Browsing by Author "Krischer, Jeffrey"

Now showing 1 - 4 of 4
  • Thumbnail Image
    Item
    Barriers to Screening: An Analysis of Factors Impacting Screening for Type 1 Diabetes Prevention Trials
    (Oxford University Press, 2023-01-11) Kinney, Mara; You, Lu; Sims, Emily K.; Wherrett, Diane; Schatz, Desmond; Lord, Sandra; Krischer, Jeffrey; Russell, William E.; Gottlieb, Peter A.; Libman, Ingrid; Buckner, Jane; DiMeglio, Linda A.; Herold, Kevan C.; Steck, Andrea K.; Pediatrics, School of Medicine
    Context: Participants with stage 1 or 2 type 1 diabetes (T1D) qualify for prevention trials, but factors involved in screening for such trials are largely unknown. Objective: To identify factors associated with screening for T1D prevention trials. Methods: This study included TrialNet Pathway to Prevention participants who were eligible for a prevention trial: oral insulin (TN-07, TN-20), teplizumab (TN-10), abatacept (TN-18), and oral hydroxychloroquine (TN-22). Univariate and multivariate logistic regression models were used to examine participant, site, and study factors at the time of prevention trial accrual. Results: Screening rates for trials were: 50% for TN-07 (584 screened/1172 eligible), 9% for TN-10 (106/1249), 24% for TN-18 (313/1285), 17% for TN-20 (113/667), and 28% for TN-22 (371/1336). Younger age and male sex were associated with higher screening rates for prevention trials overall and for oral therapies. Participants with an offspring with T1D showed lower rates of screening for all trials and oral drug trials compared with participants with other first-degree relatives as probands. Site factors, including larger monitoring volume and US site vs international site, were associated with higher prevention trial screening rates. Conclusions: Clear differences exist between participants who screen for prevention trials and those who do not screen and between the research sites involved in prevention trial screening. Participant age, sex, and relationship to proband are significantly associated with prevention trial screening in addition to key site factors. Identifying these factors can facilitate strategic recruitment planning to support rapid and successful enrollment into prevention trials.
  • Thumbnail Image
    Item
    Clinical Features and Associated Likelihood of Primary Ciliary Dyskinesia in Children and Adolescents
    (American Thoracic Society, 2016-08) Leigh, Margaret W.; Ferkol, Thomas W.; Davis, Stephanie D.; Lee, Hye-Seung; Rosenfeld, Margaret; Dell, Sharon D.; Sagel, Scott D.; Milla, Carlos; Olivier, Kenneth N.; Sullivan, Kelli M.; Zariwala, Maimoona A.; Pittman, Jessica E.; Shapiro, Adam J.; Carson, Johnny L.; Krischer, Jeffrey; Hazucha, Milan J.; Knowles, Michael R.; Pediatrics, School of Medicine
    Rationale: Primary ciliary dyskinesia (PCD), a genetically heterogeneous, recessive disorder of motile cilia, is associated with distinct clinical features. Diagnostic tests, including ultrastructural analysis of cilia, nasal nitric oxide measurements, and molecular testing for mutations in PCD genes, have inherent limitations., Objectives: To define a statistically valid combination of systematically defined clinical features that strongly associates with PCD in children and adolescents., Methods: Investigators at seven North American sites in the Genetic Disorders of Mucociliary Clearance Consortium prospectively and systematically assessed individuals (aged 0–18 yr) referred due to high suspicion for PCD. The investigators defined specific clinical questions for the clinical report form based on expert opinion. Diagnostic testing was performed using standardized protocols and included nasal nitric oxide measurement, ciliary biopsy for ultrastructural analysis of cilia, and molecular genetic testing for PCD-associated genes. Final diagnoses were assigned as “definite PCD” (hallmark ultrastructural defects and/or two mutations in a PCD-associated gene), “probable/possible PCD” (no ultrastructural defect or genetic diagnosis, but compatible clinical features and nasal nitric oxide level in PCD range), and “other diagnosis or undefined.” Criteria were developed to define early childhood clinical features on the basis of responses to multiple specific queries. Each defined feature was tested by logistic regression. Sensitivity and specificity analyses were conducted to define the most robust set of clinical features associated with PCD., Measurements and Main Results: From 534 participants 18 years of age and younger, 205 were identified as having “definite PCD” (including 164 with two mutations in a PCD-associated gene), 187 were categorized as “other diagnosis or undefined,” and 142 were defined as having “probable/possible PCD.” Participants with “definite PCD” were compared with the “other diagnosis or undefined” group. Four criteria-defined clinical features were statistically predictive of PCD: laterality defect; unexplained neonatal respiratory distress; early-onset, year-round nasal congestion; and early-onset, year-round wet cough (adjusted odds ratios of 7.7, 6.6, 3.4, and 3.1, respectively). The sensitivity and specificity based on the number of criteria-defined clinical features were four features, 0.21 and 0.99, respectively; three features, 0.50 and 0.96, respectively; and two features, 0.80 and 0.72, respectively., Conclusions: Systematically defined early clinical features could help identify children, including infants, likely to have PCD., Clinical trial registered with ClinicalTrials.gov (NCT00323167).
  • Thumbnail Image
    Item
    Risk of celiac disease autoimmunity is modified by interactions between CD247 and environmental exposures
    (Springer Nature, 2024-10-26) Eurén, Anna; Lynch, Kristian; Lindfors, Katri; Parikh, Hemang; Koletzko, Sibylle; Liu, Edwin; Akolkar, Beena; Hagopian, William; Krischer, Jeffrey; Rewers, Marian; Toppari, Jorma; Ziegler, Anette; Agardh, Daniel; Kurppa, Kalle; TEDDY Study Group; Pediatrics, School of Medicine
    Season of birth, viral infections, HLA haplogenotypes and non-HLA variants are implicated in the development of celiac disease and celiac disease autoimmunity, suggesting a combined role of genes and environmental exposures. The aim of the study was to further decipher the biological pathways conveying the season of birth effect in celiac disease autoimmunity to gain novel insights into the early pathogenesis of celiac disease. Interactions between season of birth, genetics, and early-life environmental factors on the risk of celiac autoimmunity were investigated in the multicenter TEDDY birth cohort study. Altogether 6523 genetically predisposed children were enrolled to long-term follow-up with prospective sampling and data collection at six research centers in the USA, Germany, Sweden and Finland. Celiac disease autoimmunity was defined as positive tissue transglutaminase antibodies in two consecutive serum samples. There was a significant season of birth effect on the risk of celiac autoimmunity. The effect was dependent on polymorphisms in CD247 gene encoding for CD3ζ chain of TCR-CD3 complex. In particular, children with major alleles for SNP rs864537A > G, in CD247 (AA genotype) had an excess risk of celiac autoimmunity when born March-August as compared to other months. The interaction of CD247 with season of birth on autoimmunity risk was accompanied by interactions with febrile infections between the ages of 3-6 months. Considering the important role of TCR-CD3 complex in the adaptive immune response and our findings here, CD247 variants and their possible effect of subgroups in autoimmunity development could be of interest in the design of future gene-environment studies of celiac disease.
  • Thumbnail Image
    Item
    Who Is Enrolling? The Path to Monitoring in Type 1 Diabetes TrialNet’s Pathway to Prevention
    (American Diabetes Association, 2019-12) Sims, Emily K.; Geyer, Susan; Bennett Johnson, Suzanne; Libman, Ingrid; Jacobsen, Laura M.; Boulware, David; Rafkin, Lisa E.; Matheson, Della; Atkinson, Mark A.; Rodriguez, Henry; Spall, Maria; Elding Larsson, Helena; Wherrett, Diane K.; Greenbaum, Carla J.; Krischer, Jeffrey; DiMeglio, Linda A.; Pediatrics, School of Medicine
    Objective: To better understand potential facilitators of individual engagement in type 1 diabetes natural history and prevention studies through analysis of enrollment data in the TrialNet Pathway to Prevention (PTP) study. Research design and methods: We used multivariable logistic regression models to examine continued engagement of eligible participants at two time points: 1) the return visit after screening to confirm an initial autoantibody-positive (Ab+) test result and 2) the initial oral glucose tolerance test (OGTT) for enrollment into the monitoring protocol. Results: Of 5,387 subjects who screened positive for a single autoantibody (Ab), 4,204 (78%) returned for confirmatory Ab testing. Younger age was associated with increased odds of returning for Ab confirmation (age <12 years vs. >18 years: odds ratio [OR] 2.12, P < 0.0001). Racial and ethnic minorities were less likely to return for confirmation, particularly nonwhite non-Hispanic (OR 0.50, P < 0.0001) and Hispanic (OR 0.69, P = 0.0001) relative to non-Hispanic white subjects. Of 8,234 subjects, 5,442 (66%) were identified as eligible to be enrolled in PTP OGTT monitoring. Here, younger age and identification as multiple Ab+ were associated with increased odds of returning for OGTT monitoring (age <12 years vs. >18 years: OR 1.43, P < 0.0001; multiple Ab+: OR 1.36, P < 0.0001). Parents were less likely to enroll into monitoring than other relatives (OR 0.78, P = 0.004). Site-specific factors, including site volume and U.S. site versus international site, were also associated with differences in rates of return for Ab+ confirmation and enrollment into monitoring. Conclusions: These data confirm clear differences between successfully enrolled populations and those lost to follow-up, which can serve to identify strategies to increase ongoing participation.