Canada Registry Research Articles

QOL-44. EARLY SEVERE HEARING LOSS IN CANADIAN CHILDREN WITH CENTRAL NERVOUS SYSTEM TUMORS: A POPULATION-BASED COHORT STUDY

Abstract BACKGROUND Severe treatment-related hearing loss (HL) is associated with devastating psychosocial/neurocognitive outcomes. Children with central nervous system (CNS) tumors are highly vulnerable to severe HL due to tumor location and treatment exposures. This is the first study to report national CNS tumor-specific rates and predictors of early severe HL. METHODS We conducted a retrospective, population-based cohort study of all children ≤15yrs at diagnosis with CNS tumors between 2001-2019 using the Cancer in Young People in Canada registry. The primary outcome was Common Terminology Criteria for Adverse Events grade 3/4 HL ≤5yrs following diagnosis. We determined prevalence and probabilities of early HL; predictors were determined using multivariable logistic regression models. RESULTS Among 3,201 children with CNS tumors, 5.1% experienced early HL. Children with medulloblastoma (N=570) and ATRT/other embryonal tumors (N=269) experienced disproportionate rates (16.1%, 15.2%, respectively); 85.4% (medulloblastoma) and 68.8% (ATRT/other embryonal) received cisplatin, 74.6% (medulloblastoma) and 52.1% (ATRT/other embryonal) were irradiated. In children with medulloblastoma, when controlling for follow-up, age <=5yrs at diagnosis [odds ratio (OR) 2.4, 1.5-3.8], radiation (OR 3.5, 1.6-7.6), and cisplatin (OR 20.4, 1.3-329.7) predicted early HL. In children with medulloblastoma post cisplatin, age ≤5yrs at diagnosis doubled the probability of early HL in both irradiated (29.8%, vs 15.3% if >5yrs at diagnosis) and non-irradiated patients (10.6% vs 4.8% if >5yrs at diagnosis). In children with ATRT/other embryonal, cisplatin (OR 28.2, 1.7-472.1) was the only predictor of early HL. CONCLUSIONS In the largest population-based study of early severe HL in children with CNS tumors, we report striking rates in children with embryonal tumors. Younger irradiated children had disproportionate probabilities of early HL, suggesting a novel additive interaction between age at diagnosis and radiation. Standardized otoprotection and research focusing on therapy de-escalation in young children with embryonal tumors are urgently needed.

Epidemiology of Pediatric Tumors in Quebec: A 17-Year Report of Cancer in Young People in the Canada Registry.

Cancer is the leading cause of disease-related death among children of more than 1 year of age. However, childhood cancer risk factors and etiology are yet to be fully understood. The goal of this study is to identify geographic variation among children and adolescents diagnosed with pediatric tumors between 2001 and 2018 in the province of Quebec. We analyzed pediatric patients less than 15 years of age from the Cancer in Young People in Canada (CYP-C) surveillance system who were diagnosed between 2001 and 2018 with cancer in the province of Quebec. The age-standardized age-adjusted incidence rates (AAIR) per 100,000 person years were calculated for all childhood cancers by cancer subgroups, Quebec Health regions, and age groups. Overall, 3904 pediatric patients less than 15 years old were diagnosed with cancer in the province of Quebec in 2001-2018. The overall incidence rate (IR) in the province of Quebec was 16.14 (95%CL [15.56-16.73]) per 100,000 person years. For childhood cancers, regions that presented a higher AAIR were Chaudière-Appalaches and Capitale-Nationale with 18.2 and 17.5 per 100,000 person years, respectively. The incidence rates (IRs) in Chaudière-Appalaches (95% CI 1.0439-1.3532) and in Capitale-Nationale (95% CI 1.0124-1.2942) were statistically higher than the incidence in the province of Quebec (p = 0.0090 and p = 0.0310, respectively). When comparing the AAIR of the CNS tumor subgroup in Chaudière-Appalaches and in Capitale-Nationale, with the provincial average, we noticed a statistically higher incidence in Chaudière-Appalaches and a trend for Capitale-Nationale (p < 0.0001 and p = 0.0602, respectively). There is evidence of spatial clusters in Chaudière-Appalaches and Capitale-Nationale as areas for all childhood cancers. Further studies should be performed to investigate potential risk factors in these regions.

The GLA:D® Canada program for knee and hip osteoarthritis: A comprehensive profile of program participants from 2017 to 2022.

The Good Life with osteoArthritis in Denmark (GLA:D®) program was implemented in Canada in 2017 with the aim of making treatment guideline-recommended care available to the 4 million Canadians with knee and hip osteoarthritis (OA). This report describes the GLA:D® Canada program, registry and data collection procedures, and summarizes the sociodemographic and clinical profile of participants with knee and hip OA to inform the scientific research community of the availability of these data for future investigations and collaborations. The GLA:D® program consists of three standardized components: a training course for health care providers, a group-based patient education and exercise therapy program, and a participant data registry. Patients seeking care for knee or hip OA symptoms and enrolling in GLA:D® are given the option to provide data to the GLA:D® Canada registry. Participants agreeing to provide data complete a pre-program survey and are followed up after 3-, and 12-months. Data collected on the pre-program and follow-up surveys include sociodemographic factors, clinical characteristics, health status measures, and objective physical function tests. These variables were selected to capture information across relevant health constructs and for future research investigations. At 2022 year-end, a total of 15,193 (11,228 knee; 3,965 hip) participants were included in the GLA:D® Canada registry with 7,527 (knee; 67.0%) and 2,798 (hip; 70.6%) providing pre-program data. Participants were 66 years of age on average, predominately female, and overweight or obese. Typically, participants had knee or hip problems for multiple years prior to initiating GLA:D®, multiple symptomatic knee and hip joints, and at least one medical comorbidity. Before starting the program, the average pain intensity was 5 out of 10, with approximately 2 out of 3 participants using pain medication and 1 in 3 participants reporting a desire to have joint surgery. Likewise, 9 out 10 participants report having previously been given a diagnosis of OA, with 9 out 10 also reporting having had a radiograph, of which approximately 87% reported the radiograph showed signs of OA. We have described the GLA:D® Canada program, registry and data collection procedures, and provided a detailed summary to date of the profiles of participants with knee and hip OA. These individual participant data have the potential to be linked with local health administrative data registries and comparatively assessed with other international GLA:D® registries. Researchers are invited to make use of these rich datasets and participate in collaborative endeavours to tackle questions of Canadian and global importance for a large and growing clinical population of individuals with hip and knee OA.

Familial hypercholesterolemia in Canada: Investigating management patterns and clinical outcomes from the FH Canada registry

Familial hypercholesterolemia in Canada: Investigating management patterns and clinical outcomes from the FH Canada registry

A Clinically Validated Genetic Screening for Familial Hypercholesterolemia in Quebec

Lead Author's Financial Disclosures Nothing to disclose. Study Funding None. Background/Synopsis Familial Hypercholesterolemia (FH) is the most common genetic disorder in humans with an estimated prevalence of 1/311. In geographic regions with founder effect mutations, such as the province of Quebec, Canada, prevalence is as high as 1/80. FH is associated with premature atherosclerotic cardiovascular disease (ASCVD) caused by elevated low-density lipoprotein cholesterol (LDL-C). Although early diagnosis and therapy of FH can normalize life expectancy, less than 15% of cases are diagnosed. Cascade screening and genetic testing aim to improve diagnosis, treatment, and outcomes in FH. Objective/Purpose Determine the impact of unbiased genetic testing in re-classification of patients with a clinical diagnosis of FH in Quebec, in comparison with the existing genetic panel offered by Quebec's Ministry of Health and Social Services (Ministere de la Sante et des Services Sociaux (MSSS)). Methods A retrospective cohort study was conducted on patients seen in the Preventive Cardiology/Lipid Clinic of the McGill University Health Center (MUHC) at the Royal Victoria Hospital in Montreal, Quebec, Canada, between September 2017 to September 2021. The MUHC Preventive Cardiology/Lipid clinic is one of the 19 academic FH Canada Registry participating sites. Here, we report a single-center experience with the only clinically validated molecular genetic screening for FH (CLIA compliant) in Canada. We performed next-generation sequencing of the LDLR, APOB, and PCSK9 genes and multiplex ligation-dependent probe amplification (MLPA) of the LDLR gene to detect genetic mutations and copy number variants. All mutations were reviewed by a geneticist and cross-referenced in ClinVar. Results Between 2018-2021, we examined 369 FH cases (57% males, 43% females) based on the Canadian FH definition clinical criteria. For index patients, mean age at diagnosis was 40+/- 16 years, while 30+/-16 years was for cascade screening patients. Baseline (untreated) LDL-C was 6.5+/-2.0 mmol/L. In 224 patients who underwent genetic testing, a pathogenic mutation was identified in 167 (75%) individuals, in keeping with ∼20% of FH patients with a polygenic form. A majority of affected patients had mutations in the LDLR (87%) or APOB (13%) genes. Interestingly, the genetic panel offered by Quebec's Health Ministry, which includes 10 common mutations in French Canadians, only accounted for 46% of identified mutations. Even in patients self-describing as French Canadians, more than 20% did not have a common mutation. We subsequently examined the impact of genetic testing in re-classification of patients' FH diagnosis. Interestingly, genetic screening identified a genetic variant in 26% of patients initially classified as 'severe hypercholesterolemia' and allowed for 85 (75%) of patients initially diagnosed as 'probable FH' to be re-classified as 'definite FH'. Conclusions Genetic testing in patients suspected of having FH provides diagnostic certainty and permits re-classification of individuals with a diagnosis of 'severe hypercholesterolemia' or 'probable FH' according to current definitions. Furthermore, the limited genetic panel offered by the province of Quebec, focusing on common French-Canadian mutations, provides incomplete data in the majority of cases. We therefore propose that most patients with a presumptive diagnosis of FH undergo an unbiased genetic analysis. This allows for increased identification of FH patients and can help reduce burden of ASCVD and death in Canadians with FH. Furthermore, this study has important implications on cascade screening, public health policies and reimbursement of drugs such as PCSK9 inhibitors. Nothing to disclose.

Venous Thrombotic Events Are Independently Associated with Inferior Survival Outcome in Pediatric Cancer Patients: A Multicenter Study

Background: Venous thrombotic events (VTE) are well recognized complications in pediatric oncology patients. Although risk factors for VTE have been studied the association of VTE with survival in pediatric cancer patients has not been well studied. We hypothesized that pediatric oncology patients who experienced VTE have significantly inferior survival outcome as compared to patients who did not experience VTE.Aim: To determine the association of VTE with survival outcome in pediatric oncology patients.Methods: The population studied were oncology patients from 2000-2015 in Atlantic Canada: 3 Maritime provinces (population= 1.8 million) and from the province of Newfoundland and Labrador (population= 530,000). All pediatric oncology patients from the Maritimes (Nova Scotia, New Brunswick and Prince Edward Island) are treated at the IWK Health Centre (IWK) in a shared care model with regional provincial hospitals. All pediatric oncology patients in Newfoundland and Labrador are treated at the Janeway Children's Health and Rehabilitation Centre (Janeway). This provided a population-based cohort of the total pediatric oncology patients in the 4 Atlantic provinces. Research Ethics Board approval was obtained from each institution.A database of all pediatric oncology patients treated at the IWK was created by amalgamating data from (i) Pediatric oncology hospital database (ii) Cancer in Young People in Canada registry (CYP-C) (iii) pharmacy database and (iv) hospital health records. A database of pediatric oncology patients treated at the Janeway was amalgamated from (i) Janeway written logs (ii) Hospital health records and (iii) CYP-C.Data on patient demographics, diagnosis and date of diagnosis were extracted. Status of every patient, date of last visit or date of death, on or up to December 31, 2015 was reviewed. Brain tumor patients were excluded due to the low incidence of thrombosis.The association between VTE and survival was examined using Kaplan-Meier plots and Cox Proportional Hazards regression. An exploratory survival tree analysis indicated an interaction between cancer type and VTE, and the analysis was therefore stratified by cancer type as group 1: leukemia, lymphoma, other and group 2: sarcoma. Models were adjusted for sex and age at diagnosis. The statistical analysis was performed using R version 3.3.2 and RStudio version 1.0.136.Results: Of the 943 patients included in the study, 70 were diagnosed with thrombosis (7%). The prevalence of thrombosis in group 1 and 2 was 6.9% (n=56) and 10% (n=14) respectively. Cancer types included leukemia (n=356, 38%), lymphoma (n=154, 16%), sarcoma (n=137, 15%), and other (n=296, 31%). Overall mortality was 14%. No patient died directly from VTE. Kaplan-Meier plots showed a showed inferior survival in the presence of VTE in patients in both groups 1 and 2 (Figure 1). Cox proportional hazard model showed a significantly decreased survival for patients in group 1 with a VTE (p<0.001), group 2 without a VTE (p<0.001) and group 2 with a VTE (p<0.001) as compared to patients in group 1 without VTE (Table 1). Patients with a sarcoma did not show a significant difference in patients with and without a VTE due to the overlapping confidence interval (with VTE CI: 4.53 to 20.75, without VTE CI 2.48 to 5.62). Age at diagnosis (p=0.498) and sex (p=0.300) were not associated with survival.Conclusion: In the present study, we demonstrated in a large multi-center population-based cohort of pediatric oncology patients that the survival outcome of patients with leukemia, lymphoma and other types of cancers who develop a VTE is significantly inferior as compared to that of patients who do not develop a VTE. Patients with sarcoma who developed a VTE showed a decrease in survival as compared to those who did not develop VTE. However the results were not statistically significant likely due to the small sample size of these patients. The role of possible confounders such as treatment intensity, chemotherapeutic agents, and central venous catheters were not assessed in the preset study but would be included in future research. Further larger studies are necessary to understand the association between VTE and survival outcome in pediatric oncology patients and determine the prognostic impact of VTE in them. [Display omitted] DisclosuresMoorehead:Baxalta: Honoraria, Speakers Bureau; Bayer: Honoraria; Pfizer: Speakers Bureau; Octapharma: Honoraria; Bioverativ: Honoraria.

First Biologic Drug Persistence in Patients With Ankylosing Spondylitis and Nonradiographic Axial Spondyloarthritis: A Real-World Canadian Physicians' Experience.

Data were obtained from persons enrolled in the SpondyloArthritis Research Consortium of Canada registry between 2003 and 2018. Kaplan-Meier curves were constructed from the time of biologic initiation until discontinuation and compared using the log-rank test. Subanalyses were performed according to calendar year and disease activity. Cox proportional hazards models were used to identify factors associated with discontinuation. We identified 385 biologic-naive persons. Overall, the 349 AS participants had longer persistence to their first biologic than the 36 nr-axSpA subjects (p < 0.01). The Bath Ankylosing Spondylitis Disease Activity Index and Bath Ankylosing Spondylitis Functional Index decreased by 2.3 points (95% confidence interval [CI], 1.9-2.7) and 3.2 points (95% CI, 2.6-3.7), respectively, in the first year and were stable thereafter. Adjusting for sex, human leukocyte antigen B27, and smoking status, nr-axSpA patients were more likely to discontinue their biologic than AS patients (hazards ratio, 1.65; 95% CI, 1.03-2.62). In this real-world study, AS patients had longer persistence to their first biologic compared with nr-axSpA, with disease subtype being the most significant predictor of treatment persistence. Future studies should be targeted at assessing long-term clinical outcome of axSpA in the real-world setting.

Long-term effectiveness and safety of infliximab, golimumab and ustekinumab in patients with psoriatic arthritis from a Canadian prospective observational registry

ObjectivesThe objectives of this study were to describe the demographic profile and baseline disease characteristics of patients with psoriatic arthritis (PsA) treated with either infliximab (IFX), subcutaneous golimumab (GLM) or...

Use of Tissue Plasminogen Activator as a Surrogate Measure for Central Venous Catheter Dysfunction and Survival Outcome in Children with Cancer: A Population-Based Retrospective Cohort Study

Central venous catheter (CVC) dysfunction is often associated with thrombosis, which in turn has been linked with poorer survival outcomes in cancer patients. Our objective was to examine the association of tissue plasminogen activator (tPA) administration as a surrogate measure of CVC dysfunction with survival in pediatric cancer patients. The present study uses data from a population-based retrospective cohort of pediatric oncology patients from the Canadian Maritime provinces treated between 2000 and 2017 at the IWK Health Centre, Halifax, NS. Demographics, diagnosis, date of death or date of last visit, and tPA use for CVC dysfunction were obtained from clinical databases and the provincial Cancer in Young People in Canada registry. The association between tPA administration and survival was examined using a Cox regression model adjusted for sex, age at diagnosis, cancer type, thrombosis, CVC duration, diagnosis era, and treatment modalities. Out of 821 patients, 206 received one or more doses of tPA during upfront therapy. The death rate was 21% and 15% respectively in patients who did and did not receive tPA. In the adjusted regression model, after receiving one or more doses of tPA, children had significantly poorer survival as compared to those that did not receive tPA (HR: 1.496, 95% CI: 1.019, 2.197). CVC dysfunction may be associated with a poorer prognosis in pediatric cancer patients. Future studies should corroborate these findings in other populations, examine the influence of other potential confounders, and determine the role of CVC dysfunction in prognostic models of cancer survival.

Safety and Performance of the Orsiro Sirolimus-Eluting Stent in the Treatment of All-Comers Patient Population in Daily Clinical Practice

BackgroundThe BIOFLOW-III Canada registry aimed to evaluate the safety and efficacy of Orsiro sirolimus-eluting stents (SES) with biodegradable polymer, in an all-comers patient population. MethodsWe conducted a prospective, non-randomized, multi-center, observational all-comers registry of patients undergoing percutaneous coronary intervention (PCI) with Orsiro SES at two high-volume Canadian centers. The primary endpoint was one-year target lesion failure (TLF) defined as a composite of cardiac death, target-vessel myocardial infarction (MI), coronary artery bypass grafting and clinically driven target lesion revascularization. Four subgroups were pre-defined: i) diabetic patients; ii) small vessels (≤2.75 mm); iii) chronic total occlusions (CTO) and iv) acute MI. ResultsFrom May 2014 to July 2016, 250 patients (mean age 66.2 ± 10.8 years, 75.6% males, 30% diabetes) underwent PCI with Orsiro SES for 385 coronary lesions. The mean stent diameter was 2.98 ± 0.50 mm and the mean stent length was 22 ± 8 mm. Clinical device and procedural success rates were with 99.5% and 97.6%, respectively. The overall one-year TLF rate was 2.8% [95% confidence interval (CI) 1.4–5.8%], whereas TLF rates were 4.1% [95%CI 1.3–12.2%], 3.2% [95%CI 1.2–8.4%], 8.3% [95%CI 2.2–29.4%], and 2.6% [95%CI 0.7–9.9%] in patients with diabetes, small vessels, CTO, and acute MI, respectively. One case of possible stent thrombosis (ST) was reported (0.4% [95%CI 0.1–2.8%]), while no cases of definite/probable ST was observed at one year. ConclusionOur data provide further evidence of the safety and clinical performance of Orsiro SES in an unselected, real-world, complex patient population. Condensed abstractThe BIOFLOW-III Canada registry is a prospective, non-randomized, multi-center, observational all-comers registry designed to evaluate the safety and performance of the Orsiro SES in non-selected, real-world patients. A total of 250 patients (mean age 66.2 ± 10.8 years, 75.6% males, 30% diabetes) who underwent PCI with Orsiro SES, were enrolled at two high-volume Canadian centers. The overall rate of TLF at one year was 2.8% [95%CI 1.4–5.8%], whereas TLF rates were 4.1%, 3.2%, 8.3%, and 2.6% in patients with diabetes, small vessels ≤2.75 mm, CTO, and acute MI, respectively. No case of definite/probable ST was observed.

Diabetes is associated with an increased risk of cardiovascular disease in patients with familial hypercholesterolemia

Familial hypercholesterolemia (FH) is the most common genetic disorder of lipoprotein metabolism, affecting 1:250 individuals worldwide. This monogenic disease is associated with lifelong elevation in circulating low-density lipoprotein cholesterol and premature cardiovascular disease (CVD). In 2016, the estimated prevalence of diabetes in Canada was 9%. In the FH population, little is known about the prevalence of diabetes and its impact on CVD risk. The objectives of this study were to investigate the prevalence of diabetes among a large cohort of FH patients and to investigate the association between diabetes and CVD risk. The FH Canada registry contains data on 3740 subjects. We selected adult patients with FH according to the Dutch Lipid Clinic Network criteria. After excluding subjects with missing data, there remained 1412 patients who were included in the final analysis. The present cohort from the FH Canada database comprises a total of 73 diabetic patients (5%). The prevalence of CVD was higher in diabetic FH patients (45%) than in nondiabetics (22%) (odds ratio 2.9, 95% confidence interval 1.8-4.7, P<.0001). However, the average Montreal-FH-SCORE was also higher in the diabetic group than in the nondiabetic group (29.7 vs 21.2, respectively, P<.0001). Diabetes was no longer a significant predictor of CVD when the analysis was adjusted for the Montreal-FH-SCORE. In conclusion, diabetic FH patients represent a high-risk group for CVD risk, most likely due to the fact that diabetic subjects have many concomitant cardiometabolic risk factors.

Modeling cystic fibrosis disease progression in patients with the rare CFTR mutation P67L

BackgroundThe progression of cystic fibrosis (CF) in patients with the rare mutation P67L was examined to determine if it induced a milder form of CF compared to the common severe ΔF508 mutation. MethodsParameters of lung function, level of bacterial infection, nutritional status and hospitalization were used to represent CF progression. Age at diagnosis and pancreatic status were used to assess CF presentation. Analysis of data from the CF Canada Registry collected over a 15-year period included 266 ΔF508/ΔF508 homozygote patients from CF clinics in Atlantic Canada and 26 compound heterozygote patients with the rare P67L mutation from clinics across Canada. ResultsLate age at diagnosis, high incidence of pancreatic sufficiency, maintained Body Mass Index (BMI) with age, delayed life-threatening bacterial infection, and fewer days in hospital were observed for P67L heterozygote patients included in this study. Although the decline of lung function did not differ from ΔF508 homozygotes, the fact that a greater proportion of P67L heterozygotes live to an older age suggests that lung function is not the primary factor determining CF progression for P67L heterozygote patients. ConclusionThe P67L mutation is associated with a mild disease, even when combined with the severe ΔF508 mutation.

Physician needs and preferences for information about long-term follow-up and care of survivors of childhood cancer.

66 Background: The treatments that childhood cancer survivors (CCS) undergo can lead to an increased risk of other health problems later in life, and risk-based follow-up care is necessary throughout their lifetime. Regrettably, family physicians caring for CCS often report having no record of their patients’ past disease, treatment history, or need for follow-up. As the large majority of CCS will transition from specialized pediatric oncology care to generalized adult care in the community, detailed treatment summaries and Survivorship Care Plans (SCP) are needed to ensure that both the survivor and their care providers are adequately informed of the survivors diagnosis, treatment(s), potential risk for late effects, and long-term surveillance and healthcare needs. This qualitative study sought to explore the needs, preferences, and the perceived utility of SCP for family physicians (FP) caring for CCS. Methods: Using publically available Children’s Oncology Group guidelines, a de-identified sample SCP indicating the diagnosis, treatment(s) received, and follow-up recommendations for a common childhood cancer diagnosis was automatically generated using a newly developed algorithm and patient data from the Cancer in Young People – Canada registry. Semi-structured telephone interviews with six FP that have a known CCS in their practice were then used to gain insight into the FP perceived role in the long-term management and care of CCS, their cancer information needs, concerns with communication, their perceived utility of the SCP, and preferred format(s) for receiving the SCP. The constant comparative method was used for thematic analysis. Results: The key themes emerging from the six completed interviews include a lack of confidence among FP in their ability to care for CCS and a need for additional knowledge and resources. FP also identified psychological barriers to cancer care discussions with CCS and identified a patient need for greater psychological support. Overall, SCP were viewed as helpful. Conclusions: SCP are perceived to be of benefit to FP of CCS as they serve to increase their knowledge of patient diagnosis, treatments received, and suggested risk-based follow-up.

Cancer incidence, morbidity, and survival in Canadian first nation children: A Manitoba population‐based study from the cancer in young people in Canada (CYP‐C) registry

Health disparities between Canadian First Nation (FN) people and the rest of the national population exist. No studies have specifically documented cancer-related health outcomes in Canadian FN children. The purpose of this study was to describe the incidence of pediatric malignancies in Manitoba FN children, and to compare morbidity patterns and survival between FN and non-FN children with cancer in the Canadian province of Manitoba. A retrospective, population-based review of all children (0-14.99 years) diagnosed with malignancy (2001-2008) in Manitoba, Canada was undertaken using the Cancer in Young People in Canada registry. FN children were compared to the non-FN population for markers of morbidity and survival. The average annual age-standardized incidence rate for all childhood cancers in FN children was 132 per 1,000,000 per year. 240 children were included in the morbidity and survival analyses (38 FN; 202 non-FN). No differences were found between FN and non-FN children in time from first presentation of symptoms to consultation with an oncology specialist or diagnosis, or number of hospital admissions / total days of admission for treatment complications. Overall survival was inferior for FN children in univariable analysis (P = 0.048) but not when risk group was included in a multivariable analysis (P = 0.15). No difference in event free survival or cumulative incidence of relapse was identified. The estimated incidence of childhood cancers in the Manitoba FN population is similar to provincial incidence rates. No differences in morbidity patterns or survival were found between Manitoba FN and non-FN children with cancer.

Antenatal risk factors for peanut allergy in children

BackgroundPrenatal factors may contribute to the development of peanut allergy. We evaluated the risk of childhood peanut allergy in association with pregnancy exposure to Rh immune globulin, folic acid and ingestion of peanut-containing foods.MethodsWe conducted a web-based case-control survey using the Anaphylaxis Canada Registry, a pre-existing database of persons with a history of anaphylaxis. A total of 1300 case children with reported peanut allergy were compared to 113 control children with shellfish allergy. All were evaluated for maternal exposure in pregnancy to Rh immune globulin and folic acid tablet supplements, as well as maternal avoidance of dietary peanut intake in pregnancy.ResultsReceipt of Rh immune globulin in pregnancy was not associated with a higher risk of peanut allergy (odds ratio [OR] 0.86, 95% confidence interval [CI] 0.51 to 1.45), nor was initiation of folic acid tablet supplements before or after conception (OR 0.53, 95% CI 0.19 to 1.48). Complete avoidance of peanut-containing products in pregnancy was associated with a non-significantly lower risk of peanut allergy (OR 0.53, 95% CI 0.27 to 1.03).ConclusionThe risk of childhood peanut allergy was not modified by the following common maternal exposures in pregnancy: Rh immune globulin, folic acid or peanut-containing foods.Clinical implicationsRh immune globulin, folic acid supplement use and peanut avoidance in pregnancy have yet to be proven to modulate the risk of childhood anaphylaxis to peanuts.Capsule SummaryIdentification of prenatal factors that contribute to peanut allergy might allow for prevention of this life-threatening condition. This article explores the role of three such factors.

Community-level income inequality and mortality in Québec, Canada

Evidence of the association between income inequality and mortality for small rather than large areas is conflicting. This study evaluated community-level income inequality in relation to age- and cause-specific mortality. Ecological analysis. Mortality data were extracted from the Québec, Canada registry for 1999-2003. For Québec communities (n=143), directly standardized mortality rates were calculated for all-cause (overall, working-age and post-working-age), suicide, alcohol, tobacco and cardiovascular mortality. Using 2001 Canada Census data, the tertiles of income inequality measured as the decile ratio, coefficient of variation and median share were calculated. The relative risk (RR) of death was determined using Poisson regression, accounting for median community income, family structure and rural-urban area. Income inequality was most strongly associated with alcohol-related mortality (RR(CoefficientVariation) 0.85, 95% confidence interval 0.77-0.94), followed by statistically significant but weaker inverse associations with tobacco-related and age-specific all-cause mortality. Income inequality in Québec communities is inversely associated with mortality outcomes, particularly alcohol-related mortality. These associations contrast with positive or null associations observed in studies of larger US and Canadian metropolitan areas, respectively. Community-level studies accounting for individual-level covariates are necessary to clarify the relationship between income inequality and mortality.

Intravenous tissue plasminogen activator for acute ischemic stroke in patients ≥80 years old: The London, Canada experience

P163 Background: Although, elderly patients (≥80 years) are not excluded from receiving tPA for acute ischemic stroke (AIS), uncertainty still exists regarding the effectiveness and safety of tPA in this age group. Objective: To compare baseline characteristics, outcomes, and complications of AIS patients treated with iv tPA aged ≥80 with their younger counterparts (&lt;80). Methods: Patients ≥80 were compared to the younger group aged &lt;80 in the prospective London Canada registry of iv tPA use for AIS. Patients presenting with AIS within three hours of symptom onset were treated according to the 1995 National Institute of Neurological Disorders and Stroke (NINDS) guidelines but excluded if &gt;1/3 middle cerebral artery territory was involved. Findings: To date 62 patients have been treated. Median ages of the young group (n=46) are 68 years (range of 37–79) and of the older group (n=16) are 85 years (range of 80–93). Thirty-one of 46 younger patients and eleven of 16 older patients have reached the 3 month follow-up mark. The elderly group had a statistically significant higher mean pre-stroke Modified Rankin Score (mRS) of 1.5 compared to 0.6 for the younger group (p=0.01). The mean initial National Institutes of Health Stroke Scale Scores (NIHSSS), and mean time to tPA from stroke onset do not differ significantly: 14 (young) and 17 (old) (p=0.07), and 151 minutes (young) and 155 minutes (old) (p=0.67). Percent of patients achieving ≥4 point improvement in NIHSS 24 hours post tPA, a 3 month NIHSS of 0–1, and a 3 month MRS of 0–1 are 63 V.S. 44 (p=0.29), 35 V.S. 36 (p=0.80)and 41 V.S. 9 (p=0.12) for the young and old groups respectively. Only one patient (age 81) had a fatal intracranial hemorrhage (ICH). No other patients in the registry suffered a symptomatic ICH. Of the younger group, 11% and of the elderly group, 19% had an asymptomatic ICH (p=0.71). Conclusions: Despite the elderly patients having greater pre-stroke disability, iv tPA for AIS in this group does not significantly differ in effectiveness and complications compared to the same treatment in patients under age 80. TPA should not be withheld from AIS patients on the basis of age alone.