The Quebec Congenital Heart Disease Registry: A Model of Prospective Databank to Facilitate Research in Congenital Cardiology.

Background: A national registry of congenital heart disease (CHD) would facilitate project initiation, decrease costs, increase statistical power, and avoid duplication. Establishing such registries poses numerous challenges, but the current Canadian research ecosystem in CHD is well positioned to meet them. We assessed the feasibility of building a province-wide CHD registry by automatically identifying people with CHD and extracting their native cardiac anatomy from multiple clinical data sources, without the need for manual data entry. Methods: We designed a CHD registry of all fetuses and children with at least 1 echocardiographic report confirming CHD since 2000. We interfaced the registry with several clinical and echocardiography data sources from all paediatric cardiology programmes in Québec. Results: We extracted 885,287 echocardiogram reports and 70,121 clinical records. We identified CHD in 43,452 children and 4682 fetuses. There were 1128 (2.3%) cases with files in multiple institutions, and patients with more complex CHD were 3 times more likely to be seen in more than 1 institution. So far, the registry has been used to build and link CHD cohorts for 7 distinct projects. Conclusions: We demonstrated the feasibility of a baseline CHD registry in Québec without the need for manual data entry, in which other CHD research projects could be nested. This could serve as a blueprint to expand the registry and to develop an integrated approach where data gathered in caring for patients with CHD serve as data layers that incrementally contribute to a national cohort, for which data remain easily accessible and usable.

Contexte: Un registre national des cardiopathies congénitales (CC) pourrait faciliter le lancement de projets de recherche, en diminuer les coûts, en améliorer la puissance statistique tout en évitant les redondances. La mise en place de tels registres pose de nombreux défis, mais l'écosystème de recherche canadien dans le domaine de la CC est bien placé pour y répondre. Nous avons évalué la faisabilité de la mise en place d'un registre des CC à l'échelle provinciale par l'identification automatique des personnes atteintes de CC et l'extraction de leur anatomie cardiaque native à partir de plusieurs sources de données cliniques, sans nécessiter de saisie manuelle de données. Méthodologie: Nous avons conçu un registre des CC incluant tous les fœtus et les enfants pour qui au moins un rapport d'évaluation électrocardiographique confirmait la présence d'une CC depuis 2000. Le registre a été mis en relation avec plusieurs sources de données cliniques et échocardiographiques provenant de tous les programmes en cardiologie pédiatrique au Québec. Résultats: Nous avons extrait 885 287 rapports d'échocardiographie et 70 121 dossiers cliniques. La présence d'une CC a été établie chez 43 452 enfants et 4 682 fœtus. Dans 1 128 cas (2,3 %), un dossier existait dans plus d'un établissement. Les patients présentant des CC plus complexes étaient 3 fois plus susceptibles d'être suivis dans plus d'un établissement. Jusqu'à présent, le registre a été utilisé pour établir et mettre en relation des cohortes de patients atteints de CC pour sept projets de recherche distincts. Conclusions: Nous avons démontré la faisabilité de la mise en place d'un registre de référence des CC au Québec sans recours à la saisie manuelle de données, dans lequel peuvent se nicher d'autres projets de recherche sur les CC. Notre démarche pourrait servir de prototype pour une expansion du registre et pour une approche d'intégration des données recueillies dans la prestation de soins aux patients atteints de CC, afin de former des couches de données qui s'ajoutent au fur et à mesure à une cohorte nationale, avec des données faciles à obtenir et à utiliser.

Variability in Newborn Screening Across Canada: Spinal Muscular Atrophy and Beyond.

BACKGROUND: Newborn screening (NBS) identifies infants with severe, early-onset diseases, enabling early diagnosis and treatment. In Canada, decisions regarding disease inclusion in NBS programs occur at the provincial level, which leads to variability in patient care. We aimed to determine whether important differences exist in NBS programs across provinces and territories. Given that spinal muscular atrophy (SMA) is the most recent disease added to NBS programs, we hypothesized that its inclusion would show interprovincial variability and be more likely in provinces already screening for a greater number of diseases. METHODS: We conducted a cross-sectional survey of all NBS labs in Canada to understand: 1) what conditions were included in their program; 2) what genetic-based testing was performed and; 3) if SMA was included. RESULTS: All NBS programs (N = 8) responded to this survey by June 2022. There was a 2.5-fold difference in the number of conditions screened (N = 14 vs N = 36) and a 9-fold difference in the number of conditions screened by gene-based testing. Only nine conditions were common to all provincial NBS programs. NBS for SMA was performed in four provinces at the time of our survey, with BC recently becoming the fifth province to add SMA to their NBS on October 1, 2022. Currently, 72% of Canadian newborns are screened for SMA at birth. CONCLUSION: Although healthcare in Canada is universal, its decentralization gives rise to regional differences in NBS programs which creates inequity in the treatment, care, and potential outcomes of affected children across provincial jurisdictions.

Spontaneous resolution of post-hemorrhagic ventricular dilatation in preterm newborns and neurodevelopment.

BACKGROUND: We investigated the temporal evolution of post-hemorrhagic ventricular dilatation (PHVD) and compared neurodevelopmental impairments (NDI) in newborns with (Group 1) spontaneous resolution of PHVD, (Group 2) persistent PHVD without neurosurgical intervention, and (Group 3) progressive PHVD receiving neurosurgical intervention. METHODS: A multicenter retrospective cohort study of newborns born at ≤34 weeks with PHVD (ventricular index [VI] >97th centile for gestational age and anterior horn width [AHW] >6 mm) from 2012 to 2020. Severe NDI was defined as global developmental delay or cerebral palsy GMFCS III-V at 18 months. RESULTS: Of 88 survivors with PHVD, 39% had a spontaneous resolution, 17% had persistent PHVD without intervention, and 44% had progressive PHVD receiving intervention. The median time between PHVD diagnosis and spontaneous resolution was 14.0 days (IQR 6.8-32.3) and between PHVD diagnosis and first neurosurgical intervention was 12.0 days (IQR 7.0-22.0). Group 1 had smaller median maximal VI (1.8, 3.4, 11.1 mm above p97; p < 0.001) and AHW (7.2, 10.8, 20.3 mm; p < 0.001) than Groups 2 and 3. Neurodevelopmental outcome data were available for 82% of survivors. Group 1 had reduced severe NDI compared to Group 3 (15% vs 66%; p < 0.001). CONCLUSION: Newborns with PHVD without spontaneous resolution are at higher risk for impairments despite neurosurgical interventions, which may be due to larger ventricular dilatation. IMPACT: The natural evolution of post-hemorrhagic ventricular dilatation (PHVD) and developmental implications of spontaneous resolution are not well established. In this study, approximately one in three newborns with PHVD experienced spontaneous resolution and this subset of newborns had reduced rates of neurodevelopmental impairments. More prominent ventricular dilatation was associated with reduced rates of spontaneous resolution and increased rates of severe neurodevelopmental impairment among newborns with PHVD. Understanding clinically relevant time points in the evolution of PHVD and predictors of spontaneous resolution may help inform the discussion around the optimal timing for intervention and allow for more precise prognostication in this population.

Vitamin D-regulated Gene Expression Profiles: Species-specificity and Cell-specific Effects on Metabolism and Immunity.

Vitamin D has pleiotropic physiological actions including immune system regulation, in addition to its classical role in calcium homeostasis. Hormonal 1,25-dihydroxyvitamin D (1,25D) signals through the nuclear vitamin D receptor, and large-scale expression profiling has provided numerous insights into its diverse physiological roles. To obtain a comprehensive picture of vitamin D signaling, we analyzed raw data from 94 (80 human, 14 mouse) expression profiles of genes regulated by 1,25D or its analogs. This identified several thousand distinct genes directly or indirectly up- or downregulated in a highly cell-specific manner in human cells using a 1.5-fold cut-off. There was significant overlap of biological processes regulated in human and mouse but minimal intersection between genes regulated in each species. Disease ontology clustering confirmed roles for 1,25D in immune homeostasis in several human cell types, and analysis of canonical pathways revealed novel and cell-specific roles of vitamin D in innate immunity. This included cell-specific regulation of several components of Nucleotide-binding Oligomerization Domain-like (NOD-like) pattern recognition receptor signaling, and metabolic events controlling innate immune responses. Notably, 1,25D selectively enhanced catabolism of branched-chain amino acids (BCAAs) in monocytic cells. BCAA levels regulate the major metabolic kinase mammalian Target of Rapamycin (mTOR), and pretreatment with 1,25D suppressed BCAA-dependent activation of mTOR signaling. Furthermore, ablation of BCAT1 expression in monocytic cells blocked 1,25D-induced increases in autophagy marker LAMP1. In conclusion, the data generated represents a powerful tool to further understand the diverse physiological roles of vitamin D signaling and provides multiple insights into mechanisms of innate immune regulation by 1,25D.