AUC glucose (AUC ratio) and Matsuda index (MI) from TNPTP oral glucose tolerance tests (oral DI), first-phase insulin response (FPIR), and 1 / fasting insulin (1/FI) from DPT-1 from intravenous glucose tolerance tests (DI). Participants were followed for progression to type 1 diabetes (T1D).

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Aims/hypothesis: Accurate understanding of type 1 diabetes risk is critical for optimisation of counselling, monitoring and interventions, yet even within established staging classifications, individual time to clinical disease varies. Previous work has associated IA-2A positivity with increased type 1 diabetes progression but a comprehensive assessment of the impact of screening for IA-2A positivity across the natural history of autoantibody positivity has not been performed. We asked whether IA-2A would consistently be associated with higher risk of progression within and across established stages of type 1 diabetes in a large natural history study.

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Article Synopsis
  • The study investigated a glucose fraction that operates independently of insulin secretion in individuals positive for diabetes-related autoantibodies.
  • It utilized data from two major trials, analyzing the relationship between the glucose response and insulin levels through linear regression.
  • Findings revealed that this independent glucose fraction (iAUCGLU) significantly contributes to the rise in blood sugar levels in impaired glucose tolerance and is a stronger predictor for this condition than for type 1 diabetes (T1D).
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Aims/hypothesis: Many studies of type 1 diabetes pathogenesis focus on individuals with high-risk HLA haplotypes. We tested the hypothesis that, among islet autoantibody-positive individuals, lacking HLA-DRB1*04-DQA1*03-DQB1*0302 (HLA-DR4-DQ8) and/or HLA-DRB1*0301-DQA1*0501-DQB1*0201 (HLA-DR3-DQ2) is associated with phenotypic differences, compared with those who have these high-risk HLA haplotypes.

Methods: We classified autoantibody-positive relatives of individuals with type 1 diabetes into four groups based on having both HLA-DR4-DQ8 and HLA-DR3-DQ2 (DR3/DR4; n=1263), HLA-DR4-DQ8 but not HLA-DR3-DQ2 (DR4/non-DR3; n=2340), HLA-DR3-DQ2 but not HLA-DR4-DQ8 (DR3/non-DR4; n=1607) and neither HLA-DR3-DQ2 nor HLA-DR4-DQ8 (DRX/DRX; n=1294).

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Aims/hypothesis: We aimed to analyse TrialNet Anti-CD3 Prevention (TN10) data using oral minimal model (OMM)-derived indices to characterise the natural history of stage 2 type 1 diabetes in placebo-treated individuals, to describe early metabolic responses to teplizumab and to explore the predictive capacity of OMM measures for disease-free survival rate.

Methods: OMM-estimated insulin secretion, sensitivity and clearance and the disposition index were evaluated at baseline and at 3, 6 and 12 months post randomisation in placebo- and teplizumab-treated groups, and, within each group, in slow- and rapid-progressors (time to stage 3 disease >2 or 2 years). OMM metrics were also compared with the standard AUC C-peptide.

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Article Synopsis
  • - This study aimed to find plasma protein patterns that can differentiate between active and inactive giant cell arteritis (GCA) patients and healthy controls by analyzing their plasma samples.
  • - Researchers collected samples from 30 GCA patients and 30 matched controls, using a high-tech proteomics assay that evaluated over 7000 proteins, identifying significant differences in protein levels related to disease activity.
  • - The results revealed specific proteins linked to GCA and showed strong potential for using machine learning models to identify different disease states, although distinguishing between active and inactive states in the same patient was challenging.
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Background: The Trial to Reduce IDDM in the Genetically at Risk (TRIGR) (NCT00179777) found no difference type 1 diabetes risk between hydrolyzed and regular infant formula. However, cow milk consumption during childhood is consistently linked to type 1 diabetes risk in prospective cohort studies.

Objectives: Our primary aim was to study whether humoral immune responses to cow milk and cow milk consumption are associated with type 1 diabetes in TRIGR children.

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Objectives: To evaluate damage and clinical characteristics associated with damage in Takayasu's arteritis (TAK).

Methods: Patients with TAK enrolled in a multicentre, prospective, observational study underwent standardized damage assessment every 6 months using the Vasculitis Damage Index (VDI) and the Large-Vessel Vasculitis Index of Damage (LVVID).

Results: The study included 236 patients with TAK: 92% female, 81% Caucasian; median (25th, 75th percentile) disease duration = 2.

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Objective: Mixed-meal tolerance test-stimulated area under the curve (AUC) C-peptide at 12-24 months represents the primary end point for nearly all intervention trials seeking to preserve β-cell function in recent-onset type 1 diabetes. We hypothesized that participant benefit might be detected earlier and predict outcomes at 12 months posttherapy. Such findings would support shorter trials to establish initial efficacy.

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Article Synopsis
  • The study gathered data on 358 patients with polyarteritis nodosa (PAN) from nine countries, analyzing demographics, clinical features, and survival rates over 30 years.
  • Findings showed common symptoms such as constitutional issues, skin lesions, joint pain, and neurological problems, with a significant relapse rate of 48.5% during an average follow-up of nearly five years.
  • Survival rates for systemic PAN showed a decline over time, with important risk factors for mortality including older age, high serum creatinine levels, and involvement of the gastrointestinal system or central nervous system.
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Context: Metabolic measures are frequently used to predict type 1 diabetes (T1D) and to understand effects of disease-modifying therapies.

Objective: Compare metabolic endpoints for their ability to detect preventive treatment effects and predict T1D.

Methods: Six-month changes in metabolic endpoints were assessed for (1) detecting treatment effects by comparing placebo and treatment arms from the randomized controlled teplizumab prevention trial, a multicenter clinical trial investigating 14-day intravenous teplizumab infusion and (2) predicting T1D in the TrialNet Pathway to Prevention natural history study.

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Introduction: Although the alternative complement pathway has been implicated in the pathogenesis of antineutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis (AAV), the specific nature of its involvement is unclear. This study measured levels of urine and plasma complement fragment Ba at multiple time points in a group of patients with AAV.

Methods: The complement fragment Ba was measured by enzyme-linked immunosorbent assay in serial urine and plasma samples from 21 patients with AAV who developed a renal flare, 19 who developed a nonrenal flare, and 20 in long-term remission.

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Aim/hypothesis: We assessed whether HOMA-IR and the Matsuda Index are associated with transitions through stages of type 1 diabetes.

Methods: Autoantibody (AAb)-positive relatives of individuals with type 1 diabetes (n=6256) from the TrialNet Pathway to Prevention were studied. Associations of indicators of insulin resistance (HOMA-IR) and insulin sensitivity (Matsuda Index) with BMI percentile (BMIp) and age were assessed with adjustments for measures of insulin secretion, Index60 and insulinogenic index (IGI).

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Markers of extracellular mitochondria are present in giant cell arteritis (GCA) patients. However, their role in promoting inflammation and platelet activation is no known. To investigate this, isolated mitochondria were opsonized with plasma from GCA patients or healthy individuals and incubated with peripheral blood mononuclear cells (PBMCs) or platelets and assessed for inflammatory cytokine production and platelet activation.

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Objective: This study examined the relationship between age at diagnosis and disease characteristics and damage in patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV).

Methods: Analysis of a prospective longitudinal cohort of patients with granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic GPA (EGPA) in the Vasculitis Clinical Research Consortium (2013-2021). Disease cohorts were divided by age at diagnosis (years): children (<18), young adults (18-40), middle-aged adults (41-65), and older adults (>65).

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Background: The most reliable and meaningful approach for inclusion of patient-reported outcomes (PROs) in the evaluation of real-world clinical effectiveness of biologics in the treatment of autoimmune diseases is u ncertain. This study aimed to assess and compare the proportions of patients who had abnormalities in PROs measuring important general health domains at the initiation of treatment with biologics, as well as the effects of baseline abnormalities on subsequent improvement.

Methods: PROs were collected for patient participants with inflammatory arthritis, inflammatory bowel disease, and vasculitis using Patient-Reported Outcomes Measurement Information System instruments.

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Objective: Metabolic zones were developed to characterize heterogeneity of individuals with islet autoantibodies.

Research Design And Methods: Baseline 2-h oral glucose tolerance test data from 6,620 TrialNet Pathway to Prevention Study (TNPTP) autoantibody-positive participants (relatives of individuals with type 1 diabetes) were used to form 25 zones from five area under the curve glucose (AUCGLU) rows and five area under the curve C-peptide (AUCPEP) columns. Zone phenotypes were developed from demographic, metabolic, autoantibody, HLA, and risk data.

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Article Synopsis
  • This study measured levels of neutrophil extracellular traps (NETs) in the plasma of healthy individuals and various patients with different types of vasculitis to understand their role in disease activity.
  • It found that NET levels were significantly higher during active disease phases in patients with granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), Takayasu's arteritis (TAK), and giant cell arteritis (GCA), indicating a link between NETs and disease severity.
  • Additionally, the study suggested that increased levels of the thrombospondin-1 (TSP-1) protein were associated with NET formation, highlighting the potential of targeting NETs in developing new treatments for these
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Objective: Vitamin D might participate in the pathogenesis of several immune-mediated diseases, but few related data are available for ANCA-associated vasculitis (AAV). In this study, we analysed the association between vitamin D status and disease in patients with AAV.

Methods: Serum levels of 25(OH)D were measured in 125 randomly selected patients with AAV [granulomatosis with polyangiitis ( = 50), eosinophilic granulomatosis with polyangiitis ( = 50) or microscopic polyangiitis ( = 25)] enrolled in the Vasculitis Clinical Research Consortium Longitudinal Studies at the time of enrolment and a subsequent relapse visit.

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Objectives: ANCA-associated vasculitis (AAV) is a group of multisystem diseases that can have several ocular manifestations. There are published data on ocular manifestations of granulomatosis with polyangiitis (GPA), but few for eosinophilic granulomatosis with polyangiitis (EGPA) or microscopic polyangiitis (MPA). There is little information concerning chronicity, complications, and association with other cranial manifestations of AAV.

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Background & Aims: Nutrient status may affect the risk of microbial infections and play a role in modulating the immune response against such infections. The aim of this study was to determine whether serum 25-hydroxyvitamin D [25(OH)D] and serum fatty acids in infancy are associated with microbial infections by the age of 18 months.

Methods: Altogether 576 newborn infants from Trial to Reduce IDDM in the Genetically at Risk (TRIGR) born between 2002 and 2007 were included.

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