Regulation of mast cells by overlapping but distinct protein interactions of Siglec-6 and Siglec-8.

BACKGROUND: Sialic acid-binding immunoglobulin-like lectin (Siglec)-6 and Siglec-8 are closely related mast cell (MC) receptors with broad inhibitory activity, but whose functional differences are incompletely understood. METHODS: Proteomic profiling using quantitative mass spectrometry was performed on primary mouse MCs to identify proteins associated with Siglec-6 and Siglec-8. For functional characterization, each receptor was evaluated biochemically and in ex vivo and in vivo inhibition models of IgE and non-IgE-mediated MC activation in Siglec-6- or Siglec-8-expressing transgenic mice. RESULTS: Siglec-6 and Siglec-8 were found in MCs within large complexes, interacting with 66 and 86 proteins, respectively. Strikingly, Siglec-6 and Siglec-8 interacted with a large cluster of proteins involved in IgE and non-IgE-mediated MC activation, including the high affinity IgE receptor, stem cell factor (SCF) receptor KIT/CD117, IL-4 and IL-33 receptors, and intracellular kinases LYN and JAK1. Protein interaction networks revealed Siglec-6 and Siglec-8 had overlapping yet distinct MC functions, with a potentially broader regulatory role for Siglec-6. Indeed, Siglec-6 preferentially interacted with the mature form of KIT at the cell surface, and treatment with an anti-Siglec-6 antibody significantly inhibited SCF-mediated MC activation more in comparison to targeting Siglec-8. CONCLUSION: These data demonstrate a central role for Siglec-6 and Siglec-8 in controlling MC activation through interactions with multiple activating receptors and key signaling molecules. Our findings suggest that Siglec-6 has a role distinct from that of Siglec-8 in regulating MC function and represents a distinct potential therapeutic target in mast cell-driven diseases.

Macro- and micro-scale culture environment differentially regulate the effects of crowding on macrophage function.

Macrophages hold vital roles in immune defense, wound healing, and tissue homeostasis, and have the exquisite ability to sense and respond to dynamically changing cues in their microenvironment. Much of our understanding of their behavior has been derived from studies performed using in vitro culture systems, in which the cell environment can be precisely controlled. Recent advances in miniaturized culture platforms also offer the ability to recapitulate some features of the in vivo environment and analyze cellular responses at the single-cell level. Since macrophages are sensitive to their surrounding environments, the specific conditions in both macro- and micro-scale cultures likely contribute to observed responses. In this study, we investigate how the presence of neighboring cells influence macrophage activation following proinflammatory stimulation in both bulk and micro-scale culture. We found that in bulk cultures, higher seeding density negatively regulated the average TNF-α secretion from individual macrophages in response to inflammatory agonists, and this effect was partially caused by the reduced cell-to-media volume ratio. In contrast, studies conducted using microwells to isolate single cells and groups of cells revealed that increasing numbers of cells positively influences their inflammatory activation, suggesting that the absolute cell numbers in the system may be important. In addition, a single inflammatory cell enhanced the inflammatory state of a small group of cells. Overall, this work helps to better understand how variations of macroscopic and microscopic culture environments influence studies in macrophage biology and provides insight into how the presence of neighboring cells and the soluble environment influences macrophage activation.

Multisystem inflammatory syndrome in 1.2 million children: longitudinal cohort study of risk factors.

BACKGROUND: We identified patient characteristics associated with an increased risk of developing MIS-C. METHODS: We conducted a longitudinal cohort study of 1,195,327 patients aged 0-19 years between 2006 and 2021, including the first two waves of the pandemic (February 25-August 22, 2020 and August 23, 2020-March 31, 2021). Exposures included prepandemic morbidity, birth outcomes, and family history of maternal disorders. Outcomes included MIS-C, Kawasaki disease, and other Covid-19 complications during the pandemic. We calculated risk ratios (RRs) and 95% confidence intervals (CIs) for the association between patient exposures and these outcomes using log-binomial regression models adjusted for potential confounders. RESULTS: Among 1,195,327 children, 84 developed MIS-C, 107 Kawasaki disease, and 330 other Covid-19 complications during the first year of the pandemic. Prepandemic hospitalizations for metabolic disorders (RR 11.3, 95% CI 5.61-22.6), atopic conditions (RR 3.34, 95% CI 1.60-6.97), and cancer (RR 8.11, 95% CI 1.13-58.3) were strongly associated with the risk of MIS-C, compared with no exposure. These same exposures were also associated with Kawasaki disease and other Covid-19 complications. However, birth characteristics and history of maternal morbidity were not associated with MIS-C development. CONCLUSIONS: Children with pre-existing morbidity have a considerably elevated risk of MIS-C. IMPACT: Morbidities that predispose children to multisystem inflammatory syndrome (MIS-C) are unclear. In this study, prepandemic hospitalizations for metabolic disorders, atopic conditions, and cancer were associated with an elevated risk of MIS-C. Birth characteristics and family history of maternal morbidity were not, however, associated with MIS-C. Pediatric morbidities may play a greater role in MIS-C onset than maternal or perinatal characteristics, and may help clinicians better recognize children at risk for this complication.

Congenital anomalies during Covid-19: artifact of surveillance or a real TORCH?

Infections in the first trimester of pregnancy can be teratogenic, but the possibility that Covid-19 could lead to birth defects is unclear. We examined whether SARS-CoV-2 infection during pregnancy or exposure to pandemic conditions were associated with the risk of congenital anomalies. We carried out a retrospective study of 420,222 neonates born in Quebec, Canada in two time periods: prepandemic (January 1, 2017 to March 12, 2020) vs. pandemic (March 13, 2020 to March 31, 2022). We classified pandemic births as early (first trimester completed before the pandemic) or late (first trimester during the pandemic), and identified patients with SARS-CoV-2 infections during pregnancy. We applied (1) adjusted log-binomial regression models to assess the association between SARS-CoV-2 infection and congenital anomalies, and (2) autoregressive interrupted time series regression to analyze temporal trends in the monthly number of defects in all patients regardless of infection. In total, 29,263 newborns (7.0%) had a congenital anomaly. First trimester SARS-CoV-2 infections were not associated with a greater risk of birth defects compared with no infection (RR 1.07, 95% CI 0.59-1.95). However, births during the late pandemic period were more likely to be diagnosed with congenital microcephaly compared with prepandemic births (RR 1.44, 95% CI 1.21-1.71). Interrupted time series analysis confirmed that the frequency of microcephaly increased during the late pandemic period, whereas other anomalies did not. We conclude that Covid-19 is likely not teratogenic, but enhanced surveillance of anomalies among late pandemic births may have heightened the detection of infants with microcephaly.

Impact of preterm birth on muscle mass and function: a systematic review and meta-analysis.

Individuals born preterm present lower exercise capacity. Along with the cardiopulmonary responses and activity level, muscle strength is a key determinant of exercise capacity. This systematic review aimed to summarize the current knowledge on the impact of preterm birth on skeletal muscle mass and function across the lifespan. The databases PubMed, MEDLINE, EBM, Embase, CINAHL Plus, Global Index Medicus, and Google Scholar were searched using keywords and MeSH terms related to skeletal muscle, preterm birth, and low birth weight. Two independent reviewers undertook study selection, data extraction, and quality appraisal using Covidence review management. Data were pooled to estimate the prematurity effect on muscle mass and function using the R software. From 4378 studies retrieved, 132 were full-text reviewed and 25 met the inclusion/exclusion criteria. Five studies presented a low risk of bias, and 5 had a higher risk of bias due to a lack of adjustment for confounding factors and presenting incomplete outcomes. Meta-analyses of pooled data from homogenous studies indicated a significant reduction in muscle thickness and jump test (muscle power) in individuals born preterm versus full-term with standardized mean difference and confidence interval of - 0.58 (0.27, 0.89) and - 0.45 (0.21, 0.69), respectively.    Conclusion: Overall, this systematic review summarizing the existing literature on the impact of preterm birth on skeletal muscle indicates emerging evidence that individuals born preterm, display alteration in the development of their skeletal muscle mass and function. This work also highlights a clear knowledge gap in understanding the effect of preterm birth on skeletal muscle development. What is Known: • Preterm birth, which occurs at a critical time of skeletal muscle development and maturation, impairs the development of different organs and tissues leading to a higher risk of comorbidities such as cardiovascular diseases. • Preterm birth is associated with reduced exercise capacity. What is New: • Individuals born preterm display alterations in muscle mass and function compared to individuals born at term from infancy to adulthood. • There is a need to develop preventive or curative interventions to improve skeletal muscle health in preterm-born individuals.

How to measure patient and family important outcomes in extremely preterm infants: A scoping review.

AIM: Parents of children born preterm have identified outcomes to be measured for audit and research at 18-24 months of age: child well-being, quality of life/function, socio-emotional/behavioural outcomes, respiratory, feeding, sleeping, and caregiver mental health. The aim was to identify the best tools to measure these seven domains. METHODS: Seven working groups completed literature reviews and evaluated potential tools to measure these outcomes in children aged 18-24 months. A group of experts and parents voted on the preferred tools in a workshop and by questionnaire. Consensus was 80% agreement. RESULTS: Consensus was obtained for seven brief, inexpensive, parent friendly valid measures available in English or French for use in a minimum dataset and potential alternative measures for use in funded research. CONCLUSION: Valid questionnaires and tools to measure parent-identified outcomes in young preterm children exist. This study will facilitate research and collection of data important to families.

Cardiopulmonary response to exercise in adults born very preterm.

This study aims to compare cardiopulmonary response to aerobic exercise between young adults born very preterm, including a subgroup with bronchopulmonary dysplasia (BPD), and term controls.Seventy-one adults (18-29 years) born <30 weeks' gestational age (24 with BPD) and 73 term controls were recruited. Assessment included cardiopulmonary exercise testing with impedance cardiography. We compared group differences in peak O2 consumption (peak VO2) and in ventilatory and cardiovascular responses to exercise using linear regression analyses.Preterm participants had reduced peak VO2 (mean difference -2.7; 95% CI -5.3, -0.1 mL·kg-1 lean body mass·min-1) versus controls. Those with BPD achieved lower peak work-rate compared to term controls (-21; 95% CI -38, -5 watts). There was no difference across groups in breathing reserve, ventilatory efficiency, peak heart rate and cardiac output. VO2 to work-rate relationship (ΔVO2/ΔWR) was reduced in preterm versus term. Peak systolic blood pressure and circulatory power (systolic blood pressure*VO2) were also lower in BPD versus term controls. In the preterm group, longer NICU stay and lower peak cardiac output were associated with lower peak VO2Results suggest limitations with peripheral O2 uptake in the muscle with reduced ΔVO2/ΔWR and peak circulatory power, but normal cardiac output. Investigations into skeletal muscle perfusion and O2 use during exercise are warranted to better understand mechanisms of exercise limitation.

Association of Postnatal Growth Changes and Neurodevelopmental Outcomes in Preterm Neonates of <29 Weeks' Gestation.

OBJECTIVE: To examine associations between weight and head circumference (HC) changes and neurodevelopment in preterm infants. STUDY DESIGN: This retrospective cohort study of Canadian Neonatal Network and Canadian Neonatal Follow-Up Network sites included preterm infants born 2010-2018. Logistic regression and model diagnostics evaluated relationships between changes in z score and velocity of weight and HC from birth to discharge from a tertiary neonatal intensive care unit, discharge to 18-24 months corrected age (CA), and birth to 18-24 months CA and significant cognitive/motor impairment at 18-24 months CA classified using a Bayley Scales of Infant and Toddler Development-Third Edition cognitive or motor composite score <70. RESULTS: In total, 4530 infants (53.0% male) with a mean (SD) gestational age of 26.3 (1.4) weeks and birth weight of 920 (227) g were included. Weight and HC changes were associated with lower odds of significant cognitive/motor impairment including an OR of 0.87 (95% CI: 0.83, 0.91; P < .001) for a 1-g/d increase in weight from discharge to 18-24 months CA and 0.81 (95% CI: 0.75, 0.88; P < .001) for a 1-unit increase in HC z score from birth to 18-24 months CA. Associations were not statistically significant in morbidity-free neonates. Weight and HC gains poorly discriminated between infants with and without significant cognitive/motor impairment (areas under the receiver operating characteristic curve of <0.64). No growth measure had a clinically useful balance of sensitivity and specificity. CONCLUSIONS: Weight and HC changes were associated with significant cognitive/motor impairment but had poor discriminatory capability. Neonatal morbidities may make a larger contribution than postnatal growth to neurodevelopment.

Guilt and Regret Experienced by Parents of Children Born Extremely Preterm.

OBJECTIVES: To explore decisional regret of parents of babies born extremely preterm and analyze neonatal, pediatric, and parental factors associated with regret. STUDY DESIGN: Parents of infants born <29 weeks of gestational age, aged between 18 months and 7 years, attending neonatal follow-up were enrolled. Hospital records were reviewed to examine morbidities and conversations with parents about levels of care. Parents were asked the following question: "Knowing what you know now, is there anything you would have done differently?" Mixed methods were used to analyze responses. RESULTS: In total, 248 parents (98% participation) answered, and 54% reported they did not have regret. Of those who reported regret (n = 113), 3 themes were most frequently invoked: 35% experienced guilt, thinking they were responsible for the preterm birth; 28% experienced regret about self-care decisions; and 20% regretted decisions related to their parental role, generally wishing they knew sooner how to get involved. None reported regret about life-and-death decisions made at birth or in the neonatal intensive care unit. Impairment at follow-up, gestational age, and decisions about levels/reorientation of care were not associated with regret. More mothers reported feeling guilt about the preterm birth (compared with fathers); parents of children with severe lesions on ultrasonography of the head were less likely to report regret. CONCLUSIONS: Approximately one-half of the parents of infants born extremely preterm had regrets regarding their neonatal intensive care unit stay. Causes of regret and guilt should be addressed and minimized.

Connection between maternal suicide attempt and chronic morbidity in children.

BACKGROUND: Maternal suicide attempts are associated with adverse psychosocial outcomes in children, but the association with chronic morbidity is poorly understood. We examined the relationship between maternal suicide attempt and risk of hospitalization for potentially preventable conditions in offspring. METHODS: We analyzed a longitudinal cohort of 1 032 210 children born in Quebec, Canada between 2006 and 2019. The main exposure measure was maternal suicide attempt before or during pregnancy. Outcomes included child hospitalizations for potentially preventable conditions, including infectious diseases, dental caries, atopy, and injury up to 14 years after birth. We used adjusted Cox proportional hazards regression models to estimate hazard ratios (HR) and 95% confidence intervals (CI) for the association of maternal suicide attempt with risk of hospitalization for these outcomes. RESULTS: Compared with no suicide attempt, children whose mothers attempted suicide had an increased risk of hospitalization for infectious diseases (HR 1.11, 95% CI 1.06-1.16), dental caries (HR 1.31, 95% CI 1.15-1.48), and injury (HR 1.16, 95% CI 1.03-1.31). Risk of hospitalization for any of these outcomes was greater if mothers attempted suicide by hanging (HR 1.46, 95% CI 1.22-1.75), had their first attempt between the age of 25 and 34 years (HR 1.27, 95% CI 1.13-1.42), and had 3 or more attempts (HR 1.56, 95% CI 1.27-1.91). Maternal suicide attempts were more strongly associated with child hospitalization before 10 years of age. CONCLUSIONS: Children whose mothers have a history of suicide attempt have an elevated risk of hospitalization for potentially preventable conditions.

Paediatric inflammatory multisystem syndrome in Canada: population-based surveillance and role of SARS-CoV-2 linkage.

BACKGROUND: Paediatric inflammatory multisystem syndrome (PIMS) is a rare condition temporally associated with SARS-CoV-2 infection. Using national surveillance data, we compare presenting features and outcomes among children hospitalized with PIMS by SARS-CoV-2 linkage, and identify risk factors for intensive care (ICU). METHODS: Cases were reported to the Canadian Paediatric Surveillance Program by a network of >2800 pediatricians between March 2020 and May 2021. Patients with positive versus negative SARS-CoV-2 linkages were compared, with positive linkage defined as any positive molecular or serologic test or close contact with confirmed COVID-19. ICU risk factors were identified with multivariable modified Poisson regression. RESULTS: We identified 406 children hospitalized with PIMS, including 49.8% with positive SARS-CoV-2 linkages, 26.1% with negative linkages, and 24.1% with unknown linkages. The median age was 5.4 years (IQR 2.5-9.8), 60% were male, and 83% had no comorbidities. Compared to cases with negative linkages, children with positive linkages experienced more cardiac involvement (58.8% vs. 37.4%; p < 0.001), gastrointestinal symptoms (88.6% vs. 63.2%; p < 0.001), and shock (60.9% vs. 16.0%; p < 0.001). Children aged ≥6 years and those with positive linkages were more likely to require ICU. CONCLUSIONS: Although rare, 30% of PIMS hospitalizations required ICU or respiratory/hemodynamic support, particularly those with positive SARS-CoV-2 linkages. IMPACT: We describe 406 children hospitalized with paediatric inflammatory multisystem syndrome (PIMS) using nationwide surveillance data, the largest study of PIMS in Canada to date. Our surveillance case definition of PIMS did not require a history of SARS-CoV-2 exposure, and we therefore describe associations of SARS-CoV-2 linkages on clinical features and outcomes of children with PIMS. Children with positive SARS-CoV-2 linkages were older, had more gastrointestinal and cardiac involvement, and hyperinflammatory laboratory picture. Although PIMS is rare, one-third required admission to intensive care, with the greatest risk amongst those aged ≥6 years and those with a SARS-CoV-2 linkage.

Shifting age of child eating disorder hospitalizations during the Covid-19 pandemic.

BACKGROUND: We studied the effect of the Covid-19 pandemic on child eating disorder hospitalizations in Quebec, Canada. Quebec had one of the strictest lockdown measures targeting young people in North America. METHODS: We analyzed eating disorder hospitalizations in children aged 10-19 years before and during the pandemic. We used interrupted time series regression to assess trends in the monthly number of hospitalizations for anorexia nervosa, bulimia nervosa, and other eating disorders before the pandemic (April 2006 to February 2020), and during the first (March to August 2020) and second waves (September 2020 to March 2021). We determined the types of eating disorders requiring hospital treatment and identified the age, sex and socioeconomic subgroups that were most affected. RESULTS: Hospitalization rates for eating disorders increased during the first (6.5 per 10,000) and second waves (12.8 per 10,000) compared with the period before the pandemic (5.8 per 10,000). The increase occurred for anorexia nervosa as well as other types of eating disorders. The number of girls and boys aged 10-14 years admitted for eating disorders increased during wave 1. Wave 2 triggered an increase in eating disorder admissions among girls aged 15-19 years. Hospitalization rates increased earlier for advantaged than disadvantaged youth. CONCLUSIONS: The Covid-19 pandemic affected hospitalizations for anorexia nervosa as well as other eating disorders, beginning with girls aged 10-14 years during wave 1, followed by girls aged 15-19 years during wave 2. Boys aged 10-14 years were also affected, as well as both advantaged and disadvantaged youth.

Sleep-disordered breathing symptoms and their association with structural and functional pulmonary changes in children born extremely preterm.

This study aimed to evaluate symptoms of sleep-disordered breathing (SDB) among children born extremely preterm, with and without a history of bronchopulmonary dysplasia (BPD), including associations between sleep and respiratory symptoms, physical activity, pulmonary function, and pulmonary magnetic resonance imaging (MRI). This multi-center cross-sectional study enrolled children aged 7-9 years born extremely preterm with and without BPD. Participants completed the Pediatric Sleep Questionnaire (PSQ), the modified Epworth sleepiness scale, a respiratory symptom questionnaire, pedometer measurements, pulmonary function testing, and pulmonary MRI. Spearman's correlations and univariate and multivariable linear regression modelling were performed. Twenty-eight of 45 children included had a history of moderate-to-severe BPD. The prevalence of sleep-related symptoms was low, with the exception of hyperactivity and inattention. There were no differences in mean (SD) scores on sleep questionnaires in children with and without BPD (PSQ: 0.21 (0.13) vs 0.16 (0.14), p = 0.3; modified Epworth: 2.4 (2.4) vs 1.8 (2.8), p = 0.4). Multiple regression analyses examining difference in sleep scores between groups, adjusting for gestational age and intraventricular hemorrhage, found no statistical difference (p > 0.05). Greater daytime sleepiness was moderately correlated with FEV1%-predicted (r = - 0.52); no other moderate-strong associations were identified.  Conclusions: There was no evidence of clinically important differences in sleep symptoms between children with and without BPD, suggesting that sleep symptoms may be related to prematurity-related factors other than a BPD diagnosis, including airflow limitation. Further research is necessary to explore the relationship between sleep symptoms, airway obstruction, and neurobehavioral symptoms among premature-born children.  Trial registration: NCT02921308. Date of registration: October 3, 2016. What is Known: • Presence of bronchopulmonary dysplasia (BPD) may further contribute to the development of SDB, though its impact is not well-studied. • Premature-born children have a greater risk of lung structural and functional differences, including sleep-disordered breathing (SDB). What is New: • There was no difference in sleep symptoms between children with and without BPD, suggesting that sleep symptoms are related to other prematurity-related factors, such as airflow limitation. • Greater daytime sleepiness was correlated with lower FEV1 in our population, which reflects greater airflow limitation.

Pulmonary important outcomes after extremely preterm birth: Parental perspectives.

AIM: To describe pulmonary important outcomes (PIO) reported by parents of children born extremely preterm. METHODS: Over 1-year, all parents of children aged 18 months-7-years born <29 weeks' GA were asked regarding their perspectives. The proportion of parents who described PIO and the themes they invoked were examined. Results were analysed using mixed methods. RESULTS: Among parental responses (n = 285, 98% participation rate), 44% spoke about PIO, invoking 24 themes pertaining to NICU hospitalisation and/or long-term respiratory health. Some themes had an impact primarily on the child (e.g. exercise limitation), while the majority had an impact on the whole family (e.g. hospital readmissions). None mentioned oxygen at 36 weeks nor bronchopulmonary dysplasia (BPD). The proportion of responses invoking PIO were statistically similar between parents of children with and without BPD, born before or after 25 weeks or with birthweight < or ≥750 g. PIO were more likely to be mentioned in males and among those readmitted for respiratory problems. CONCLUSION: Parents describe many PIO, most related to the functional impact of lung disease on their child (and family), rather than the diagnosis of BPD itself. Most of these PIO are not primary outcomes in large neonatal trials nor collected in neonatal databases.

Gratitude, fragility and strength: Perspectives of adults born preterm about prematurity.

AIM: The aim of the study was to explore how young adults thought that being born preterm had affected their lives. METHODS: Adult participants of a research cohort were questioned about their perspectives. Answers were analysed using mixed methods. RESULTS: Forty-five participants evaluated their health at median score of 8/10. When asked about the meaning of being born preterm, 65% had positive self-centred answers, invoking two main themes: being stronger/'a fighter'/more resilient and being a survivor/chosen; 42% also reported negative themes, such as having health problems and a difficult start. All heard about their prematurity from their parents, 55% with positive child-centred or healthcare system-centred themes, 19% with neutral themes; 35% also heard negative parent-centred themes (tragic experience, guilt, mother's health). When asked which words were associated with prematurity, participants mainly chose positive words for themselves and their family, but more negative words for how the media and society depicted prematurity. Answers were not correlated with adverse objective health measures. CONCLUSION: Participants evaluated their health in a balanced fashion. Preterm-born adults often feel that they have experienced positive transformations as a result of their traumatic start. They often have feelings of gratitude and strength, independent of health problems.

Parental perspectives of outcomes following very preterm birth: Seeing the good, not just the bad.

AIM: To describe parental perspective on health and developmental outcomes of their preterm child in relation to level of neurodevelopmental impairment (NDI). METHODS: A parental survey about their children aged 15-36 months corrected age born ˂29 weeks' gestation investigated parental concerns and positive attributes. Parental responses in relation to their child's level of NDI were examined using Kruskal-Wallis and chi-square for trend tests. RESULTS: One hundred ninety-nine parental responses were obtained for 163 children, including 44% with NDI. Vast majority of parents reported their children were developing well with good physical health. All parents, irrespective of NDI, reported their children were happy and had a positive personality. Appreciation of social interactions was higher for parents of children without versus with NDI (96% vs. 87%, p = 0.039). Parents of children with NDI were more likely to express concerns than those without NDI. Overall, development was the most common area of concern (45%), followed by the child's future (40%) and physical health (35%). CONCLUSION: Parents of preterm children report many positive points and concerns, some of which are not examined in neonatal follow-up data. These parental perspectives could be used to inform parents of preterm infants, both antenatally and in the neonatal unit.

Behavioral-play familiarization for non-sedated magnetic resonance imaging in young children with mild traumatic brain injury.

BACKGROUND: Mild traumatic brain injury (mTBI) sustained in early childhood affects the brain at a peak developmental period and may disrupt sensitive stages of skill acquisition, thereby compromising child functioning. However, due to the challenges of collecting non-sedated neuroimaging data in young children, the consequences of mTBI on young children's brains have not been systematically studied. In typically developing preschool children (of age 3-5years), a brief behavioral-play familiarization provides an effective alternative to sedation for acquiring awake magnetic resonance imaging (MRI) in a time- and resource-efficient manner. To date, no study has applied such an approach for acquiring non-sedated MRI in preschool children with mTBI who may present with additional MRI acquisition challenges such as agitation or anxiety. OBJECTIVE: The present study aimed to compare the effectiveness of a brief behavioral-play familiarization for acquiring non-sedated MRI for research purposes between young children with and without mTBI, and to identify factors associated with successful MRI acquisition. MATERIALS AND METHODS: Preschool children with mTBI (n=13) and typically developing children (n=24) underwent a 15-minutes behavioral-play MRI familiarization followed by a 35-minutes non-sedated MRI protocol. Success rate was compared between groups, MRI quality was assessed quantitatively, and factors predicting success were documented. RESULTS: Among the 37 participants, 15 typically developing children (63%) and 10 mTBI (77%) reached the MRI acquisition success criteria (i.e., completing the two first sequences). The success rate was not significantly different between groups (p=.48; 95% CI [-0.36 14.08]; Cramer's V=.15). The images acquired were of high-quality in 100% (for both groups) of the structural images, and 60% (for both groups) of the diffusion images. Factors associated with success included older child age (Β=0.73, p=.007, exp(B)=3.11, 95% CI [1.36 7.08]) and fewer parental concerns (Β=-1.56, p=.02, exp(Β)=0.21, 95% CI [0.05 0.82]) about the MRI procedure. CONCLUSION: Using brief behavioral-play familiarization allows acquisition of high-quality non-sedated MRI in young children with mTBI with success rates comparable to those of non-injured peers.

Severe neonatal birth injury: Observational study of associations with operative, cesarean, and spontaneous vaginal delivery.

AIM: To determine the association of successful and unsuccessful operative vaginal delivery attempts with risk of severe neonatal birth injury. METHODS: We conducted a population-based observational study of 1 080 503 births between 2006 and 2019 in Quebec, Canada. The main exposure was operative vaginal delivery with forceps or vacuum, elective or emergency cesarean with or without an operative vaginal attempt, and spontaneous delivery. The outcome was severe birth injury, including intracranial hemorrhage, brain and spinal damage, Erb's paralysis and other brachial plexus injuries, epicranial subaponeurotic hemorrhage, skull and long bone fractures, and liver, spleen, and other neonatal body injuries. We determined the association of delivery mode with risk of severe birth injury using adjusted risk ratios (RR) and 95% confidence intervals (CI). RESULTS: A total of 8194 infants (0.8%) had severe birth injuries. Compared with spontaneous delivery, vacuum (RR 2.98, 95% CI 2.80-3.16) and forceps (RR 3.35, 95% CI 3.07-3.66) were both associated with risk of severe injury. Forceps was associated with intracranial hemorrhage (RR 16.4, 95% CI 10.1-26.6) and brain and spinal damage (RR 13.5, 95% CI 5.72-32.0), while vacuum was associated with epicranial subaponeurotic hemorrhage (RR 27.5, 95% CI 20.8-36.4) and skull fractures (RR 2.04, 95% CI 1.86-2.25). Emergency cesarean after an unsuccessful operative attempt was associated with intracranial and epicranial subaponeurotic hemorrhage, but elective and other emergency cesareans were not associated with severe injury. CONCLUSIONS: Operative vaginal delivery and unsuccessful operative attempts that result in an emergency cesarean are associated with elevated risks of severe birth injury.

Matched cohort study of hospitalization in children who have siblings with cancer.

BACKGROUND: Health outcomes of children in families affected by cancer are poorly understood. The authors assessed the risk of hospitalization in children who have a sibling with cancer. METHODS: This was a longitudinal cohort study in which 1600 children who had a sibling with cancer were matched to 32,000 children who had unaffected siblings in Quebec, Canada, from 2006 to 2020. The exposure of interest was having a sibling with cancer. Outcomes included hospitalization for pneumonia, asthma, fracture, and other morbidities any time after the sibling was diagnosed with cancer. The children were followed over time, and Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the impact of having a sibling with cancer on the risk of hospitalization before age 14 years, adjusted for patient characteristics. RESULTS: Children who had a sibling with cancer had an increased risk of hospitalization compared with unaffected children (HR, 1.15; 95% CI, 1.02-1.29). Conditions associated with a greater risk of hospitalization included pneumonia, hemangioma, other skin conditions, sleep apnea, and inflammatory bowel disease. The risk of hospitalization was greatest for children whose older sibling had cancer (HR, 1.16; 95% CI, 1.01-1.32) and for children whose sibling had hematopoietic cancer (HR, 1.22; 95% CI, 1.01-1.48). CONCLUSIONS: Children who have a sibling with cancer are at risk of hospitalization for conditions such as pneumonia, inflammatory bowel disease, and other morbidities. Families affected by childhood cancer may benefit from additional support to facilitate care for all children in the family. LAY SUMMARY: Little is known about the health of children who have a brother or sister with cancer. The authors studied the types of hospitalization experienced by children who have siblings with cancer. The results indicated that having a sibling with cancer increased the chance of being hospitalized for pneumonia and other conditions that could have been preventable. The results also indicated that children who had an older sibling with cancer or a sibling with blood cancer had a greater chance of being hospitalized. The findings highlight the importance of providing timely care for children in families affected by childhood cancer.

Longitudinal risk of maternal hospitalization for mental illness following preterm birth.

BACKGROUND: Preterm birth may affect maternal mental health, yet most studies focus on postpartum mental disorders only. We explored the relationship between preterm delivery and the long-term risk of maternal hospitalization for mental illness after pregnancy. METHODS: We performed a longitudinal cohort study of 1,381,300 women who delivered between 1989 and 2021 in Quebec, Canada, and had no prior history of mental illness. The exposure was preterm birth, including extreme (<28 weeks), very (28-31 weeks), and moderate to late (32-36 weeks). The outcome was subsequent maternal hospitalization for depression, bipolar, psychotic, stress and anxiety, personality disorders, and self-harm up to 32 years later. We used adjusted Cox proportional hazards models to estimate hazard ratios (HR) and 95% confidence intervals (CI) for the association between preterm birth and mental illness hospitalization. RESULTS: Compared with term, women who delivered preterm had a higher rate of mental illness hospitalization (3.81 vs. 3.01 per 1000 person-years). Preterm birth was associated with any mental illness (HR 1.38, 95% CI 1.35-1.41), including depression (HR 1.37, 95% CI 1.32-1.41), psychotic disorders (HR 1.35, 95% CI 1.25-1.44), and stress and anxiety disorders (HR 1.42, 95% CI 1.38-1.46). Delivery at any preterm gestational age was associated with the risk of mental hospitalization, but risks were greatest around 34 weeks of gestation. Preterm birth was strongly associated with mental illness hospitalization within 2 years of pregnancy, although associations persisted throughout follow-up. CONCLUSIONS: Women who deliver preterm may be at risk of mental disorders in the short and long term.