Birth and postnatal outcomes among infants of immigrant parents of different admission categories and parents born in Canada: a population-based retrospective study.

BACKGROUND: Most studies of disparities in birth and postnatal outcomes by parental birthplace combine all immigrants into a single group. We sought to evaluate heterogeneity among immigrants in Canada by comparing birth and postnatal outcomes across different immigration categories. METHODS: We conducted a population-based retrospective study using Statistics Canada data on live births and stillbirths (1993-2017) and infant deaths (1993-2018), linked to parental immigration data (1960-2017). We classified birthing parents as born in Canada, economic-class immigrants, family-class immigrants, or refugees, and evaluated differences in preterm births, small-for-gestational-age (SGA) and large-for-gestational-age (LGA) births, stillbirths, and infant deaths among singleton births by group. RESULTS: Among 7 980 650 births, 1 715 050 (21.5%) were to immigrants, including 632 760 (36.9%) in the economic class, 853 540 (49.8%) in the family class, and 228 740 (13.4%) refugees. Compared with infants of Canadian-born birthing parents, infants of each of the 3 immigrant groups had higher risk of preterm birth, SGA birth, and stillbirth, but lower risk of LGA birth and neonatal death. Compared with infants of economic-class immigrants, infants of refugees had higher risk of early preterm birth (0.9% v. 0.8%, adjusted risk ratio [RR] 1.08, 95% confidence interval [CI] 1.01-1.15) and LGA birth (9.2% v. 7.5%, adjusted RR 1.12, 95% CI 1.10-1.15), but lower risk of SGA birth (10.2% v. 11.0%, adjusted RR 0.92, 95% CI 0.90-0.94), while infants of family-class immigrants had higher risk of SGA birth (12.2% v. 11.0%, adjusted RR 1.01, 95% CI 1.00-1.02). Risk of stillbirth, neonatal death, and overall infant death did not differ significantly among immigrant groups. INTERPRETATION: Heterogeneity exists in outcomes of infants born to immigrants to Canada across immigration categories. These results highlight the importance of disaggregating immigrant populations in studies of health disparities.

Work precarity, employment characteristics and health among Canada's long-term care and seniors' home workers during the COVID-19 pandemic.

Background: The COVID-19 pandemic has highlighted several issues among health care workers in Canada's long-term care and seniors' (LTCS) homes, including labour shortages, staff retention difficulties, overcrowding, and precarious working conditions. There is currently a lack of information on the health, well-being and working conditions of health care workers in LTCS homes - many of them immigrants - and a limited understanding of the relationship between them. This paper examines differences between immigrant and non-immigrant workers' health outcomes and precarious working conditions during the pandemic. Data and methods: The data were from the 2021 Survey on Health Care Workers' Experiences During the Pandemic, which collected information on LTCS home health care workers' (n=2,051) health, employment or work experiences, and working environment during the COVID-19 pandemic. Summary statistics and multivariable logistic regressions were conducted to examine the association between precarious work and workers' health (life stress, mental health and general health), stratified by immigrant status. Selected working characteristics were included in the regression models as covariates, namely occupation, number of locations worked, facility ownership status and number of years worked. Results: Immigrant health care workers were more likely than non-immigrant health care workers to experience precarious work in LTCS homes. Precarious work - characterized by income loss, reduced hours of work, and unpaid leave - was associated with stress and poor general health among immigrant and non-immigrant workers in the sector. Employment precarity was also associated with poor mental health for immigrant workers, but there was no association for non-immigrant workers. Interpretation: Employment precarity and the health and well-being of health care workers warrants further attention, in particular among immigrants employed in the LTCS residential care sector.

Sex differences in COVID-19 deaths in the early months of the pandemic in Canada: An examination with an immigration lens.

Background: At the onset of the COVID-19 pandemic, there was an overrepresentation of males in COVID-19 deaths worldwide, with Canada reporting more female COVID-19 deaths. This paper examines the overrepresentation of female COVID-19 deaths in Canada, with an immigration lens. Data and methods: Data were extracted from the COVID-19 Sex-Disaggregated Data Tracker to compare the sex distribution of COVID-19 deaths in Canada with that of other countries. A linkage of deaths to the Longitudinal Immigration Database (IMDB) allows for the comparison of sex-specific COVID-19 death rates by immigrant status for age and geography, as well as by major employment sector among immigrants, using the tax data from the IMDB. Results: While there were proportionately more female than male COVID-19 deaths in Canada in the early months of the pandemic, this trend was mainly a phenomenon among non-immigrants aged 85 and older. In addition, COVID-19-specific death rates for males were higher than those for females across age groups by immigrant status, except for those aged 85 and older among the non-immigrant population. Among immigrants, the death rate among health care and social assistance workers was higher among males than among females (10.7 vs. 2.9 per 100,000 population). The initially observed overrepresentation of female COVID-19 deaths to male COVID-19 deaths in Canada evened out in the summer of 2021. Interpretation: The higher proportion of female COVID-19 deaths was likely related to the high concentration of COVID-19 deaths in long-term care facilities, where a lower institutionalization rate for immigrants had been observed. Since the implementation of vaccination targeting long-term care facility residents in Canada, the overrepresentation of female COVID-19 deaths ceased.

The impacts of COVID-19 on immigrants and the healthy immigrant effect: Reflections from Canada.

Discussions about potential long-term health consequences of the COVID-19 pandemic on immigrant health and the healthy immigrant effect (HIE) remain unaddressed. Drawing on Canada as a case study, we summarize the primary and secondary impacts of COVID-19 on immigrants. We find that recent and female immigrants as well refugees have fared far worse than either their more established and male counterparts or the Canadian-born population. We then discuss how COVID-19 might influence (or weaken) immigrants' previously documented health advantage. We highlight two structural conditions induced by the pandemic that may alter the health profile of immigrants; namely, immigration policy and delayed medical treatments. Reflections on the requisite data for monitoring and tracking the overall impact of COVID-19 on immigrants' health are included. Finally, we conclude with a discussion of the Canadian patterns and its potential relevance to immigrants and the HIE in the United States.

Mental health and neurocognitive disorder-related hospitalization rates in immigrants and Canadian-born population: a linkage study.

OBJECTIVES: Mental health and neurocognitive conditions are important causes of hospitalization among immigrants, though patterns may vary by immigrant category, world region of origin, and time since arrival in Canada. This study uses linked administrative data to explore differences in mental health hospitalization rates between immigrants and individuals born in Canada. METHODS: Hospital records from the Discharge Abstract Database and the Ontario Mental Health Reporting System for 2011 to 2017 were linked to the 2016 Longitudinal Immigrant Database and to Statistics Canada's 2011 Canadian Census Health and Environment Cohort. Age-standardized hospitalization rates for mental health-related conditions (ASHR-MHs) were derived for immigrants and the Canadian-born population. ASHR-MHs overall and for leading mental health conditions were compared between immigrants and the Canadian-born population, stratified by sex and selected immigration characteristics. Quebec hospitalization data were not available. RESULTS: Overall, immigrants had lower ASHR-MHs compared to the Canadian-born population. Mood disorders were leading causes of mental health hospitalization for both cohorts. Psychotic, substance-related, and neurocognitive disorders were also leading causes of mental health hospitalization, although there was variation in their relative importance between subgroups. Among immigrants, ASHR-MHs were higher among refugees and lower among economic immigrants, those from East Asia, and those who arrived in Canada most recently. CONCLUSION: Differences in hospitalization rates among immigrants from various immigration streams and world regions, particularly for specific types of mental health conditions, highlight the importance of future research that incorporates both inpatient and outpatient mental health services to further understand these relationships.

RéSUMé: OBJECTIFS: Les problèmes de santé mentale et les troubles neurocognitifs sont des causes importantes d'hospitalisation chez les immigrants, bien que les tendances puissent varier selon la catégorie d'immigrants, la région d'origine mondiale et le temps écoulé depuis l'arrivée au Canada. Cette étude utilise des données administratives couplées afin d'explorer les différences dans les taux d'hospitalisation en santé mentale entre les immigrants et les personnes nées au Canada. MéTHODES: Les dossiers hospitaliers de la Base de données sur les congés des patients et du Système d'information ontarien sur la santé mentale de 2011 à 2017 ont été couplés à la Base de données longitudinales sur l'immigration de 2016 et aux cohortes santé et environnement du Recensement canadien de 2011 de Statistique Canada. Les taux d'hospitalisation normalisés selon l'âge pour les problèmes de santé mentale (THNA-SM) ont été comparés entre les immigrants et la population née au Canada, stratifiés selon le sexe et certaines caractéristiques d'immigration. Les données sur les hospitalisations au Québec n'étaient pas disponibles. RéSULTATS: Dans l'ensemble, les immigrants avaient des THNA-SM plus faibles que la population née au Canada. Les troubles de l'humeur étaient les principales causes d'hospitalisation en santé mentale pour les deux cohortes. Les troubles psychotiques, liés aux substances et neurocognitifs étaient également les principales causes d'hospitalisation en santé mentale, bien que leur importance relative varie entre les sous-groupes. Chez les immigrants, les THNA-SM étaient plus élevés chez les réfugiés et plus faibles chez les immigrants économiques, ceux de l'Asie de l'Est et ceux qui sont arrivés au Canada plus récemment. CONCLUSION: Les différences dans les taux d'hospitalisation chez les immigrants des divers groupes d'immigration et régions du monde, plus particulièrement pour certains types de problèmes de santé mentale, soulignent l'importance de recherches futures qui intègrent les services de santé mentale aux patients hospitalisés ainsi qu'aux patients externes afin de mieux comprendre ces relations.

Urban heat island effect-related mortality under extreme heat and non-extreme heat scenarios: A 2010-2019 case study in Hong Kong.

The urban heat island (UHI) effect exacerbates the adverse impact of heat on human health. However, while the UHI effect is further intensified during extreme heat events, prior studies have rarely mapped the UHI effect during extreme heat events to assess its direct temperature impact on mortality. This study examined the UHI effect during extreme heat and non-extreme heat scenarios and compared their temperature-mortality associations in Hong Kong from 2010 to 2019. Four urban heat island degree hour (UHIdh) scenarios were mapped onto Hong Kong's tertiary planning units and classified into three levels (Low, Moderate, and High). We assessed the association between temperature and non-external mortality of populations living in each UHIdh level for the extreme heat/non-extreme heat scenarios during the 2010-2019 hot seasons. Our results showed substantial differences between the temperature-mortality associations in the three levels under the UHIdh extreme heat scenario (UHIdh_EH). While there was no evidence of increased mortality in Low UHIdh_EH areas, the mortality risk in Moderate and High UHIdh_EH areas were significantly increased during periods of hot temperature, with the High UHIdh_EH areas displaying almost double the risk (RR: 1.08, 95%CI: 1.03, 1.14 vs. RR: 1.05, 95 % CI: 1.01, 1.09). However, other non-extreme heat UHI scenarios did not demonstrate as prominent of a difference. When stratified by age, the heat effects were found in Moderate and High UHIdh_EH among the elderly aged 75 and above. Our study found a difference in the temperature-mortality associations based on UHI intensity and potential heat vulnerability of populations during extreme heat events. Preventive measures should be taken to mitigate heat especially in urban areas with high UHI intensity during extreme heat events, with particular attention and support for those prone to heat vulnerability, such as the elderly and poorer populations.

Modeling spatiotemporal carbon emissions for two mega-urban regions in China using urban form and panel data analysis.

Spatiotemporal monitoring of urban CO2 emissions is crucial for developing strategies and actions to mitigate climate change. However, most spatiotemporal inventories do not adopt urban form data and have a coarse resolution of over 1 km, which limits their implications in intra-city planning. This study aims to model the spatiotemporal carbon emissions of the two largest mega-urban regions in China, the Yangtze River Delta and the Pearl River Delta, using urban form data from the Local Climate Zone scheme and landscape metrics, nighttime light images, and a year-fixed effects model at a fine resolution from 2012 to 2016. The panel data model has an R2 value of 0.98. This study identifies an overall fall in carbon emissions in both regions since 2012 and a slight elevation of emissions from 2015 to 2016. In addition, urban compaction and integrated natural landscapes are found to be related to low emissions, whereas scattered low-rise buildings are associated with rising carbon emissions. Furthermore, this study more accurately extracts urban areas and can more clearly identify intra-urban variations in carbon emissions than other datasets. The open data supported methodology, regression models, and results can provide accurate and quantifiable evidence at the community level for achieving a carbon-neutral built environment.

Hospitalization related to chronic hepatitis B and C in recent immigrants in Canada: An immigration administrative data-linked, population-based cohort study.

Background: Canadian immigrants from countries where the hepatitis B virus (HBV) and hepatitis C virus (HCV) are endemic may be at higher risk of liver-related disease than Canadian-born residents. This study compared HBV- and HCV-related hospitalizations in Canadian immigrants (arriving from 1980 to 2013) and long-term residents (Canadian-born population and pre-1980 immigrants) and aimed to describe the burden of disease in both groups. Methods: Based on the 2004/2005-to-2013/2014 hospital Discharge Abstract Database linked to the 1980-to-2013 Longitudinal Immigration Database, this descriptive cross-sectional study examined the distribution of HBV- and HCV-related hospitalizations, lengths of stay, comorbidities, and sequelae incurred by immigrants and long-term residents in Canada. With a linkage rate of 85%, 5,854,949 immigrants were included in the study. Proportions of HBV- and HCV-related hospitalizations attributable to immigrants were calculated. Results: By birth country risk level, 22% of HBV-related hospital events among recent immigrants, and 20% of those related to HCV, were among people from high-risk countries. Proportionally, fewer immigrants had comorbidities than long-term residents. The top two hospital-related sequelae in both groups were cirrhosis and ascites, and liver cancer. While immigrants made up 16% of the Canadian population, they incurred 37% of HBV-related hospitalizations and 9% of HCV-related hospitalizations, giving ratios of hepatitis-related hospitalizations relative to the population share of 2.3 (95% confidence interval [CI]: 2.2 to 2.5) and 0.5 (95% CI: 0.5 to 0.6) respectively. These ratios were higher among seniors, at 4.4 (95% CI: 3.9 to 4.9) and 2.3 (95% CI: 1.9 to 2.6), respectively. Interpretation: Immigrants can require hospitalization for hepatitis in Canada, especially for HBV. These results may inform health screening for HBV or HCV in the Canadian immigration context.

Integrating weather observations and local-climate-zone-based landscape patterns for regional hourly air temperature mapping using machine learning.

Air temperature is a crucial variable of urban meteorology and is essential to many urban environments, urban climate and climate-change-related studies. However, due to the limited observational records of air temperature and the complex urban morphology and environment, it might not be easy to map the hourly air temperature with a fine resolution at the surface level within and around cities via conventional methods. Thus, this study employed machine learning (ML) algorithms and meteorological and landscape data to develop hourly air temperature mapping techniques and methods at the 1-km resolution over a multi-year warm seasons period. Guangdong Province, China was selected for the case study. Random forest algorithm was employed for the hourly air temperature mapping. The validation results showed that the hourly air temperature maps exhibit good accuracy from 2008 to 2019, with mean R2, root mean square error (RMSE) and mean absolute error (MAE) values of 0.8001, 1.4821 °C and 1.0872 °C, respectively. The importance assessment of the driving factors showed that meteorological factors, especially relative humidity, contributed the most to the air temperature mapping. Simultaneously, landscape factors also played a non-negligible role. Further analysis revealed that the maps steadily maintained high accuracy at nighttime (20:00-7:00), which is essential for investigating nighttime urban climate conditions, especially the urban heat island effect. Moreover, a correlation existed between the nighttime air temperature changes and urban morphology represented by the local climate zones. Air temperatures tended to fall more slowly in the core of metropolitan areas than in the urban fringe. Using ML, this study reliably improves the spatial refinement of hourly air temperature mapping and reveals the spatially explicit air temperature patterns in and around cities at different times in a day during the warm seasons. Moreover, it provides a novel valuable and reliable dataset for air-temperature-related implementation and studies.

Towards decarbonisation targets by changing setpoint temperature to avoid building overcooling and implementing district cooling in (sub)tropical high-density cities - A case study of Hong Kong.

Climate warming, rapid economic development, and urbanisation in (sub)tropical regions lead to increasing electricity demand for building air-conditioning that could jeopardise the efforts of decarbonisation required to meet the climate change mitigation goals. This study investigates two strategies to reduce building energy consumption due to air-conditioning: 1) the bottom-up adoption of an Adaptive Thermal Comfort (ATC)-based cooling setpoint temperature and 2) the top-down implementation of efficient District Cooling Systems (DCS). The subtropical high-density city of Hong Kong is chosen for case study since detailed data on the city's current and realistic future urban form and function are available. Numerical simulations representing the feedback between urban climate and building energy consumption are conducted by employing a mesoscale atmospheric model coupled to an urban climate and building energy model for a scenario of future (mid-21st century) Hong Kong. A prolonged high temperature event representative of future extreme conditions is simulated, during which the ATC and DCS strategies reduce building cooling energy consumption by 9.7% and 5.9%, respectively. The ATC has almost no effect on the local meteorological conditions, whereas the DCS reduces daytime sensible heat flux by up to 600 W/m2 and near-surface air temperature by almost 1 °C in the districts where it is adopted. The DCS thus also contributes to lowering outdoor heat stress in these areas. The cost-free ATC strategy is easily applicable in residential buildings worldwide and can break the vicious cycle in overcooled buildings, where occupants are acclimatised to lower indoor temperature and thus require more air-conditioning than necessary. Apart from reducing energy consumption and near-surface air temperature, the DCS brings additional benefits in building space utilisation and rooftop design. Future policy orientations should therefore encourage a societal change towards the ATC lifestyle and incorporate DCS in the planning of new development areas.

All-cause acute care hospitalization rates of immigrants and the Canadian-born population: A linkage study.

BACKGROUND: As Canadian immigration levels increase, knowledge concerning immigrant health becomes increasingly important for health system policy and planning. This study compares the rate of all-cause hospitalization among immigrants with that of their Canadian-born counterparts. DATA AND METHODS: Using records from the Discharge Abstract Database (2004/2005 to 2016/2017) and the Ontario Mental Health Reporting System (2006/2007 to 2017/2018) linked to the 2016 Longitudinal Immigration Database, this study compared the age-standardized hospitalization rates (ASHRs) among immigrants with those of the Canadian-born population; the latter were obtained from a linkage based on the 2011 National Household Survey. Comparisons were made at the International Classification of Diseases chapter level by immigrant landing year, admission category and world region of birth. Quebec data were not available. RESULTS: Overall, ASHRs among immigrants were lower than for the Canadian-born population. Immigrants in the economic class had the lowest ASHR, followed by those in the family class and among refugees. After pregnancy was excluded, leading hospitalization causes were similar for immigrants and the Canadian-born population, where top causes included digestive system and circulatory diseases, injuries, and cancer. In male and female immigrants, the ASHRs were lowest among those from East Asia. By landing year, males arriving earlier had the highest ASHR compared with the most recent arrivals. When pregnancy was excluded and while the differential in ASHRs among females by landing year remained, the magnitude was smaller. INTERPRETATION: These results corroborate those from previous studies suggesting a healthy immigrant effect, but also reveal heterogeneity in ASHRs within the immigrant population. They provide a baseline for comparison of health status between populations, which enables further monitoring and informs health-system policy and planning.

Access to mental health consultations by immigrants and refugees in Canada.

BACKGROUND: Few quantitative studies have used national-level data to examine access to mental health consultation (MHC) by immigrants in Canada, and even fewer studies investigate MHCs using the following variables: immigrant admission category, duration in Canada since landing and world source regions. This study examines MHCs by immigrants and refugees-compared with those of Canadian-born respondents-while controlling for self-reported mental health (SRMH) and immigrant characteristics, using a population-based survey linked to immigrant landing information. This study, which is based on a linked database, allows for much richer insight into immigrant populations than most previous studies. DATA AND METHODS: Based on data from four cycles (2011 to 2014) of the Canadian Community Health Survey linked to data from the Longitudinal Immigration Database, the odds ratios of having had MHCs are compared between the Canadian-born population and immigrants by immigration dimensions, while controlling for SRMH. Results are hierarchically adjusted for age, sex, socioeconomic factors and sense of belonging. RESULTS: After the above-mentioned factors were controlled for, immigrants were much less likely than Canadian-born respondents to access MHCs. Specifically, compared with the Canadian-born population that had high levels of SRMH, immigrants with high levels of SRMH were statistically less likely to have had an MHC (odds ratio [OR]=0.5, 95% confidence interval [CI] from 0.4 to 0.5), while those with low SRMH levels were more likely to report an MHC (OR=4.8, 95% CI from 4.5 to 5.1, for the Canadian-born population but OR=1.8, 95% CI from 1.5 to 2.1, for immigrants). Most Asian immigrants with low SRMH levels were only as likely to report MHCs as Canadian-born respondents with high SRMH levels. Refugees with low SRMH levels also had only a slightly elevated MHC level (OR=1.6, 95% CI from 1.1 to 2.3) compared with Canadian-born individuals with high SRMH levels. Overall, refugees were not more likely than immigrants of other admission categories to report having had an MHC, even though previous findings have shown that refugees report low levels of SRMH. DISCUSSION: This study provides new evidence on the differences in access to MHC between Canadian-born individuals and immigrants by various characteristics, while controlling for SRMH. Results probably reflect the structural or cultural barriers to MHC and point to a possible pathway to either maintain or improve mental health among immigrants.

Thermal-irradiant performance of green infrastructure typologies: Field measurement study in a subtropical climate city.

Greenery infrastructure (GI) is an important design strategy for sustainable cities and communities' development, as it brings multiple benefits including mitigating urban heat island. Based on the implementation locations, three typical GI typologies, namely green roof, green wall, and ground tree, are widely adopted in urban communities. As previous studies focused on one single GI and mainly studied their thermal features, this study aims to fill the gap by investigating three GI typologies within one site; their thermal-irradiant performance was compared for four typical summer days in a subtropical city. Firstly, stationary and transect measurements were taken for six points (three greenery and three bare points); two typical measuring methods, i.e., the globe thermometer and the six-directional methods, were employed to collect irradiant variables. Secondly, the thermal-irradiant differences were revealed among GI typologies and temporal periods; two measuring methods were compared for their capabilities in detecting the irradiant variations near three GI typologies. Results showed that: 1) the ground tree experienced the smallest thermal-irradiant average and variation among three GI typologies; 2) the morning session (09:00-12:00) had the largest thermal-irradiant reduction and variations for three GI typologies; and 3) the six-directional method showed higher sensitivity towards the irradiant variations near three GI typologies; the globe thermometer method is not suitable for tree-shaded areas. This study provides a comprehensive understanding of proper selection of MRT measuring methods and GI implementation for thermal comfort, especially for the subtropical cities. Practically, this study shows designers and policymakers on how to implement GI typologies for climate-resilient design.

A Multiscale Land Use Regression Approach for Estimating Intraurban Spatial Variability of PM2.5 Concentration by Integrating Multisource Datasets.

Poor air quality has been a major urban environmental issue in large high-density cities all over the world, and particularly in Asia, where the multiscale complex of pollution dispersal creates a high-level spatial variability of exposure level. Investigating such multiscale complexity and fine-scale spatial variability is challenging. In this study, we aim to tackle the challenge by focusing on PM2.5 (particulate matter with an aerodynamic diameter less than 2.5 µm,) which is one of the most concerning air pollutants. We use the widely adopted land use regression (LUR) modeling technique as the fundamental method to integrate air quality data, satellite data, meteorological data, and spatial data from multiple sources. Unlike most LUR and Aerosol Optical Depth (AOD)-PM2.5 studies, the modeling process was conducted independently at city and neighborhood scales. Correspondingly, predictor variables at the two scales were treated separately. At the city scale, the model developed in the present study obtains better prediction performance in the AOD-PM2.5 relationship when compared with previous studies (R2¯ from 0.72 to 0.80). At the neighborhood scale, point-based building morphological indices and road network centrality metrics were found to be fit-for-purpose indicators of PM2.5 spatial estimation. The resultant PM2.5 map was produced by combining the models from the two scales, which offers a geospatial estimation of small-scale intraurban variability.

The mental health of immigrants and refugees: Canadian evidence from a nationally linked database.

BACKGROUND: Few studies of the healthy immigrant effect (HIE) have examined the mental health outcomes of Canadian-born individuals on a national scale compared with immigrants by admission category. This study fills this gap by examining the self-reported mental health (SRMH) of immigrants by admission category and other immigration dimensions (e.g., source world region and duration since landing) and making comparisons with Canadian-born respondents to a population-based survey. DATA AND METHODS: Based on four cycles (2011 to 2014) of the Canadian Community Health Survey (CCHS) linked to the Longitudinal Immigration Database (IMDB), odds ratios of high (i.e., excellent or very good) SRMH among Canadian-born respondents and IMDB-linked immigrants are compared using logistic regression. Among the IMDB immigrant population, high SRMH was also examined according to the above-mentioned immigration dimensions. Adjusted results were hierarchically controlled for age, sex, social and economic factors, and sense of belonging. RESULTS: Age-sex adjusted results show that immigrants, especially refugees, are less likely than the Canadian-born population to report high mental health levels, but these differences disappeared after full adjustment. The odds of immigrants having high SRMH differed more by source world region and duration since landing. For example, fully adjusted results show support for the HIE, with recent immigrants (interviewed within 10 years of landing) more likely to report high SRMH than either the Canadian-born population or established immigrants. Greater odds of high SRMH among recent immigrants also holds across admission classes and for selected world regions. DISCUSSION: This study provides new evidence on differences in mental health between Canadian-born individuals and immigrants by various characteristics. Results support a deterioration of the HIE in SRMH and identify factors significantly associated with SRMH. This study can also serve as a baseline for further studies on the impact of COVID-19 on immigrants' mental health by immigrant category.

Right tree, right place (urban canyon): Tree species selection approach for optimum urban heat mitigation - development and evaluation.

The re-integration of trees into the urban landscape is a veritable strategy for urban climate mitigation and adaptation. However, dysfunctional trees in terms of urban heat mitigation are dominant in many sub-tropical cities' landscapes due to the lack of scientific basis of tree selection. Therefore, this study proposes and evaluates a methodological framework as an approach for "right tree, right place" for urban heat mitigation through parametric ENVI-met simulations that involve the combination of 54 generic tree forms and 10 characteristic urban morphology - Sky-View Factor (SVF). Results show variable temperature regulation by tree forms (species) with varying magnitude in different urban morphology. Daytime and nighttime temperature regulation effects were between 0.3 °C - 1.0 °C and 0.0 °C - 2.0 °C, respectively depending on tree forms and SVF value. Furthermore, the Heat Reduction Potential (HRP) of trees forms were determined in terms of their human thermal comfort improvement. In general, we found a range of +5% and - 20% depending on SVF, negative and positive values imply heat reduction and increment, respectively. With the competing shading effect of buildings, the HRP of trees reduces from high to low SVF area with variable magnitude among tree forms (species). Hence, the proposed morphology-based tree selection approach was evaluated by comparison with two uninformed selection approaches in a realistic urban neighborhood in Hong Kong. Results clearly indicate the proposed approach's capability in improving human thermal comfort by up two times more than either of the other approaches. Finally, evidence-based recommendations were given for the reference of policy-makers when they make urban green development plan.

Assessment of Local Climate Zone Classification Maps of Cities in China and Feasible Refinements.

Local climate zone (LCZ) maps that describe the urban surface structure and cover with consistency and comparability across cities are gaining applications in studies of urban heat waves, sustainable urbanization and urban energy balance. Following the standard World Urban Database and Access Portal Tools (WUDAPT) method, we generated LCZ maps for over 20 individual cities and 3 major economic regions in China. Based on the confusion matrices constructed by manual comparison between the predicted classes and ground truths, we highlight the following: (1) notable variation in overall accuracies (i.e., 60%-89%) among cities were observed, which was mainly due to class incompleteness and distinct proportions of natural landscapes; (2) building classes in selected cities were poorly classified in general, with a mean accuracy of 48%; (3) the sparsely built class (i.e., LCZ 9), which is rare in the selected Chinese cities, had the lowest classification accuracy (32% on average), and the class of low plants had the widest accuracy range. The findings indicate that the standard WUDAPT method alone is insufficient for generating LCZ products that demonstrate practical value, especially for built-up areas in China, and the misclassification is largely caused by the lack of building height data. This result is confirmed by a refinement test, in which the urban DEM retrieved from Sentinel-1 data with radar interferometry technique was used. The study shows a detailed and comprehensive assessment of applying the WUDAPT method in China and a feasible refinement strategy to improve the classification accuracy, especially for the built-up types of LCZ. The study could serve as a useful reference for generating quality-ensured LCZ maps. This study also examines and explores the relationship between socio-economic status and LCZ products, which is essential for further implementations.

Designing Urban Green Spaces for Older Adults in Asian Cities.

Elderly populations in Asian countries are expected to increase rapidly in the next few decades. Older adults, particularly in high-density cities, spend a considerable amount of time in urban green spaces (UGSs). The World Health Organization noted that UGSs are key to improving the age-friendliness of neighborhoods. Thus, it is necessary to design UGSs for the promotion of healthy ageing to enhance preventive healthcare and relieve medical burdens. This study conducted interviews using a questionnaire with a sample size of 326 participants in the cities of Hong Kong (China) and Tainan (Taiwan region). The inter-relationships among the design of UGSs (e.g., spatial distribution and accessibility, characteristics of plants and UGSs), older adults' perceptions on safety and aesthetics quality of UGSs, and their self-reported health conditions (assessed by the self-reported SF-12v2 Health Survey) were investigated with bivariate Spearman rank correlation tests. The results indicate that the duration of visits to UGSs was positively associated with mental health and social functioning, two subscales evaluating health-related quality of life in SF 12v2. The statistical model (moderation analysis) showed that such a correlation was especially significant in women and those with low social support and social capital. A positive relationship was found between the physical health subscale and perceived safety in UGSs. This relationship was stronger among older adults living alone (moderation analysis). Furthermore, the color of plants and maintenance condition of UGSs were significant aspects affecting the subjective assessment of aesthetic quality. This study provides useful information regarding how to plan and design urban green spaces with certain characteristics that could improve the accessibility and aesthetic quality, which are preferred by older adults.

The impact of extremely hot weather events on all-cause mortality in a highly urbanized and densely populated subtropical city: A 10-year time-series study (2006-2015).

BACKGROUND: The impact of heatwaves on public health has led to an urgent need to describe extremely hot weather events (EHWEs) and evaluate their health impacts. METHODS: In Hong Kong, a very hot day (VHD) can be defined when the daily maximum temperature ≥ 33 °C, and a hot night (HN) can be identified if the daily minimum temperature ≥ 28 °C. Three lengths of time, nine combinations of VHD and HN, and four categories of occurrence intervals between two EHWEs were considered over 2006-2015. The daily relative risk (RR) of all-cause mortality was estimated using Poisson generalized additive regression models, controlling for both short-term and long-term trends in temperature as well as four air pollutants. Lagged effects of the representative EHWEs were further examined for their association with mortality. Subgroup analysis was conducted for different sex and age groups. RESULTS: Significant associations with raised mortality risks were observed for a single HN, while stronger associations with mortality were observed as significant for five or more consecutive VHDs/HNs. More HNs between the consecutive VHDs also significantly amplified the impact on mortality, with the strongest association observed for EHWEs characterized as 2D3N, and the effect significantly lagged for five days. Therefore, with identifiable health impacts, three thresholds (5VHDs, 5HNs, & 2D3N) were determined to be representative of identical types of EHWEs in Hong Kong. Furthermore, by taking 2 (3) consecutive VHDs (HNs) as one daytime (nighttime) EHWE event, those occurring consecutively without non-hot days (nights) in between were found to be significantly associated with excess mortality risks. Moreover, females and older adults were determined to be relatively more vulnerable to all defined EHWEs. CONCLUSIONS: Among all the observed significant heat-mortality associations in highly urbanized cities, EHWEs that occurred during the nighttime, with extended length, consecutively without any break in between, or in the pattern of 2D3N might require the meteorological administration, healthcare providers, and urban planners to work interactively.

Healthy immigrant effect by immigrant category in Canada.

BACKGROUND: Medical screening plays a role in explaining the healthy immigrant effect (HIE) among immigrants newly landed in Canada. The 2002 Immigration and Refugee Protection Act (IRPA) modernized immigration selection by exempting certain immigrant categories (e.g., refugees and certain family-class immigrants) from inadmissibility on health grounds. This study examines the HIE in the IRPA era by sex, with a focus on those categories affected by the IRPA. DATA AND METHODS: The linked Canadian Community Health Survey (CCHS)-Longitudinal Immigration Database (IMDB) was used to compare sex-specific age-standardized proportions of four health measures between Canadian-born and immigrants aged 20 to 65, overall and by duration since landing. Immigrants who landed within three years of the surveys from 2007 to 2014 were examined by sex and immigrant category. Logistic regression was used to further compare the HIE in the same immigrant sub-groups to the Canadian-born, controlling for age and selected confounders. RESULTS: This study found the HIE in most selected measures for immigrants overall, as well as for those recent immigrants arriving under the IRPA, including the family class. Among refugees, the HIE was observed only in less severe chronic conditions; this was especially the case among females. As expected, a strong HIE was observed among economic-class principal applicants. These health advantages persisted even after adjustment for socioeconomic and health factors. For self-rated health, the advantage existed for some groups only after full adjustment. DISCUSSION: This study is a first look at the healthy immigrant effect under the 2002 Immigration and Refugee Protection Act by immigration category. Results corroborate the existing literature on the presence of the HIE among immigrants: the HIE was found to be much weaker among refugees.