Canadian Institutes For Health Research Research Articles

Regulation of the mitochondrial integrated stress response and ATF4 by acute contractile activity in mouse muscle

In the context of energetically demanding conditions, such as exercise, skeletal muscle relies on mitochondria to support its metabolic requirements. Maintenance of mitochondria and their bioenergetic availability is thus critical to sustain the metabolic flexibility of muscle. The quality of the organelle network is highly regulated by the coordination of mitochondrial quality control (MQC) processes. One MQC pathway that has garnered recent interest is the integrated stress response (ISR), which is activated in response to a variety of stimuli. The transcription factor ATF4, denoted as the main effector of this response pathway, serves to ameliorate cellular stress by upregulating a plethora of cytoprotective genes, such as CHOP and ATF5. Current literature has shown that the ISR is activated upon mitochondrial stress/perturbations to restore optimal organelle function and health. However, the precise mechanism that constitutes the activation of ISR and thus the response of ATF4 following acute exercise-induced stress is unknown. Therefore, our objective is to determine the extent of ISR/ATF4 induction in vivo and to test whether this pathway is required for the maintenance of muscle function. To investigate this, a mouse in situ hindlimb protocol was utilized to acutely stimulate muscles at 0.25-1 tetani/per second for 9 mins, followed by a 1-hour recovery period. The kinases, CAMKIIα and JNK2, were robustly phosphorylated/activated 6-fold immediately following the protocol. The initial stage of ISR activation, reflected in the ratio of phosphorylated to total-eIF2α protein levels, was also increased in response to acute contractile activity, evident in the recovery phase. Downstream of ISR activation, the total protein expression of ATF4 remained unchanged, however, contractile activity induced an increase in the localization of ATF4 to the nucleus. Robust 2-fold increases in the mRNA expression of ATF4 and CHOP were also observed and enhanced following the recovery period. Changes in ATF4 mRNA appeared to be independent of transcriptional activation, as assessed using an ATF4 promoter-reporter plasmid. An in vitro cell free mRNA decay assay revealed an increase in ATF4 mRNA stability post-stimulation, possibly as a result of cellular compartmental changes in the RNA binding proteins, HuR and CUGBP1. RNA sequencing analyses also confirmed the observed increase in related ISR genes following an exhaustive bout of exercise. These data suggest that acute contractile activity is indeed suffcient to induce mitochondrial stress and activate the ISR, corresponding to the induction of ATF4. Future work will reveal the underlying mitochondrial signal responsible for activating this pathway, as well as the downstream consequences for the regulation of MQC processes in maintaining mitochondrial homeostasis. This work was supported by funds from the Canadian Institutes for Health Research (CIHR). Victoria C. Sanfrancesco is the recipient of the CIHR Frederick Banting and Charles Best Canada Graduate Scholarship-Master's (CGS-M). David A. Hood is the holder of a Canadian Research Chair in Cell Physiology. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Effect of Heat Exposure on Inflammation and Platelet Activity in Adults with Heart Disease

INTRODUCTION: Extreme heat events are associated with a greater risk of cardiovascular mortality, especially in adults with pre-existing heart disease. The pathophysiological mechanisms mediating these relationships remain unknown. One proposed mechanism, supported by pre-clinical studies employing heat stroke models of severe body hyperthermia, is that heat exposure causes an inflammatory response leading to platelet activation and clot formation. It remains unknown if milder body hyperthermia, such as the one experienced during exposure to a hot environment, elicits an inflammatory response and/or increases platelet activity in adults living with heart disease.OBJECTIVES & HYPTOHESES: To assess whether exposure to a hot and humid environment (1) increases circulating concentrations of inflammatory cytokines and (2) induces platelet activation in adults with heart disease.METHODOLOGY: Adults living with coronary artery disease (67±8 years; 13M/2F) sat within a climate chamber maintained at 38°C and 50% humidity for 3h. Core (rectal) and skin temperatures were measured continuously. Blood samples were drawn before and 2.5h into heat exposure. The blood samples were analyzed for IL-6, IL-8, IL-18, TNFα and IL-1β (multiplexed bead-based immunoassay). Platelet aggregation was measured by impedance (Multiplate assay) induced with ADP (6.5 μM), TRAP (15 μM) and collagen (1.5 μg/ml). The total-thrombus analysis system (T-TAS, PL-CHIP) was used to measure thrombus onset time and total thrombogenicity.RESULTS: Core and skin temperatures increased by 0.35 ± 0.24°C and 4.85 ± 0.84°C, respectively (p<0.05). There were no changes (Δpost-pre) in IL-6 (0.31 ± 1.91 pg/ml, p=0.60), IL-18 (-10.29 ± 21.01 pg/ml, p=0.16), IL-8 (1.10 ± 2.39 pg/ml, p=0.18), TNFα (-1.12 ± 4.10 pg/ml, p =0.39), or IL-1β (0.53 ± 2.36 pg/ml, p=0.48) during heat exposure. Moreover, heat exposure did not increase platelet activation in response to ADP (-8.31 ± 33.70 U, p=0.34), TRAP (16.19 ± 36.54 U, p=0.10), or collagen (-9.19 ± 30.31 U, p=0.24). Lastly, there was no change in thrombus onset time (2.18 ± 37.31 s, p=0.850) or total thrombogenicity (2.8 ± 168.7 PL-AUC, p=0.90).CONCLUSION: These results suggest that inflammation predisposing to thrombus formation may not contribute to the greater cardiac risk associated with short-term exposure to humid heat. Canadian Institutes for Health Research. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Clinical and biological landscape of constitutional mismatch-repair deficiency syndrome: an International Replication Repair Deficiency Consortium cohort study

Constitutional mismatch repair deficiency (CMMRD) syndrome is a rare and aggressive cancer predisposition syndrome. Because a scarcity of data on this condition contributes to management challenges and poor outcomes, we aimed to describe the clinical spectrum, cancer biology, and impact of genetics on patient survival in CMMRD. In this cohort study, we collected cross-sectional and longitudinal data on all patients with CMMRD, with no age limits, registered with the International Replication Repair Deficiency Consortium (IRRDC) across more than 50 countries. Clinical data were extracted from the IRRDC database, medical records, and physician-completed case record forms. The primary objective was to describe the clinical features, cancer spectrum, and biology of the condition. Secondary objectives included estimations of cancer incidence and of the impact of the specific mismatch-repair gene and genotype on cancer onset and survival, including after cancer surveillance and immunotherapy interventions. We analysed data from 201 patients (103 males, 98 females) enrolled between June 5, 2007 and Sept 9, 2022. Median age at diagnosis of CMMRD or a related cancer was 8·9 years (IQR 5·9-12·6), and median follow-up from diagnosis was 7·2 years (3·6-14·8). Endogamy among minorities and closed communities contributed to high homozygosity within countries with low consanguinity. Frequent dermatological manifestations (117 [93%] of 126 patients with complete data) led to a clinical overlap with neurofibromatosis type 1 (35 [28%] of 126). 339 cancers were reported in 194 (97%) of 201 patients. The cumulative cancer incidence by age 18 years was 90% (95% CI 80-99). Median time between cancer diagnoses for patients with more than one cancer was 1·9 years (IQR 0·8-3·9). Neoplasms developed in 15 organs and included early-onset adult cancers. CNS tumours were the most frequent (173 [51%] cancers), followed by gastrointestinal (75 [22%]), haematological (61 [18%]), and other cancer types (30 [9%]). Patients with CNS tumours had the poorest overall survival rates (39% [95% CI 30-52] at 10 years from diagnosis; log-rank p<0·0001 across four cancer types), followed by those with haematological cancers (67% [55-82]), gastrointestinal cancers (89% [81-97]), and other solid tumours (96% [88-100]). All cancers showed high mutation and microsatellite indel burdens, and pathognomonic mutational signatures. MLH1 or MSH2 variants caused earlier cancer onset than PMS2 or MSH6 variants, and inferior survival (overall survival at age 15 years 63% [95% CI 55-73] for PMS2, 49% [35-68] for MSH6, 19% [6-66] for MLH1, and 0% for MSH2; p<0·0001). Frameshift or truncating variants within the same gene caused earlier cancers and inferior outcomes compared with missense variants (p<0·0001). The greater deleterious effects of MLH1 and MSH2 variants as compared with PMS2 and MSH6 variants persisted despite overall improvements in survival after surveillance or immune checkpoint inhibitor interventions. The very high cancer burden and unique genomic landscape of CMMRD highlight the benefit of comprehensive assays in timely diagnosis and precision approaches toward surveillance and immunotherapy. These data will guide the clinical management of children and patients who survive into adulthood with CMMRD. The Canadian Institutes for Health Research, Stand Up to Cancer, Children's Oncology Group National Cancer Institute Community Oncology Research Program, Canadian Cancer Society, Brain Canada, The V Foundation for Cancer Research, BioCanRx, Harry and Agnieszka Hall, Meagan's Walk, BRAINchild Canada, The LivWise Foundation, St Baldrick Foundation, Hold'em for Life, and Garron Family Cancer Center.

Development of an anxiety disorder following an emergency department visit due to cannabis use: a population-based cohort study

There is ongoing uncertainty about whether cannabis use increases the risk of developing an anxiety disorder. In this study we estimated the risk of having an incident healthcare visit for an anxiety disorder following an emergency department (ED) visit for cannabis use and explored factors associated with increased risk. We used health administrative data to perform a population-based cohort study of all individuals aged 10-105 years with no previous healthcare visits for anxiety disorders in Ontario, Canada, between January 2008 and March 2019. We compared the risk of having an incident healthcare visit for an anxiety disorder in the ED or hospital (primary analysis) or additionally in an outpatient setting (secondary analysis) for individuals with an incident ED visit for cannabis to members of the general population using cumulative incidence functions and cause-specific hazard models adjusted for relevant confounders. Our study included 12,099,144 individuals aged 10-105 without prior care for an anxiety disorder in the ED or hospital, of which 34,822 (0.29%) had an incident ED visit due to cannabis. Within 3-years of an incident ED visit due to cannabis, 12.3% (n=4294) of individuals had an incident ED visit or hospitalization for an anxiety disorder-a 3.7-fold (adjusted Hazard Ratio [aHR] 3.69 95% CI 3.57-3.82) increased risk relative to the general population (1.2%). In secondary analysis, further excluding individuals with prior outpatient care for anxiety disorders, 23.6% of individuals with an ED visit due to cannabis had an incident outpatient visit, ED visit, or hospitalization for an anxiety disorder within 3-years compared to 5.6% of individuals in the general population (aHR 3.88 95% CI 3.77-2.99). The risk of having an incident healthcare visit for an anxiety disorder was higher in individuals with ED visits for cannabis use compared to the general population across all age and sex strata. However, younger males with ED visits for cannabis use (aHR 5.67 95% CI 5.19-6.21) had a greater risk relative to the general population than younger women with cannabis use (aHR 3.22 95% CI 2.95-3.52). ED visits for cannabis use were associated with an increased risk of having an incident healthcare visit for an anxiety disorder, particularly in young males. These findings have important clinical and policy implications given the increasing use of cannabis over time and trend towards legalization of cannabis. Canadian Institutes for Health Research.

Stigmatization of Ebola virus disease survivors in 2022: A cross-sectional study of survivors in Sierra Leone

BackgroundEvidence has demonstrated a high proportion of Ebola virus disease (EVD) survivors experienced stigma due to the disease. This study sought to understand the longer-term effects of stigma encountered by survivors of the 2014–2016 EVD epidemic living in Sierra Leone. MethodsThis was a cross-sectional study of 595 EVD survivors and 403 close contacts (n = 998) from Sierra Leone. Assessments were conducted using a three-part survey between November 2021 to March 2022. We explored the socio-demographic factors associated with stigma experienced by EVD survivors. Findings50·6 % (n = 301) of EVD survivors reported that they continued to experience at least one aspect of stigma. Females were disproportionately affected by stigma, with 45·2 % of females reporting isolation from friends and family compared to 33·9 % of men (p = 0·005). Multivariable logistic regression models revealed those aged 40–44, living rurally, and reporting an acute infection longer than seven days was associated with EVD-related stigma at the time of survey. InterpretationThis study demonstrates stigma is still prevalent among people who survived EVD in 2022. It also identified socio-demographic factors associated with stigma that can be used for targeting interventions. Importantly, this highlights the continued need for EVD survivors to access mental healthcare and social support systems well after disease recovery. FundingThis study was funded by the Canadian Institutes for Health Research (Grant no. PJT-175098. JK is funded by a Tier 2 Canada Research Chair in the Molecular Pathogenesis of Emerging and Re-Emerging Viruses. SS is funded by a Tier 2 Canada Research Chair in Program Science and Global Public Health.

Analysis of intestinal epithelial cell responses to IFN-γ during Cryptosporidiuminfection

Abstract Cryptosporidium species are intracellular parasites that infect intestinal epithelial cells (IEC) and the rapid cycle of growth, cell lysis and reinfection every 12 hours can cause severe enteric disease in young or immunocompromised patients. Interferon-γ (IFN-γ) has a crucial role in protective immunity and mice with an IEC-specific deletion of the IFN-γ receptor (IFN-γR ΔIEC) are highly susceptible to infection. However, the dynamics of IFN-γ signalling to IEC and how this leads to parasite control remain poorly understood. Based on the use of a reporter mouse for IFN signalling in vivo, while macrophages showed a transient response to treatment with IFN-γ, IEC exhibited a sustained response to IFN-γ that peaks at 24h. Indeed, the treatment of mice with recombinant IFN-γ transiently limits parasite shedding but takes 24h to show protective activity. Single-cell RNA sequencing of enterocytes from naïve and infected mice identified upregulation of several IFN-γ-inducible effectors but highlighted that induction of these genes was comparable in infected and bystander IEC. Together, these results suggest that while Cryptosporidium-infected cells are responsive to IFN-γ signalling, the protective effects of IFN-γ may be mediated through activation of uninfected bystander enterocytes. These studies provide new insights into the dynamics and function of IFN-γ signalling on IEC that are broadly relevant to other IEC-restricted pathogens. Supported by grants from NIH (R01 AI148249) and post-doctoral fellowships from the Canadian Institutes for Health Research and Fonds de Recherche du Québec – Santé.

Severity and duration of dysglycemia and brain injury among patients with neonatal encephalopathy

Evidence is needed to inform thresholds for glycemic management in neonatal encephalopathy (NE). We investigated how severity and duration of dysglycemia relate to brain injury after NE. A prospective cohort of 108 neonates ≥36 weeks gestational age with NE were enrolled between August 2014 and November 2019at the Hospital for Sick Children, in Toronto, Canada. Participants underwent continuous glucose monitoring for 72h, MRI at day 4 of life, and follow-up at 18 months. Receiver operating characteristic curves were used to assess the predictive value of glucose measures (minimum and maximum glucose, sequential 1mmol/L glucose thresholds) during the first 72h of life (HOL) for each brain injury pattern (basal ganglia, watershed, focal infarct, posterior-predominant). Linear and logistic regression analyses were used to assess the relationship between abnormal glycemia and 18-month outcomes (Bayley-III composite scores, Child Behavior Checklist [CBCL] T-scores, neuromotor score, cerebral palsy [CP], death), adjusting for brain injury severity. Of 108 neonates enrolled, 102 (94%) had an MRI. Maximum glucose during the first 48 HOL best predicted basal ganglia (AUC=0.811) and watershed (AUC=0.858) injury. Minimum glucose was not predictive of brain injury (AUC <0.509). Ninety-one (89%) infants underwent follow-up assessments at 19.0±1.7 months. A glucose threshold of >10.1mmol/L during the first 48 HOL was associated with 5.8-point higher CBCL Internalizing Composite T-score (P=0.029), 0.3-point worse neuromotor score (P=0.035), 8.6-fold higher odds for CP diagnosis (P=0.014). While the glucose threshold of >10.1mmol/L during the first 48 HOL was associated with higher odds of the composite outcome of severe disability or death (OR 3.0, 95% CI 1.0-8.4, P=0.042), it was not associated with the composite outcome of moderate-to-severe disability or death (OR 0.9, 95% CI 0.4-2.2, P=0.801). All associations with outcome lost significance after adjusting for brain injury severity. Maximum glucose concentration in the first 48 HOL is predictive of brain injury after NE. Further trials are needed to assess if protocols to control maximum glucose concentrations improve outcomes after NE. Canadian Institutes for Health Research, National Institutes of Health, and SickKids Foundation.

Planting Seeds of Change: Voices of Indigenous Youth on Wholistic Health

Indigenous youth are key partners in improving our understanding of holistic health and identifying solutions to address health-related issues. The Urban Gardens Project was a community-based research partnership involving Indigenous youth co-researchers, Brandon University, Indigenous Knowledge Users, Elders, and Indigenous organizations in Winnipeg and Brandon, Manitoba. Using the Medicine Wheel as an analytic framework, the study identified key indicators of spiritual, mental, physical, and emotional wellbeing that Indigenous youth attributed to gardening. Findings illuminate the need for policies to foster Indigenous youth engagement, leadership, and urban gardening programs that advance Indigenous cultural practices to contribute to Indigenous health and wellbeing. The research was funded by the Canadian Institutes for Health Research (CIHR).

Colchicine and the combination of rivaroxaban and aspirin in patients hospitalised with COVID-19 (ACT): an open-label, factorial, randomised, controlled trial

COVID-19 disease is accompanied by a dysregulated immune response and hypercoagulability. The Anti-Coronavirus Therapies (ACT) inpatient trial aimed to evaluate anti-inflammatory therapy with colchicine and antithrombotic therapy with the combination of rivaroxaban and aspirin for prevention of disease progression in patients hospitalised with COVID-19. The ACT inpatient, open-label, 2 × 2 factorial, randomised, controlled trial was done at 62 clinical centres in 11 countries. Patients aged at least 18 years with symptomatic, laboratory confirmed COVID-19 who were within 72 h of hospitalisation or worsening clinically if already hospitalised were randomly assigned (1:1) to receive colchicine 1·2 mg followed by 0·6 mg 2 h later and then 0·6 mg twice daily for 28 days versus usual care; and in a second (1:1) randomisation, to the combination of rivaroxaban 2·5 mg twice daily plus aspirin 100 mg once daily for 28 days versus usual care. Investigators and patients were not masked to treatment allocation. The primary outcome, assessed at 45 days in the intention-to-treat population, for the colchicine randomisation was the composite of the need for high-flow oxygen, mechanical ventilation, or death; and for the rivaroxaban plus aspirin randomisation was the composite of major thrombosis (myocardial infarction, stroke, acute limb ischaemia, or pulmonary embolism), the need for high-flow oxygen, mechanical ventilation, or death. The trial is registered at www. gov, NCT04324463 and is ongoing. Between Oct 2, 2020, and Feb 10, 2022, at 62 sites in 11 countries, 2749 patients were randomly assigned to colchicine or control and the combination of rivaroxaban and aspirin or to the control. 2611 patients were included in the analysis of colchicine (n=1304) versus control (n=1307); 2119 patients were included in the analysis of rivaroxaban and aspirin (n=1063) versus control (n=1056). Follow-up was more than 98% complete. Overall, 368 (28·2%) of 1304 patients allocated to colchicine and 356 (27·2%) of 1307 allocated to control had a primary outcome (hazard ratio [HR] 1·04, 95% CI 0·90-1·21, p=0·58); and 281 (26·4%) of 1063 patients allocated to the combination of rivaroxaban and aspirin and 300 (28·4%) of 1056 allocated to control had a primary outcome (HR 0·92, 95% CI 0·78-1·09, p=0·32). Results were consistent in subgroups defined by vaccination status, disease severity at baseline, and timing of randomisation in relation to onset of symptoms. There was no increase in the number of patients who had at least one serious adverse event for colchicine versus control groups (87 [6·7%] of 1304 vs 90 [6·9%] of 1307) or with rivaroxaban and aspirin versus control groups (85 [8·0%] vs 91 [8·6%]). Among patients assigned to colchicine, 8 (0·61%) had adverse events that led to discontinuation of study drug, mostly gastrointestinal in nature. 17 (1·6%) patients assigned to the combination of rivaroxaban and aspirin had bleeding compared with seven (0·66%) of those allocated to control (p=0·042); the number of serious bleeding events was two (0·19%) versus six (0·57%), respectively (p=0·18). No patients assigned to rivaroxaban and aspirin had serious adverse events that led to discontinuation of study drug. Among patients hospitalised with COVID-19, neither colchicine nor the combination of rivaroxaban and aspirin prevent disease progression or death. Canadian Institutes for Health Research, Bayer, Population Health Research Institute, Hamilton Health Sciences Research Institute, Thistledown Foundation. For the Portuguese, Russian and Spanish translations of the abstract see Supplementary Materials section.

Colchicine and aspirin in community patients with COVID-19 (ACT): an open-label, factorial, randomised, controlled trial

The large number of patients worldwide infected with the SARS-CoV-2 virus has overwhelmed health-care systems globally. The Anti-Coronavirus Therapies (ACT) outpatient trial aimed to evaluate anti-inflammatory therapy with colchicine and antithrombotic therapy with aspirin for prevention of disease progression in community patients with COVID-19. The ACT outpatient, open-label, 2 × 2 factorial, randomised, controlled trial, was done at 48 clinical sites in 11 countries. Patients in the community aged 30 years and older with symptomatic, laboratory confirmed COVID-19 who were within 7 days of diagnosis and at high risk of disease progression were randomly assigned (1:1) to receive colchicine 0·6 mg twice daily for 3 days and then 0·6 mg once daily for 25 days versus usual care, and in a second (1:1) randomisation to receive aspirin 100 mg once daily for 28 days versus usual care. Investigators and patients were not masked to treatment allocation. The primary outcome was assessed at 45 days in the intention-to-treat population; for the colchicine randomisation it was hospitalisation or death, and for the aspirin randomisation it was major thrombosis, hospitalisation, or death. The ACT outpatient trial is registered at ClinicalTrials.gov, NCT04324463 and is ongoing. Between Aug 27, 2020, and Feb 10, 2022, 3917 patients were randomly assigned to colchicine or control and to aspirin or control; after excluding 36 patients due to administrative reasons 3881 individuals were included in the analysis (n=1939 colchicine vs n=1942 control; n=1945 aspirin vs 1936 control). Follow-up was more than 99% complete. Overall event rates were 5 (0·1%) of 3881 for major thrombosis, 123 (3·2%) of 3881 for hospitalisation, and 23 (0·6%) of 3881 for death; 66 (3·4%) of 1939 patients allocated to colchicine and 65 (3·3%) of 1942 patients allocated to control experienced hospitalisation or death (hazard ratio [HR] 1·02, 95% CI 0·72-1·43, p=0·93); and 59 (3·0%) of 1945 of patients allocated to aspirin and 73 (3·8%) of 1936 patients allocated to control experienced major thrombosis, hospitalisation, or death (HR 0·80, 95% CI 0·57-1·13, p=0·21). Results for the primary outcome were consistent in all prespecified subgroups, including according to baseline vaccination status, timing of randomisation in relation to onset of symptoms (post-hoc analysis), and timing of enrolment according to the phase of the pandemic (post-hoc analysis). There were more serious adverse events with colchicine than with control (34 patients [1·8%] of 1939 vs 27 [1·4%] of 1942) but none in either group that led to discontinuation of study interventions. There was no increase in serious adverse events with aspirin versus control (31 [1·6%] vs 31 [1·6%]) and none that led to discontinuation of study interventions. The results provide no support for the use of colchicine or aspirin to prevent disease progression or death in outpatients with COVID-19. Canadian Institutes for Health Research, Bayer, Population Health Research Institute, Hamilton Health Sciences Research Institute, and Thistledown Foundation. For the Portuguese, Russian and Spanish translations of the abstract see Supplementary Materials section.

ECT for Depression May Cut Suicide Risk by Nearly 50%

Back to table of contents Previous article Next article Clinical & ResearchFull AccessECT for Depression May Cut Suicide Risk by Nearly 50%Nick ZagorskiNick ZagorskiSearch for more papers by this authorPublished Online:22 Aug 2022https://doi.org/10.1176/appi.pn.2022.09.7.20AbstractThe study also found that suicide risk reduction was more pronounced in patients with unipolar depression than in patients with bipolar depression.Patients hospitalized for depression who received electroconvulsive therapy (ECT) had a nearly 50% reduced risk of suicide death over the following year versus comparable patients who did not receive ECT. The findings came from a detailed analysis of over 67,000 hospital records from patients seen in psychiatric inpatient units across Ontario, Canada.The analysis, published in Lancet Psychiatry, also found that patients who received ECT were less likely to die from other causes within one year after discharge.The findings provide further evidence that ECT can be a lifesaving treatment for patients with severe depression, said lead author Tyler Kaster, M.D., Ph.D., an assistant professor of psychiatry at the University of Toronto and medical head at the Temerty Centre for Therapeutic Brain Intervention.Kaster and colleagues used Canadian registries to examine the 12-month mortality outcomes of all adults aged 18 and older in Ontario who spent more than three days hospitalized for unipolar or bipolar depression between April 1, 2007, and December 31, 2017. Individuals were included in the analysis multiple times if their hospitalizations occurred more than 12 months apart. The final sample included 67,327 hospital admissions, during which 4,982 patients received ECT.A total of 450 deaths from suicide occurred within 12 months of discharge from the hospital; this included the deaths of 27 people who received ECT (5.84 per 1,000 person-years) and 423 who did not receive ECT (7.26 per 1,000 person-years).After adjusting for more than 100 demographic and medical variables that might influence whether a hospitalized patient would be a good candidate for ECT (such as age, psychotic symptoms, and physical comorbidities), the researchers found that patients who received ECT in the hospital had a 47% reduced risk of suicide death and a 25% reduced risk of any death over 12 months compared with those who did not receive ECT. Additional analysis revealed that suicide risk reduction was more pronounced in patients with unipolar depression than in patients with bipolar depression.Kaster and colleagues estimated that for every 200 hospitalized patients treated with ECT, one suicide will be prevented, which is about the same benefit seen with lithium treatment among people with bipolar disorder. Kaster said that while the number of suicides prevented by ECT may appear low, it is meaningful as suicide is a very rare event.Kaster noted that previous research he conducted also found no evidence that patients hospitalized for depression who received ECT were at an increased risk of serious medical events, compared with patients who did not receive ECT.While ECT is not for every depressed patient, Kaster said he hoped that the medical event and mortality data would provide further support that ECT is a medically safe procedure.“[ECT] is still the most invasive treatment for depression we have and any decision to proceed has to be made very thoughtfully, weighing all the benefits and risks,” he said.This study was supported by the Canadian Institutes for Health Research, Norris Scholars Award, and University of Toronto. ■Resources“Risk of Suicide Death Following Electroconvulsive Therapy Treatment for Depression: a Propensity Score-Weighted, Retrospective Cohort Study in Canada”“Risk of Serious Medical Events in Patients With Depression Treated With Electroconvulsive Therapy: A Propensity Score-Matched Retrospective Cohort Study” ISSUES NewArchived

The influence of regulation of medically assisted reproduction on the risk of hospitalization in the first 2years of life.

Do publicly funded fertility treatment and single embryo transfer (SET) result in lower hospitalization rates of children of parents with infertility? Following the 2010 Quebec law introducing free fertility treatment and SET, neonatal intensive care unit (NICU) admissions decreased among all children born to parents with infertility, but not among singletons, whose risk remained slightly higher than that of children of parents without infertility, even accounting for treatment and maternal age. Previous studies reported lower NICU admission rates among children conceived with ART after the 2010 law; however, children conceived without ART by parents with infertility were not considered. Cohort study of children born in 1997-2017 to patients evaluated for infertility ('exposed') at an academic fertility center in Montreal (Canada) in 1996-2015. A random sample of births to Montreal residents served as comparison. Outcomes were identified from Quebec administrative databases. We compared children's healthcare utilization before and after the 2010 law in 6273 exposed and 12583 randomly sampled births (6846 and 12775 children, respectively). We repeated the analysis among children conceived in the 63 months before and after the law ('restricted period'), and examined whether differences in twinning, fertility treatment, and maternal age explained the higher risk of NICU admission among children of parents with infertility. In the exposed cohort, the proportion of twin births and of several adverse outcomes declined after the law. NICU admission and duration of NICU stay decreased overall, but not in singletons. Both measures remained higher in exposed children. Except for NICU admission, hospitalization rates were similar in exposed and random sample children. After accounting for fertility treatment and maternal age, exposed singletons were 17% more likely to be admitted to the NICU than children of parents with no medical history of infertility. Sample size was relatively small; infertile patients were from a single center and the random sample from one city. Despite some limitations, administrative databases are likely to accurately reflect healthcare utilization. Universal access to treatment and, particularly, SET results in an overall reduction of adverse outcomes among children conceived with treatment; however, children of parents with infertility are at a slightly higher risk, regardless of treatment. This study was funded by the Canadian Institutes for Health Research (CIHR, grant no. 123362). No competing interests. N/A.

Risk factors and communities disproportionately affected by cervical cancer in the Russian Federation: A national population-based study.

SummaryBackgroundCervical cancer is one of the leading causes of cancer in women of childbearing age worldwide. A substantial fraction of cervical cancer is associated with Human Papilloma Virus (HPV) infection and is preventable through vaccination and screening. The aim of the study is to describe geographic and epidemiologic trends in incidence and mortality of cervical cancer in Russia during 2007–2018.MethodsPublicly accessible data from the P.A. Herzen Moscow Oncology Research Institute and the Ministry of Health of Russian Federation for 2007–2018 was used for this study. Cervical cancer incidence and mortality rates were analyzed using descriptive statistics and results were mapped to determine the geographic distribution. Potential contributing risk factors in the population were studied using univariate and multivariate Poisson regression analyses.FindingsA total of 187,013 patients were diagnosed with cervical cancer in Russia between 2007 and 2018. The average age-standardized incidence (ASIR) and mortality rates (ASMR) were 15.70/100,000 and 5.76/100,000 females, respectively, with a 27% increase in the incidence observed between 2007 and 2018. The highest ASIR was observed in the Far Eastern Federal District and the lowest in the Central Federal District. Multivariate model for cervical cancer ASIR showed that daily smoking (p = 0·0003) and syphilis (p = 0.003) were significantly associated with cervical cancer incidence.InterpretationThe incidence of cervical cancer in Russia is rising at a significant pace. This trend can in part be attributed to a lack of nationwide cervical cancer screening . The presented results are valuable for informing public health policy on HPV vaccinations, smoking prevention and cervical cancer screening as urgent interventions are needed to combat a troubling trend.FundingThis work was supported by the Cancer Research Society (CRS)-Canadian Institutes for Health Research (CIHR) Partnership Grant #25343 to Dr. Litvinov. Canadian Dermatology Foundation research grant to Dr. Litvinov, and by the Fonds de la recherche du Québec – Santé to Dr. Sasseville (#22648) and to Dr. Litvinov (#34753 and #36769). This research was further supported by the CIHR Catalyst Grant #428712 to Dr. Litvinov.

Differential localization and kinetics of antiviral CD8 T cell responses to chronic and acute murine norovirus infections from initiation onwards

Abstract Recent global events have highlighted the need to better understand mucosal antiviral immunity. Murine Norovirus (MNV) is small non-enveloped positive sense RNA virus that can be used as a model of intestinal viral infection. In this work we use two highly related MNV strains with distinct biological behaviors; CR6 establishes chronic colonic infection, while CW3 establishes systemic infection initiated in the small intestine and is cleared by day 8, correlating with the peak of cell-mediated adaptive immunity. Using flow cytometry and quantitative immunofluorescent microscopy (QIM) of transgenic P14 CD8 T cells specific to recombinant CR6gp33 and CW3gp33, we characterized CD8 T cell responses to CR6 and CW3 from initiation to clearance of CW3. Our data indicate that initiation of CD8 T cell division in response to CR6 infection is delayed, less robust, and largely limited to the mesenteric lymph nodes (MLNs) with less splenic division compared to CW3 infection. Further, the biogeography of P14 T cell priming differs, as early T cell expansion was restricted to distinct nodes of the MLN complex. These early differences propagate out to the time of CW3 clearance. By day 8, there is differential localization of P14 cells in the GI tract to the site of highest viral load and a larger systemic population of P14 cells following CW3 infection. Infection of MLN-deficient mice revealed a critical role for MLN surveillance in targeting P14 T cells to the GI tract following CR6 infection while the spleen plays a compensatory role in response to CW3. These results show how distinct infectious locations of a continuous mucosal surface influence the responses of antiviral CD8 T cells without confounding effects of antigenicity. This work is supported by the Canadian Institutes for Health Research (CIHR) and a UBC 4 Year Fellowship awarded to Blair K Hardman

A dietary fiber limits autoimmune neuroinflammation by restricting Th1 activation, polarization, and migration

Abstract Dietary fibers and their breakdown products have been shown to limit inflammation in multiple disease contexts. However, the term “dietary fiber” encompasses a biochemically diverse family of carbohydrates, and it remains unknown how different fiber sources influence immune cell function. To address this question, we assessed the immunomodulatory capacity of different fiber types in a mouse model of multiple sclerosis, experimental autoimmune encephalomyelitis (EAE). C57BL/6 mice were fed a control diet (5% cellulose) or diets enriched (30%) with resistant starch, inulin, pectin, or guar gum for 2 weeks prior to EAE induction. A diet rich in guar gum uniquely ameliorated the clinical, pathological, and immunological features of EAE. Limited central nervous system (CNS) infiltration of IFNγ+CD4+ T cells (Th1s) in guar gum-fed mice could be attributed to T cell-intrinsic impairment Th1 activation and polarization. Nanostring nCounter transcriptional analyses revealed downregulation of migration-associated markers in CD4+ T cells isolated from guar gum/EAE mice, which was supported by reduced cell-surface expression of integrins involved in migration into the CNS. Functionally, this translated to limited migration of guar gum-derived encephalitogenic Th1s into the CNS upon adoptive transfer into control-fed recipients, which reduced incidence and severity of EAE. However, the 16S rRNA microbiome signature and short chain fatty acid profiles were not unique in comparison to other fiber-supplemented diets, indicating a novel mechanism of action from those previously ascribed in high fiber diet studies. These data confirm the individuality of dietary fibers and identify a novel immunomodulatory function of guar gum. This project was supported by the endMS doctoral studentship program (Multiple Sclerosis Society of Canada) (NMF, JRA), the Canadian Institutes for Health Research (PJT-148909), and the Canada Research Chair program (LCO).

Risk of suicide death following electroconvulsive therapy treatment for depression: a propensity score-weighted, retrospective cohort study in Canada

Previous studies examining the risk of suicide death after treatment with electroconvulsive therapy have been confounded and the resulting uncertainty around the risk-benefit profile of electroconvulsive therapy might contribute to its underuse. We aimed to compare the risk of death by suicide after psychiatric hospitalisation among individuals with depression who had been exposed to electroconvulsive therapy with those who had not. This was a propensity score-weighted, retrospective cohort study using linked population-level administrative health data for adults with depression who had been admitted to a designated psychiatric bed in Ontario, Canada for more than 3 days between April 1, 2007 and Dec 31, 2017. Electroconvulsive therapy exposure was defined as one or more physician billing procedure codes during hospitalisation. The primary outcome was death by suicide identified using administrative health records within 365 days following discharge. We used cause-specific Cox proportional hazards model to estimate the cause-specific hazard ratio (csHR) for electroconvulsive therapy-exposed and electroconvulsive therapy-unexposed individuals. Secondary outcomes were non-suicide death and all-cause mortality. In the analytic cohort, there were 67 327 psychiatric hospitalisation records (27 231 men and 40 096 women; mean age 45·1 years [SD 16·8; range 18-103]), of whom 4982 were exposed to electroconvulsive therapy and 62 345 were not exposed to electroconvulsive therapy. No ethnicity data were available. In propensity-score weighted analyses, electroconvulsive therapy was associated with a significantly reduced risk of suicide death (csHR 0·53 [95% CI 0·31-0·92]). Accounting for non-suicide death as a competing risk had no effect on the findings. Electroconvulsive therapy was also associated with a significantly reduced risk of all-cause mortality (0·75 [0·58-0·97]), but not non-suicide death (0·83 [0·61-1·12]). Among individuals admitted to hospital with depression, electroconvulsive therapy is associated with a significantly reduced risk of death by suicide in the year after discharge. This study reinforces the importance of electroconvulsive therapy, particularly for people with severe depression. Norris Scholars Award, Department of Psychiatry, University of Toronto, and the Canadian Institutes for Health Research.

Differential parathyroid and kidney Ca2+-sensing receptor activation in autosomal dominant hypocalcemia 1.

SummaryBackgroundParathyroid Ca2+-sensing receptor (CaSR) activation inhibits parathyroid hormone (PTH) release, while activation of renal CaSRs attenuates Ca2+ transport and increases expression of the pore-blocking claudin-14. Patients with autosomal dominant hypocalcemia 1 (ADH1), due to activating CASR mutations, exhibit hypocalcemia but not always hypercalciuria (elevated Ca2+ in urine). The latter promotes nephrocalcinosis and renal insufficiency. Although CaSRs throughout the body including the kidney harbor activating CASR mutations, it is not understood why only some ADH1 patients display hypercalciuria.MethodsActivation of the CaSR was studied in mouse models and a ADH1 patient. In vitro CaSR activation was studied in HEK293 cells.FindingsCldn14 showed blood Ca2+ concentration-dependent regulation, which was absent in mice with kidney-specific Casr deletion, indicating Cldn14 is a suitable marker for chronic CaSR activation in the kidney. Mice with a gain-of-function mutation in the Casr (Nuf) were hypocalcemic with low plasma PTH levels. However, renal CaSRs were not activated at baseline but only after normalizing blood Ca2+ levels. Similarly, significant hypercalciuria was not observed in a ADH1 patient until blood Ca2+ was normalized. In vitro experiments indicate that increased CaSR expression in the parathyroid relative to the kidney could contribute to tissue-specific CaSR activation thresholds.InterpretationOur findings suggest that parathyroid CaSR overactivity can reduce plasma Ca2+ to levels insufficient to activate renal CaSRs, even when an activating mutation is present. These findings identify a conceptually new mechanism of CaSR-dependent Ca2+ balance regulation that aid in explaining the spectrum of hypercalciuria in ADH1 patients.FundingErasmus+ 2018/E+/4458087, the Canadian Institutes for Health research, the Novo Nordisk Foundation, the Beckett Foundation, the Carlsberg Foundation and Independent Research Fund Denmark.

Effect of unmanned aerial vehicle (drone) delivery on blood product delivery time and wastage in Rwanda: a retrospective, cross-sectional study and time series analysis

The accessibility of blood and blood products remains challenging in many countries because of the complex supply chain of short lifetime products, timely access, and demand fluctuation at the hospital level. In an effort to improve availability and delivery times, Rwanda launched the use of drones to deliver blood products to remote health facilities. We evaluated the effect of this intervention on blood product delivery times and wastage. We studied data from 20 health facilities between Jan 1, 2015, and Dec 31, 2019, in Rwanda. First, we did a cross-sectional comparison of data on emergency delivery times from the drone operator collected between March 17, 2017, and Dec 31, 2019, with two sources of estimated driving times (Regional Centre for Blood Transfusion estimates and Google Maps). Second, we used interrupted time series analysis and monthly administrative data to assess changes in blood product expirations after the commencement of drone deliveries. Between March 17, 2017, and Dec 31, 2019, 12 733 blood product orders were delivered by drones. 5517 (43%) of 12 733 were emergency orders. The mean drone delivery time was 49·6 min (95% CI 49·1 to 50·2), which was 79 min faster than existing road delivery methods based on estimated driving times (p<0·0001) and 98 min faster based on Google Maps estimates (p<0·0001). The decrease in mean delivery time ranged from 3 min to 211 min depending on the distance to the facility and road quality. We also found a decrease of 7·1 blood unit expirations per month after the start of drone delivery (95% CI -11·8 to -2·4), which translated to a 67% reduction at 12 months. We found that drone delivery led to faster delivery times and less blood component wastage in health facilities. Future studies should investigate if these improvements are cost-effective, and whether drone delivery might be effective for other pharmaceutical and health supplies that cannot be easily stored at remote facilities. Canadian Institutes for Health Research.

Aerosol delivery, but not intramuscular injection, of adenovirus-vectored tuberculosis vaccine induces respiratory-mucosal immunity in humans.

BackgroundAdenovirus-vectored (Ad-vectored) vaccines are typically administered via i.m. injection to humans and are incapable of inducing respiratory mucosal immunity. However, aerosol delivery of Ad-vectored vaccines remains poorly characterized, and its ability to induce mucosal immunity in humans is unknown. This phase Ib trial evaluated the safety and immunogenicity of human serotype-5 Ad-vectored tuberculosis (TB) vaccine (AdHu5Ag85A) delivered to humans via inhaled aerosol or i.m. injection.MethodsThirty-one healthy, previously BCG-vaccinated adults were enrolled. AdHu5Ag85A was administered by single-dose aerosol using Aeroneb Solo Nebulizer or by i.m. injection. The study consisted of the low-dose (LD) aerosol, high-dose (HD) aerosol, and i.m. groups. The adverse events were assessed at various times after vaccination. Immunogenicity data were collected from the peripheral blood and bronchoalveolar lavage samples at baseline, as well as at select time points after vaccination.ResultsThe nebulized aerosol droplets were < 5.39 μm in size. Both LD and HD of AdHu5Ag85A administered by aerosol inhalation and i.m. injection were safe and well tolerated. Both aerosol doses, particularly LD, but not i.m., vaccination markedly induced airway tissue–resident memory CD4+ and CD8+ T cells of polyfunctionality. While as expected, i.m. vaccination induced Ag85A-specific T cell responses in the blood, the LD aerosol vaccination also elicited such T cells in the blood. Furthermore, the LD aerosol vaccination induced persisting transcriptional changes in alveolar macrophages.ConclusionInhaled aerosol delivery of Ad-vectored vaccine is a safe and superior way to elicit respiratory mucosal immunity. This study warrants further development of aerosol vaccine strategies against respiratory pathogens, including TB and COVID-19.Trial registrationClinicalTrial.gov, NCT02337270.FundingThe Canadian Institutes for Health Research (CIHR) and the Natural Sciences and Engineering Research Council of Canada funded this work.

Development and validation of a risk calculator for major mood disorders among the offspring of bipolar parents using information collected in routine clinical practice.

BackgroundFamily history is a significant risk factor for bipolar disorders (BD), but the magnitude of risk varies considerably between individuals within and across families. Accurate risk estimation may increase motivation to reduce modifiable risk exposures and identify individuals appropriate for monitoring over the peak risk period. Our objective was to develop and independently replicate an individual risk calculator for bipolar spectrum disorders among the offspring of BD parents using data collected in routine clinical practice.MethodsData from the longitudinal Canadian High-Risk Offspring cohort study collected from 1996 to 2020 informed the development of a 5 and 10-year risk calculator using parametric time-to-event models with a cure fraction and a generalized gamma distribution. The calculator was then externally validated using data from the Lausanne–Geneva High-Risk Offspring cohort study collected from 1996 to 2020. A time-varying C-index by age in years was used to estimate the probability that the model correctly classified risk. Bias corrected estimates and 95% confidence limits were derived using a jackknife resampling approach.FindingsThe primary outcome was age of onset of a major mood disorder. The risk calculator was most accurate at classifying risk in mid to late adolescence in the Canadian cohort (n = 285), and a similar pattern was replicated in the Swiss cohort (n = 128). Specifically, the time-varying C-index indicated that there was approximately a 70% chance that the model would correctly predict which of two 15-year-olds would be more likely to develop the outcome in the future. External validation within a smaller Swiss cohort showed mixed results.InterpretationFindings suggest that this model may be a useful clinical tool in routine practice for improved individualized risk estimation of bipolar spectrum disorders among the adolescent offspring of a BD parent; however, risk estimation in younger high-risk offspring is less accurate, perhaps reflecting the evolving nature of psychopathology in early childhood. Based on external validation with a Swiss cohort, the risk calculator may not be as predictive in more heterogenous high-risk populations.FundingThe Canadian High-Risk Study has been funded by consecutive operating grants from the Canadian Institutes for Health Research, currently CIHR PJT Grant 152796 he Lausanne-Geneva high-risk study was and is supported by five grants from the Swiss National Foundation (#3200–040,677, #32003B-105,969, #32003B-118,326, #3200–049,746 and #3200–061,974), three grants from the Swiss National Foundation for the National Centres of Competence in Research project “The Synaptic Bases of Mental Diseases” (#125,759, #158,776, and #51NF40 – 185,897), and a grant from GlaxoSmithKline Clinical Genetics.