Kate Bassil

Effectiveness of Public Health Interventions in Reducing Morbidity and Mortality during Heat Episodes: a Structured Review

Increasing concern over the impact of hot weather on health has fostered the development of public health interventions to reduce heat-related health impacts. However, evidence of the effectiveness of such interventions is rarely cited for justification. Our objective was to review peer-reviewed and grey literature evaluating interventions aimed at reducing morbidity and/or mortality in populations during hot weather episodes. Among studies considering public risk perceptions, most respondents were aware when an extreme heat episode was occurring but did not necessarily change their practices, primarily due to a lack of self-perception as vulnerable and confusion about the appropriate actions to be taken. Among studies of health outcomes during and following heat episodes, studies were suggestive of positive impacts in reducing morbidity and mortality. While the limited evaluative work to date suggests a positive impact of public health interventions, concern persists about whether the most vulnerable groups, like the elderly and homeless, are being adequately reached.

The Role of Maps in Neighborhood-Level Heat Vulnerability Assessment for the City of Toronto

Extreme hot weather is a threat to public health, and it is anticipated that the number of hot days and the duration of extreme heat events will increase with climate change. Already, heat-related illness and mortality is the dominant natural hazard in many countries. While everybody is at risk to varying degrees, there are known factors relating to heat exposure and sensitivity that make some population groups more vulnerable than others. The objective of this paper is to assess cartographic design decisions in creating heat vulnerability maps, and how they may affect the usefulness of different map types. Spatial patterns of heat vulnerability were visualized using maps representing individual exposure and sensitivity indicators, composite vulnerability indices, and geographical hot spots of vulnerability. The composite indices were calculated using the ordered weighted averaging (OWA) multi-criteria analysis method. Hot spots were determined using local indicators of spatial association (LISA). This study is part of an ongoing project which aims to identify vulnerable populations within the City of Toronto, Canada, in order to support targeted response and mitigation. The maps were found to be a valuable addition to the hot weather planning toolkit supporting neighborhood-level interventions.

Impact of late preterm and early term infants on Canadian neonatal intensive care units.

OBJECTIVE To examine the short-term morbidities, mortality, and use of neonatal intensive care unit (NICU) resources for late preterm, early term, and term infants. STUDY DESIGN Infants born between 34 and 40 weeks of gestation and admitted to a Canadian NICU in 2010 were designated late preterm (340/7 to 366/7 weeks), early term (370/7 to 386/7 weeks), or term (390/7 to 406/7 weeks). Mortality, short-term morbidities, and resource utilization were compared between the three groups using chi-square tests and analysis of variance. RESULTS Among 6,636 included infants, 44.2% (n = 2,935) were late preterm, 26.2% (n = 1,737) early term, and 29.6% (n = 1,964) term. Term infants were more likely to require resuscitation at birth and had lower Apgar scores than late preterm and early term infants (p < 0.001). Length of stay and need for respiratory support decreased with increasing gestational age; however, the proportion of hospital days that intensive care was required increased. CONCLUSION The greatest impact of late preterm infants is on NICU bed occupancy, whereas for term infants it is on intensity of care. Early term infants experience greater rates of some complications than term, demonstrating that risk persists for these infants. These findings have important implications for NICU resource planning and practice.

The influence of refugee status and secondary migration on preterm birth

Background It is unknown whether the risk of preterm birth (PTB) is elevated for forced (refugee) international migrants and whether prolonged displacement amplifies risk. While voluntary migrants who arrive from a country other than their country of birth (ie, secondary migrants) have favourable birth outcomes compared with those who migrated directly from their country of birth (ie, primary migrants), secondary migration may be detrimental for refugees who experience distinct challenges in transition countries. Our objectives were (1) to determine whether refugee status was associated with PTB and (2) whether the relation between refugee status and PTB differed between secondary and primary migrants. Methods We conducted a retrospective population-based cohort study. Ontario immigration (2002–2010) and hospitalisation data (2002–2010) were linked to estimate adjusted cumulative odds ratios (ACOR) of PTB (22–31, 32–36, 37–41 weeks of gestation), with 95% CIs (95% CI) comparing refugees with non-refugees. We further included a product term between refugee status and secondary migration. Results Overall, refugees (N=12 913) had 17% greater cumulative odds of short gestation (ACOR=1.17, 95% CI 1.07 to 1.28) compared with non-refugees (N=110 640). Secondary migration modified the association between refugee status and PTB (p=0.007). Secondary refugees had 58% greater cumulative odds of short gestation (ACOR=1.58, 95% CI 1.25 to 2.00) than secondary non-refugees, while primary refugees had 12% greater cumulative odds of short gestation (ACOR=1.12, 95% CI 1.02 to 1.23) than primary non-refugee immigrants. Conclusions Refugee status, jointly with secondary migration, influences PTB among migrants.

How often are late preterm births the result of non-evidence based practices: analysis from a retrospective cohort study at two tertiary referral centres in a nationalised healthcare system

To determine the proportion, characteristics, and predictors of late preterm birth (LPTB) in relation to evidence‐based (EB) and non‐evidence based (NEB) indications.

Spatial variability of gastroschisis in Canada, 2006-2011: An exploratory analysis

OBJECTIVES: Gastroschisis is a serious birth defect of the abdominal wall that is associated with mortality and significant morbidity. Our understanding of the factors causing this defect is limited. The objective of this paper is to describe the geographic variation in incidence of gastroschisis and characterize the spatial pattern of all gastroschisis cases in Canada between 2006 and 2011. Specifically, we aimed to ascertain the differences in spatial patterns between geographic regions and identify significant clusters and their location.METHODS: The study population included 641 gastroschisis cases from the Canadian Pediatric Surgery Network (CAPSNet) database, a population-based dataset of all gastroschisis cases in Canada. Cases were geocoded based on maternal residence. Using Statistics Canada live-birth data as a denominator, the total prevalence of gastroschisis was calculated at the provincial/territorial levels. Random effects logistic models were used to estimate the rates of gastroschisis in each census division. These rates were then mapped using ArcGIS. Cluster detection was performed using Local Indicators of Spatial Association (LISA).RESULTS: There is significant spatial heterogeneity of the rate of gastroschisis across Canada at both the provincial/territorial and census-division level. The Yukon, Northwest Territories and Prince Edward Island have higher overall rates of gastroschisis relative to other provinces/territories. Several census divisions in Alberta, Manitoba, Saskatchewan, Ontario, Northwest Territories and British Columbia demonstrated case “clusters”, i.e., focally higher rates in discrete areas relative to surrounding areas.CONCLUSIONS: There is clear evidence of spatial variation in the rates of gastroschisis across Canada. Future research should explore the role of area-based variables in these patterns to improve our understanding of the etiology of gastroschisis.RésuméOBJECTIFS: Le laparoschisis est une anomalie congénitale grave de la paroi abdominale associée à la mortalité et à une importante morbidité. Nos connaissances des facteurs à l’origine de cette malformation sont limitées. Nous avons cherché à décrire la variation spatiale de l’incidence du laparoschisis et à caractériser la structure spatiale de tous les cas de laparoschisis survenus au Canada entre 2006 et 2011. Plus précisément, nous avons voulu vérifier les différentes structures spatiales des régions géographiques et repérer les grappes significatives et leur emplacement.MÉTHODE: La population étudiée comptait 641 cas de laparoschisis trouvés dans la base de données du Réseau canadien de chirurgie pédiatrique (CAPSNet), un fichier de données populationnelles de tous les cas de laparoschisis au Canada. Les cas ont été géocodés d’après le lieu de résidence de la mère. En utilisant les données de Statistique Canada sur les naissances vivantes comme dénominateur, nous avons calculé la prévalence totale du laparoschisis par province ou territoire et par secteur du recensement. Ces taux ont ensuite été cartographiés à l’aide d’ArcGIS. La détection des concentrations de cas a été effectuée à l’aide d’indicateurs locaux d’associations spatiales.RÉSULTATS: Il existe une hétérogénéité spatiale importante des taux de laparoschisis au Canada, tant à l’échelle provinciale et territoriale qu’à celle des secteurs du recensement. Le Yukon, les Territoires du Nord-Ouest et l’Île-du-Prince-Édouard ont des taux globaux de laparoschisis plus élevés que les autres provinces et territoires. Plusieurs secteurs du recensement en Alberta, au Manitoba, en Saskatchewan, en Ontario, dans les Territoires du Nord-Ouest et en Colombie-Britannique présentent des grappes de laparoschisis, contrairement à leurs contreparties.CONCLUSIONS: Il existe des preuves manifestes de variation spatiale des taux de laparoschisis au Canada. Les recherches futures devraient explorer le rôle des variables régionales dans cette configuration, afin d’améliorer nos connaissances de l’étiologie du laparoschisis.

Relationship of mode of conception and sex concordance with mortality/morbidity in preterm twins

OBJECTIVE To assess the association of mode of conception and sex concordance with neonatal outcomes in very preterm twins. STUDY DESIGN Twin pairs born at gestational age ≤ 32 weeks and admitted to a Level 3 neonatal intensive care unit (NICU) in 2010-2011 were retrospectively identified from the Canadian Neonatal Network™ database. A composite outcome representing neonatal mortality or any severe morbidity (intraventricular hemorrhage grades ≥ 3 or periventricular leukomalacia, retinopathy of prematurity stages ≥ 3, bronchopulmonary dysplasia, or necrotizing enterocolitis stages ≥ 2) was compared between twins conceived using assisted reproduction technologies (ARTs) or spontaneously (SP), and tested for association with sex concordance in individual-level and pair-wise multivariable logistic regression analyses. RESULTS Study subjects included 1,508 twins from 216 ART (53 [25%] male-male, 104 [48%] male-female, and 59 [27%] female-female) and 538 SP (192 [36%] male-male, 123 [23%] male-female, and 223 [41%] female-female) pairs. No statistically significant association was detected between mode of conception and the composite outcome of mortality/morbidities. The composite outcome was significantly higher in same-sex than in opposite-sex twins (OR = 1.68; 95% CI = [1.09, 2.59]). This relationship was most pronounced in ART pairs (OR = 2.25; 95% CI = [1.02, 4.98]), with increased rates in one or both twins from male-male versus opposite-sex ART pairs (OR = 3.0; 95% CI = [1.07, 8.36]). CONCLUSION Same-sex pairing was associated with higher mortality/morbidities in very preterm twins admitted to the NICU, and can be used in clinical practice to identify twins at higher risk of adverse neonatal outcomes.

Late preterm birth and previous cesarean section: a population-based cohort study

Abstract Background: Late preterm birth (LPB) is increasingly common and associated with higher morbidity and mortality than term birth. Yet, little is known about the influence of previous cesarean section (PCS) and the occurrence of LPB in subsequent pregnancies. We aim to evaluate this association along with the potential mediation by cesarean sections in the current pregnancy. Methods: We use population-based birth registry data (2005–2012) to establish a cohort of live born singleton infants born between 34 and 41 gestational weeks to multiparous mothers. PCS was the primary exposure, LPB (34–36 weeks) was the primary outcome, and an unplanned or emergency cesarean section in the current pregnancy was the potential mediator. Associations were quantified using propensity weighted multivariable Poisson regression, and mediating associations were explored using the Baron-Kenny approach. Results: The cohort included 481,531 births, 21,893 (4.5%) were LPB, and 119,983 (24.9%) were predated by at least one PCS. Among mothers with at least one PCS, 6307 (5.26%) were LPB. There was increased risk of LPB among women with at least one PCS (adjusted Relative Risk (aRR): 1.20 (95%CI [1.16, 1.23]). Unplanned or emergency cesarean section in the current pregnancy was identified as a strong mediator to this relationship (mediation ratio = 97%). Conclusions: PCS was associated with higher risk of LPB in subsequent pregnancies. This may be due to an increased risk of subsequent unplanned or emergency preterm cesarean sections. Efforts to minimize index cesarean sections may reduce the risk of LPB in subsequent pregnancies.

Association between congenital anomalies and area-level deprivation among infants in neonatal intensive care units.

OBJECTIVE To examine the relationship between area-level material deprivation and the risk of congenital anomalies in infants admitted to neonatal intensive care units (NICUs) across Canada. STUDY DESIGN The Canadian Neonatal Network database was used to identify admitted infants who had congenital anomalies between 2005 and 2009. The association between congenital anomalies and material deprivation quintile was assessed using logistic regression analysis. RESULTS Of 55,961 infants admitted to participating NICUs during the study period, 6002 (10.7%) had major, 6244 (11.2%) had minor, and 43,715 (78.1%) had no anomalies. There were higher odds of major anomalies (odds ratio [OR] 1.13, 95% confidence interval [CI] 1.03 to 1.24) but not minor anomalies (OR 1.01, 95% CI 0.93 to 1.11) in the highest-deprivation areas as compared with the lowest-deprivation area of maternal residence. Analyses of groups of major anomalies revealed higher odds for chromosomal (OR 1.48, 95% CI 1.05 to 2.10) and multiple-systems (OR 1.40, 95% CI 1.14 to 1.71) anomalies in the highest-deprivation areas compared with the lowest-deprivation areas. CONCLUSION There are socioeconomic inequalities in the risk of major congenital anomalies, especially chromosomal and multiple-systems anomalies, in the NICU population with the highest rates in the most socioeconomically deprived areas.

Cold-related injuries in a cohort of homeless adults

ABSTRACT People experiencing homelessness have an increased risk of cold-related injuries. This study determined the rate of emergency department (ED) visits for cold-related injuries among homeless adults and low-income controls in Toronto, Canada. Homeless individuals were recruited at shelters and meal programs. Age- and sex-matched controls living in low-income neighborhoods were selected. ED utilization was ascertained over 4-years of follow-up (2005–9) using administrative databases. A total of 16 ED visits for cold-related injuries were observed among 587 homeless men and 296 homeless women. The rate of ED visits was 6.7 (95% CI, 4.2–12.4) per 1000 person-years of observation among homeless men and 0.9 (95% CI, 0.03–5.6) among homeless women. ED visit rates were significantly higher among homeless men compared to low-income men (P < 0.001) and significantly higher among homeless men compared to homeless women (P = 0.03). Targeted public health interventions are needed to reduce the risk of cold-related injuries among people experiencing homelessness.