Neighborhood context and infant birthweight among recent immigrant mothers: a multilevel analysis

Prenatal Exposure to Ambient Air Pollution and Cerebral Palsy

Importance

Air pollution is associated with structural brain changes, disruption of neurogenesis, and neurodevelopmental disorders. The association between prenatal exposure to ambient air pollution and risk of cerebral palsy (CP), which is the most common motor disability in childhood, has not been thoroughly investigated.

Objective

To evaluate the associations between prenatal residential exposure to ambient air pollution and risk of CP among children born at term gestation in a population cohort in Ontario, Canada.

Design, Setting, and Participants

Population-based cohort study in Ontario, Canada using linked, province-wide health administrative databases. Participants were singleton full term births (≥37 gestational weeks) born in Ontario hospitals between April 1, 2002, and March 31, 2017. Data were analyzed from January to December 2022.

Exposures

Weekly average concentrations of ambient fine particulate matter with a diameter 2.5 μm (PM2.5) or smaller, nitrogen dioxide (NO2), and ozone (O3) during pregnancy assigned by maternal residence reported at delivery from satellite-based estimates and ground-level monitoring data.

Main outcome and measures

CP cases were ascertained by a single inpatient hospitalization diagnosis or at least 2 outpatient diagnoses for children from birth to age 18 years.

Results

The present study included 1 587 935 mother-child pairs who reached term gestation, among whom 3170 (0.2%) children were diagnosed with CP. The study population had a mean (SD) maternal age of 30.1 (5.6) years and 811 745 infants (51.1%) were male. A per IQR increase (2.7 μg/m3) in prenatal ambient PM2.5 concentration was associated with a cumulative hazard ratio (CHR) of 1.12 (95% CI, 1.03-1.21) for CP. The CHR in male infants (1.14; 95% CI, 1.02-1.26) was higher compared with the CHR in female infants (1.08; 95% CI, 0.96-1.22). No specific window of susceptibility was found for prenatal PM2.5 exposure and CP in the study population. No associations or windows of susceptibility were found for prenatal NO2 or O3 exposure and CP risk.

Conclusions and relevance

In this large cohort study of singleton full term births in Canada, prenatal ambient PM2.5 exposure was associated with an increased risk of CP in offspring. Further studies are needed to explore this association and its potential biological pathways, which could advance the identification of environmental risk factors of CP in early life.

Work as a social determinant of health in high-income countries: past, present, and future

This paper, the first in a three-part Series on work and health, provides a narrative review of research into work as a social determinant of health over the past 25 years, the key emerging challenges in this field, and the implications of these challenges for future research. By use of a conceptual framework for work as a social determinant of health, we identified six emerging challenges: (1) the influence of technology on the nature of work in high-income countries, culminating in the sudden shift to telework during the COVID-19 pandemic; (2) the intersectionality of work with gender, sexual orientation, age, race, ethnicity, migrant status, and socioeconomic status as codeterminants of health disparities; (3) the arrival in many Organisation for Economic Co-operation and Development countries of large migrant labour workforces, who are often subject to adverse working conditions and social exclusion; (4) the development of precarious employment as a feature of many national labour markets; (5) the phenomenon of working long and irregular hours with potential health consequences; and (6) the looming threat of climate change's effects on work. We conclude that profound changes in the nature and availability of work over the past few decades have led to widespread new psychosocial and physical exposures that are associated with adverse health outcomes and contribute to increasing disparities in health. These new exposures at work will require novel and creative methods of data collection for monitoring of their potential health impacts to protect the workforce, and for new research into better means of occupational health promotion and protection. There is also an urgent need for a better integration of occupational health within public health, medicine, the life sciences, and the social sciences, with the work environment explicitly conceptualised as a major social determinant of health.

Neighborhood conditions and birth outcomes: Understanding the role of perceived and extrinsic measures of neighborhood quality

Living in a disadvantaged neighborhood has been associated with adverse birth outcomes. Most prior studies have conceptualized neighborhoods using census boundaries and few have examined the role of neighborhood perceptions, which may better capture the neighborhood environment. In the present study, we examined associations between extrinsic and perceived neighborhood quality measures and adverse birth outcomes.

Methods

Participants resided in the San Francisco Bay Area of California and were enrolled in Chemicals in Our Bodies, a prospective birth cohort (N = 817). The Index of Concentration at the Extremes (ICE) for income, Area Deprivation Index (ADI), and the Urban Displacement Project's measure of gentrification were included as census block group-level extrinsic neighborhood quality measures. Poor perceived neighborhood quality was assessed using an interview questionnaire. Linear regression models were utilized to examine associations between extrinsic and perceived neighborhood quality measures, and gestational age and birthweight for gestational age z-scores. Covariates in adjusted models were chosen via a directed acyclic graph (DAG) and included maternal age, education, and marital status.

Results

In adjusted models, having poor perceived neighborhood quality was associated with higher birthweight z-scores, relative to those who did not perceive their neighborhood as poor quality (β = 0.21, 95% confidence intervals = 0.01, 0.42). Relative to the least disadvantaged tertile, the upper tertile of the ADI was associated with a modest reduction in gestational age (β = -0.35, 95% confidence intervals = -0.67, -0.02).

Conclusions

In the Chemicals in Our Bodies study population, extrinsic and perceived neighborhood quality measures were inconsistently associated with adverse birth outcomes.

Suriyeli mülteci ve türk kadınlarının perinatal eğilimleri ve obstetrik sonuçları

Aim: The impact of migration on health is far-reaching, making migrant populations particularly vulnerable, fueling health inequalities and resulting in serious implications for global health. The aim of our study to assess antenatal care, pregnancy and neonatal outcomes of Syrian refugee women in Turkiye. Material and Methods: Syrian and Turkish pregnants who delivered between 2013-2019 were recruited and categorized into groups according to maternal age at delivery. First trimester combined test, second trimester triple test, preterm delivery, maternal anemia; neonatal stillbirth, APGAR scores, birth weight and breastfeeding status were assessed. Results: 4992 Syrian and 6846 Turkish pregnants were included. Maternal anemia was higher in Turkish patients in 20-34 and ≥35 groups. First trimester combined test, APGAR scores and birth weights were lower in Syrian women. Preterm rates higher in Turkish patients in only 20-34 age group. Second-trimester triplet tests were only higher in Turkish women in ≥35 age group. Low birth weight was higher in younger Syrian patients. Satisfying breastfeeding results were found in Syrian women. Conclusion: Our study stated that Syrian women are at risk of low birth weight in adolescent and 20-34 age groups and low rates in first trimester combined test in all age groups. However decreased risk of pregnancy complications such as maternal anemia, preterm delivery, cesarean delivery and satisfying breastfeeding results were found in Syrian patients.

Spaces of Segregation and Health: Complex Associations for Black Immigrant and US-Born Mothers in New York City

Black immigrants are a growing proportion of the Black population in the USA, and despite the fact that they now comprise nearly a quarter of Black urban residents, few studies address the relationships between racial segregation and maternal and birth outcomes among Black immigrants. In this study of birth outcomes among US-born and immigrant Black mothers in New York City between 2010 and 2014, we applied multilevel models, assessing the association between segregation (measured through a novel kernel-based measure of local segregation) and adverse birth outcomes (preterm birth (PTB) and low birth weight (LBW; < 2500 g)) among African-born, Caribbean-born, and US-born Black mothers. We found that African-born and Caribbean/Latin American-born Black mothers had a significantly lower incidence of PTB compared with US-born Black mothers (7.0 and 10.1, respectively, compared with 11.2 for US-born mothers). We also found disparities in the incidence of infant LBW by nativity, with the highest incidence among infants born to US-born mothers (10.9), compared with African-born (6.9) and Caribbean-born mothers (9.0). After adjusting for maternal (maternal age; higher rates of reported drug use and smoking) and contextual characteristics (neighborhood SES; green space access), we found that maternal residence in an area with high Black segregation increases the likelihood of PTB and LBW among US-born and Caribbean-born Black mothers. In contrast, the association between segregation and birth outcomes was insignificant for African-born mothers. Associations between tract-level socioeconomic disadvantage and birth outcomes also varied across groups, with only US-born Black mothers showing the expected positive association with risk of PTB and LBW.

Neighborhood environmental exposures and incidence of attention deficit/hyperactivity disorder: A population-based cohort study

BACKGROUND

Emerging studies have associated low greenspace and high air pollution exposure with risk of child attention deficit/hyperactivity disorder (ADHD). Population-based studies are limited, however, and joint effects are rarely evaluated. We investigated associations of ADHD incidence with greenspace, air pollution, and noise in a population-based birth cohort.

METHODS

We assembled a cohort from administrative data of births from 2000 to 2001 (N ∼ 37,000) in Metro Vancouver, Canada. ADHD was identified by hospital records, physician visits, and prescriptions. Cox proportional hazards models were applied to assess associations between environmental exposures and ADHD incidence adjusting for available covariates. Greenspace was estimated using vegetation percentage derived from linear spectral unmixing of Landsat imagery. Fine particulate matter (PM_2.5) and nitrogen dioxide (NO₂) were estimated using land use regression models; noise was estimated using a deterministic model. Exposure period was from birth until the age of three. Joint effects of greenspace and PM_2.5 were analysed in two-exposure models and by categorizing values into quintiles.

RESULTS

During seven-year follow-up, 1217 ADHD cases were diagnosed. Greenspace was associated with lower incidence of ADHD (hazard ratio, HR: 0.90 [0.81-0.99] per interquartile range increment), while PM_2.5 was associated with increased incidence (HR: 1.11 [1.06-1.17] per interquartile range increment). NO₂ (HR: 1.01 [0.96, 1.07]) and noise (HR: 1.00 [0.95, 1.05]) were not associated with ADHD. There was a 50% decrease in the HR for ADHD in locations with the lowest PM_2.5 and highest greenspace exposure, compared to a 62% increase in HR in locations with the highest PM_2.5 and lowest greenspace exposure. Effects of PM_2.5 were attenuated by greenspace in two-exposure models.

CONCLUSIONS

We found evidence suggesting environmental inequalities where children living in greener neighborhoods with low air pollution had substantially lower risk of ADHD compared to those with higher air pollution and lower greenspace exposure.

Neighborhood poverty, intergenerational mobility, and early developmental health in a population birth cohort

Living in a neighborhood with high levels of intergenerational mobility is associated with better childhood cognition and behavior as well as adult health. Nevertheless, it is unclear if such differences originate earlier, and thus if neighborhood intergenerational mobility is associated with health differences at birth. To address this question, we examined whether neighborhood intergenerational mobility, independent of neighborhood poverty, was associated with low birth weight (LBW) in a population-based cohort of singleton children born in California in 2017 (n = 426,873). Although increased neighborhood mobility was associated with a decreased likelihood of LBW, it was no longer associated with LBW (OR = 0.98, CI = 0.96, 1.00) after adjusting for neighborhood poverty. Meanwhile, neighborhood poverty was associated with LBW (OR = 1.04, CI = 1.02, 1.05) after accounting for mobility, with the odds of LBW 9.4% higher among children born where neighborhood poverty was in the 90th percentile compared with children born where neighborhood poverty was in the 10th percentile. Findings indicate that neighborhood poverty, but not intergenerational mobility, is a robust and independent correlate of increased LBW births, and thus early developmental health. These findings also suggest that the role of neighborhood intergenerational mobility in child and adult health outcomes may emerge later in development, independent of LBW, or that the role of neighborhood intergenerational mobility in LBW may be indirectly mediated through exposure to neighborhood poverty.

Neighbourhood material deprivation and severe maternal morbidity: a population-based cohort study in Ontario, Canada

OBJECTIVES

Rates of age-associated severe maternal morbidity (SMM) have increased in Canada, and an association with neighbourhood income is well established. Our aim was to examine SMM trends according to neighbourhood material deprivation quintile, and to assess whether neighbourhood deprivation effects are moderated by maternal age.

DESIGN, SETTING AND PARTICIPANTS

A population-based retrospective cohort study using linked administrative databases in Ontario, Canada. We included primiparous women with a live birth or stillbirth at ≥20 weeks' gestational age.

PRIMARY OUTCOME

SMM from pregnancy onset to 42 days postpartum. We calculated SMM rate differences (RD) and rate ratios (RR) by neighbourhood material deprivation quintile for each of four 4-year cohorts from 1 April 2002 to 31 March 2018. Log-binomial multivariable regression adjusted for maternal age, demographic and pregnancy-related variables.

RESULTS

There were 1 048 845 primiparous births during the study period. The overall rate of SMM was 18.0 per 1000 births. SMM rates were elevated for women living in areas with high material deprivation. In the final 4-year cohort, the RD between women living in high vs low deprivation neighbourhoods was 3.91 SMM cases per 1000 births (95% CI: 2.12 to 5.70). This was higher than the difference observed during the first 4-year cohort (RD 2.09, 95% CI: 0.62 to 3.56). SMM remained associated with neighbourhood material deprivation following multivariable adjustment in the pooled sample (RR 1.16, 95% CI: 1.11 to 1.21). There was no evidence of interaction with maternal age.

CONCLUSION

SMM rate increases were more pronounced for primiparous women living in neighbourhoods with high material deprivation compared with those living in low deprivation areas. This raises concerns of a widening social gap in maternal health disparities and highlights an opportunity to focus risk reduction efforts toward disadvantaged women during pregnancy and postpartum.

The geography of ethnoracial low birth weight inequalities in the United States

In this article, we describe, decompose, and examine correlates of the geography of ethnoracial inequalities in low birth weight (LBW) in the United States. Drawing on the population of singleton births to U.S.-born White, Black, Latinx, and Native American parents in the first decade of the twenty-first century (N = 28.2 million births), we calculate county-level LBW rates and rate ratios. Results demonstrate a stark racial hierarchy in which Black infants experience the most significant disadvantage, but we also document substantial local-level variation organized in what we call a regionalized patchwork of inequality, with high-disparity counties bordering low-disparity counties coupled with regional clustering. Examining the component parts of local disparities - the LBW rates for Whites and groups of color - we find strong evidence that spatial variation in ethnoracial LBW inequalities is driven by greater variation in infants of color's health across counties relative to Whites. Further, LBW rates for groups of color are only weakly to moderately correlated with Whites' LBW rates, indicating that the same contexts can produce racially divergent health outcomes. Examining contextual factors that predict LBW disparities, we find that more segregated, socioeconomically unequal, and urban counties have larger LBW disparities. We conclude by positing an approach to health disparities that conceptualizes ethnoracial differences in health as fundamentally relational and spatial phenomena produced by systems of White advantage.

Hot spots for pediatric asthma emergency department visits in Ottawa, Canada

OBJECTIVE

Pediatric asthma emergency department (ED) visits and repeat visits place a substantial burden on healthcare. National and provincial level studies demonstrate geographic variation in asthma ED visits and links to marginalization, but preclude translation into practical targeting of healthcare delivery. It is important to understand the relationship between pediatric asthma ED visits and marginalization at a more granular level. To map the city-level geographic variation in pediatric asthma ED visit and re-visit rates at the Children's Hospital of Eastern Ontario (CHEO) in Ottawa, Canada and the relationship with marginalization.

METHODS

We performed a single center retrospective cohort study of children ages 1-17 with one or more ED visits for asthma at the CHEO in Ottawa. Using postal codes, we linked patients to census tracts. Per census tract, we mapped pediatric asthma ED visit and re-visit rates within one year and identified overlap with the Ontario Marginalization Index.

RESULTS

Of 1,620 children with an index ED visit, 18.5% had a repeat ED visit. We identified 10 hot spot census tracts each for pediatric asthma ED visit and re-visit rates. We identified an overlap between urban hot spots and areas with high ethnic concentration or low dependency.

CONCLUSION

At a granular, city-wide level, pediatric asthma ED visit and re-visit rates are heterogeneous. Urban hot spots, in contrast to rural, have more overlap with marginalization, especially ethnic concentration. These methods can be used in other jurisdictions to inform practical community strategies for geographically-targeted prevention of pediatric asthma-related ED visits in vulnerable areas.Abbreviations:ED:Emergency department;CHEO:Children's Hospital of Eastern Ontario;PRAM:Pediatric Respiratory Assessment Measure;ON-Marg:Ontario Marginalization Index;SES:Socioeconomic status;US:United States.

Supplemental data for this article can be accessed at publisher's website.

Maternal Experience of Multiple Hardships and Fetal Growth: Extending Environmental Mixtures Methodology to Social Exposures

BACKGROUND

Women can be exposed to a multitude of hardships before and during pregnancy that may affect fetal growth, but previous approaches have not analyzed them jointly as social exposure mixtures.

METHODS

We evaluated the independent, mutually adjusted, and pairwise joint associations between self-reported hardships and birthweight for gestational age z-scores in the Chemicals in Our Bodies-2 prospective birth cohort (N = 510) using G-computation. We examined financial hardship, food insecurity, job strain, poor neighborhood environment, low community standing, caregiving, high burden of stressful life events, and unplanned pregnancy collected via questionnaire administered in the second trimester of pregnancy. We used propensity scores to ensure our analyses had sufficient data support and estimated absolute differences in outcomes.

RESULTS

Food insecurity was most strongly associated with reduced birthweight for gestational age z-scores individually, with an absolute difference of -0.16, 95% confidence interval (CI) -0.45, 0.14. We observed an unexpected increase in z-scores associated with poor perceived neighborhood environment (0.18, 95% CI -0.04, 0.41). Accounting for coexposures resulted in similar findings. The pairwise joint effects were strongest for food insecurity in combination with unplanned pregnancy (-0.45, 95% CI -0.93, 0.02) and stressful life events (-0.42, 95% CI -0.90, 0.05). Poor neighborhood environment in combination with caregiving was associated with an increase in z-scores (0.47, 95% CI -0.01, 0.95).

CONCLUSIONS

Our results are consistent with the hypothesis that experiencing food insecurity during pregnancy, alone and in combination with stressful life events and unplanned pregnancy, may affect fetal growth.

Cross-classified multilevel models (CCMM) in health research: A systematic review of published empirical studies and recommendations for best practices

Recognizing that health outcomes are influenced by and occur within multiple social and physical contexts, researchers have used multilevel modeling techniques for decades to analyze hierarchical or nested data. Cross-Classified Multilevel Models (CCMM) are a statistical technique proposed in the 1990s that extend standard multilevel modeling and enable the simultaneous analysis of non-nested multilevel data. Though use of CCMM in empirical health studies has become increasingly popular, there has not yet been a review summarizing how CCMM are used in the health literature. To address this gap, we performed a scoping review of empirical health studies using CCMM to: (a) evaluate the extent to which this statistical approach has been adopted; (b) assess the rationale and procedures for using CCMM; and (c) provide concrete recommendations for the future use of CCMM. We identified 118 CCMM papers published in English-language literature between 1994 and 2018. Our results reveal a steady growth in empirical health studies using CCMM to address a wide variety of health outcomes in clustered non-hierarchical data. Health researchers use CCMM primarily for five reasons: (1) to statistically account for non-independence in clustered data structures; out of substantive interest in the variance explained by (2) concurrent contexts, (3) contexts over time, and (4) age-period-cohort effects; and (5) to apply CCMM alongside other techniques within a joint model. We conclude by proposing a set of recommendations for use of CCMM with the aim of improved clarity and standardization of reporting in future research using this statistical approach.

Perinatal care experiences of Muslim women in Northwestern Ontario, Canada: A qualitative study

PROBLEM AND BACKGROUND

Although the number of Muslim women in Canada and northwestern Ontario (NWO) is increasing, few studies have focused on their experiences of perinatal health care. Extant research has highlighted discrimination and care that lacks respect for cultural and religious norms. These factors may limit access to health services and increase unfavorable maternal and child health outcomes.

AIM

To explore the perinatal health care experiences of Muslim women in NWO.

METHODS

A qualitative, descriptive study used purposive and snowball sampling to recruit a sample of 19 Muslim mothers. Ssemistructured interviews were conducted, audio recorded, transcribed verbatim, and analyzed thematically.

FINDINGS

The mothers' experiences were categorized into four themes: women's choices and preferences of health care providers (HCPs); attitudes toward prenatal classes and education; husbands' involvement and support in the birthing process; and challenges to optimal care.

DISCUSSION AND CONCLUSION

The findings show that NWO Muslim women's experiences were generally positive and their care choices and preferences were shaped by their religious beliefs and cultural practices. Factors that enhanced their experiences were HCPs' awareness of and respect for the women's religious and cultural beliefs and practices. However, the women lacked personal knowledge of a range of care options and services. Respecting Muslim women's religious and cultural beliefs and practices will enhance their experience of care. Equity in access to quality services, care, and outcomes can be further enhanced if Muslim women are informed about the range of care options and services as early in their pregnancies as possible.

Emergency Department as a First Contact for Mental Health Problems in Children and Youth

OBJECTIVE

To characterize youth who use the emergency department (ED) as a "first contact" for mental health (MH) problems.

METHOD

This was a population-based cross-sectional cohort study using linked health and demographic administrative datasets of youth 10 to 24 years of age with an incident MH ED visit from April 1, 2010, to March 31, 2014, in Ontario, Canada. We modeled the association of demographic, clinical, and health service use characteristics with having no prior outpatient MH care in the preceding 2-year period ("first contact") using modified Poisson models.

RESULTS

Among 118,851 youth with an incident mental health ED visit, 14.0% were admitted. More than half (53.5%) had no prior outpatient MH care, and this was associated with younger age (14-17 versus 22-24 years old: risk ratio [RR] = 1.09, 95% CI = 1.07-1.10), rural residence (RR = 1.16, 95% CI = 1.14-1.18), lowest versus highest income quintile (RR = 1.04, 95% CI = 1.03-1.06), and refugee immigrants (RR = 1.17, 95% CI = 1.13-1.21) and other immigrants (RR = 1.10, 95% CI = 1.08-1.13) versus nonimmigrants. The 5.1% of the cohort without a usual provider of primary care had the highest risk of first contact (RR = 1.78, 95% CI = 1.77-1.80). A history of low-acuity ED use and individuals whose primary care physicians were in the lowest tertile for mental health visit volumes were associated with higher risk.

CONCLUSION

More than half of youth requiring ED care had not previously sought outpatient MH care. Associations with multiple markers of primary care access characteristics suggest that timely primary care could prevent some of these visits.

Variation in Physician Spending and Association With Patient Outcomes

IMPORTANCE

While the substantial variation in health care spending across regions and hospitals is well known, key clinical decisions are ultimately made by physicians. However, the degree to which spending varies across physicians and the clinical consequences of that variation are unknown.

OBJECTIVE

To investigate variation in spending across physicians and its association with patient outcomes.

DESIGN, SETTING, AND PARTICIPANTS

For this retrospective data analysis, we analyzed a 20% random sample of Medicare fee-for-service beneficiaries 65 years and older who were hospitalized with a nonelective medical condition and treated by a general internist between January 1, 2011, and December 31, 2014. We first quantified the proportion of variation in Medicare Part B spending attributable to hospitals, physicians, and patients. We then examined the association between physician spending and patient outcomes, adjusted for patient and physician characteristics and hospital fixed effects (effectively comparing physicians within the same hospital). Our primary analysis focused on hospitalist physicians, whose patients are plausibly quasirandomized within a hospital based on physician work schedule. A secondary analysis focused on general internists overall. To ensure that patient illness severity did not directly affect physician spending estimates, we calculated physicians' spending levels in 2011 through 2012 and examined outcomes of their patients in 2013 and 2014.

EXPOSURES

Physicians' adjusted Part B spending level in 2011 through 2012.

MAIN OUTCOMES AND MEASURES

Patients' 30-day mortality and readmission rates in 2013 and 2014.

RESULTS

To determine the amount of variation across physicians we included 485 016 hospitalizations treated by 21 963 physicians at 2837 acute care hospitals for the analysis of hospitalists and 839 512 hospitalizations treated by 50 079 physicians at 3195 acute care hospitals for the analysis of general internists. Variation in spending across physicians within hospital was larger than variation across hospitals (for hospitalists, 8.4% across physicians vs 7.0% across hospitals; for general internists, 10.5% across physicians vs 6.2% across hospitals). Higher physician spending was not associated with lower 30-day mortality (adjusted odds ratio [aOR] for additional $100 in physician spending, 1.00; 95% CI, 0.98-1.01; P = .47) or readmissions (aOR, 1.00; 95% CI, 0.99-1.01; P = .54) for hospitalists within the same hospital. We observed similar patterns among general internists.

CONCLUSIONS AND RELEVANCE

Health care spending varies more across individual physicians than across hospitals. However, higher physician spending is not associated with better outcomes of hospitalized patients. Our findings suggest policies targeting both physicians and hospitals may be more effective in reducing wasteful spending than policies focusing solely on hospitals.

A Population-Based Cross-Sectional Study Comparing Breast Cancer Stage at Diagnosis between Immigrant and Canadian-Born Women in Ontario

There is limited information on stage at breast cancer diagnosis in Canadian immigrant women. We compared stage at diagnosis between immigrant women and Canadian-born women, and determined whether ethnicity was an independent factor associated with stage. 41,213 women with invasive breast cancer from 2007 to 2012 were identified from the Ontario Cancer Registry. Women were classified as either immigrants or Canadian-born by linkage with the Immigration, Refugees, and Citizenship Canada's Permanent Resident database. Women's ethnicity was classified as Chinese, South Asian, or remaining women in Ontario. Logistic regression was performed to calculate the odds ratio (OR) of being diagnosed at stage I breast cancer (versus stage II-IV). 4,353 (10.6%) women were immigrants and 36,860 (89.4%) were Canadian-born women. The mean age at breast cancer diagnosis was 53.5 years for immigrants versus 62.3 years for Canadian-born women (p < 0.0001). Immigrant women were less likely than Canadian-born women to be diagnosed with stage I breast cancers (adjusted OR = 0.85; 95% CI: 0.79-0.91; p < 0.0001). The adjusted OR of being stage I was 1.28 (95% CI: 1.14-1.43; p < 0.0001) for women of Chinese ethnicity and was 0.82 (95% CI: 0.70-0.96; p = 0.01) for women of South Asian ethnicity, compared to the remaining women in Ontario. Canadian immigrant women were less likely than Canadian-born women to be diagnosed with early-stage breast cancers. Ethnicity was a greater contributor to the stage disparity than was immigrant status. South Asian women, regardless of immigration status, might benefit from increased breast cancer awareness programs.

Scoping Review on Maternal Health among Immigrant and Refugee Women in Canada: Prenatal, Intrapartum, and Postnatal Care

The last fifteen years have seen a dramatic increase in both the childbearing age and diversity of women migrating to Canada. The resulting health impact underscores the need to explore access to health services and the related maternal health outcome. This article reports on the results of a scoping review focused on migrant maternal health within the context of accessible and effective health services during pregnancy and following delivery. One hundred and twenty-six articles published between 2000 and 2016 that met our inclusion criteria and related to this group of migrant women, with pregnancy/motherhood status, who were living in Canada, were identified. This review points at complex health outcomes among immigrant and refugee women that occur within the compelling gaps in our knowledge of maternal health during all phases of maternity. Throughout the prenatal, intrapartum, and postnatal periods of maternity, barriers to accessing healthcare services were found to disadvantage immigrant and refugee women putting them at risk for challenging maternal health outcomes. Interactions between the uptake of health information and factors related to the process of immigrant settlement were identified as major barriers. Availability of appropriate services in a country that provides universal healthcare is discussed.

Motor vehicle crashes during pregnancy and cerebral palsy during infancy: a longitudinal cohort analysis

OBJECTIVES

To assess the incidence of cerebral palsy among children born to mothers who had their pregnancy complicated by a motor vehicle crash.

DESIGN

Retrospective longitudinal cohort analysis of children born from 1 April 2002 to 31 March 2012 in Ontario, Canada.

PARTICIPANTS

Cases defined as pregnancies complicated by a motor vehicle crash and controls as remaining pregnancies with no crash.

MAIN OUTCOME

Subsequent diagnosis of cerebral palsy by age 3 years.

RESULTS

A total of 1 325 660 newborns were analysed, of whom 7933 were involved in a motor vehicle crash during pregnancy. A total of 2328 were subsequently diagnosed with cerebral palsy, equal to an absolute risk of 1.8 per 1000 newborns. For the entire cohort, motor vehicle crashes correlated with a 29% increased risk of subsequent cerebral palsy that was not statistically significant (95% CI -16 to +110, p=0.274). The increased risk was only significant for those with preterm birth who showed an 89% increased risk of subsequent cerebral palsy associated with a motor vehicle crash (95% CI +7 to +266, p=0.037). No significant increase was apparent for those with a term delivery (95% CI -62 to +79, p=0.510). A propensity score-matched analysis of preterm births (n=4384) yielded a 138% increased relative risk of cerebral palsy associated with a motor vehicle crash (95% CI +27 to +349, p=0.007), equal to an absolute increase of about 10.9 additional cases per 1000 newborns (18.2 vs 7.3, p=0.010).

CONCLUSIONS

Motor vehicle crashes during pregnancy may be associated with an increased risk of cerebral palsy among the subgroup of cases with preterm birth. The increase highlights a specific role for traffic safety advice in prenatal care.

Emergency Department Revisits by Urban Immigrant Children in Canada: A Population-Based Cohort Study

OBJECTIVES

To examine the relationship between family immigrant status and unscheduled 7-day revisits to the emergency department (ED) and to test this relationship within subgroups of immigrants by visa class (family, economic, refugee), native tongue on landing in Canada, and region of origin.

STUDY DESIGN

Population-based cohort study that used multiple linked health administrative and demographic datasets of landed immigrant and nonimmigrant children (<18 years) in urban Ontario who visited an ED and were discharged between April 2003 and March 2010. Logistic regression was used to model the odds of 7-day ED revisits with family immigrant status, with adjustment for patient and ED characteristics.

RESULTS

Of 3,322,901 initial visits to the ED, 249,648 (7.5%) resulted in a 7-day revisit. There was no significant association of immigrant status with either ED revisits or poor revisit outcomes (greater acuity visit or need for admission) in the adjusted models. Within immigrants, the odds of revisit were not associated with immigrant classes or region of origin; however, immigrants whose native tongue was not English or French had a slightly greater odds of revisiting the ED (aOR 1.05; 95% CI 1.01, 1.09). Significant predictors of revisits included younger age, greater triage acuity score, greater predilection for using an ED, daytime shifts, and greater deprivation index.

CONCLUSIONS

Immigrant children are not more likely to have short-term revisits to the ED, but there may be barriers to care related to language fluency that need to be addressed. These findings may be relevant for improving translation services in EDs.

Does Maternal Country of Birth Matter for Understanding Offspring's Birthweight? A Multilevel Analysis of Individual Heterogeneity in Sweden

Background

Many public health and epidemiological studies have found differences between populations (e.g. maternal countries of birth) in average values of a health indicator (e.g. mean offspring birthweight). However, the approach based solely on population-level averages compromises our understanding of variability in individuals’ health around the averages. If this variability is high, the exclusive study of averages may give misleading information. This idea is relevant when investigating country of birth differences in health.

Methods and Results

To exemplify this concept, we use information from the Swedish Medical Birth Register (2002–2010) and apply multilevel regression analysis of birthweight, with babies (n = 811,329) at the first, mothers (n = 571,876) at the second, and maternal countries of birth (n = 109) at the third level. We disentangle offspring, maternal and maternal country of birth components of the total offspring heterogeneity in birthweight for babies born within the normal timespan (37–42 weeks). We found that of such birthweight variation about 50% was at the baby level, 47% at the maternal level and only 3% at the maternal countries of birth level.

Conclusion

In spite of seemingly large differences in average birthweight among maternal countries of birth (range 3290–3677g), knowledge of the maternal country of birth does not provide accurate information for ascertaining individual offspring birthweight because of the high inter-offspring heterogeneity around country averages. Our study exemplifies the need for a better understanding of individual health diversity for which group averages may provide insufficient and even misleading information. The analytical approach we outline is therefore relevant to investigations of country of birth (and ethnic) differences in health in general.

Small and large size for gestational age and neighborhood deprivation measured within increasing proximity to homes

Neighborhood deprivation is consistently associated with greater risk of low birthweight. However, large birth size is increasingly relevant but overlooked in neighborhood health research, and proximity within which neighborhood deprivation may affect birth outcomes is unknown. We estimated race/ethnic-specific effects of neighborhood deprivation index (NDI) within 1, 3, 5, and 8km buffers around Oregon Pregnancy Risk Assessment Monitoring System (n=3716; 2004-2007) respondents׳ homes on small and large for gestational age (SGA, LGA). NDI was positively associated with LGA and SGA in most race/ethnic groups. The results varied little across the four buffer sizes.

Maternal organ donation and acute injuries in surviving children

PURPOSE

The purpose of this study is to test whether maternal deceased organ donation is associated with rates of subsequent acute injuries among surviving children after their mother's death.

METHODS

This is a longitudinal cohort analysis of children linked to mothers who died of a catastrophic brain event in Ontario, Canada, between April 1988 and March 2012. Surviving children were distinguished by whether their mother was an organ donor after death. The primary outcome was an acute injury event in surviving children during the year after their mother's death.

RESULTS

Surviving children (n=454) had a total of 293 injury events during the year after their mother's death, equivalent to an average of 65 events per 100 children per year and a significant difference comparing children of mothers who were organ donors to children of mothers who were not organ donors (21 vs 82, P<.001). This difference in subsequent injury rates between groups was equal to a 76% relative reduction in risk (95% confidence interval, 62%-85%).

CONCLUSIONS

Deceased organ donation was associated with a reduction in excess acute injuries among surviving children after their mother's death. An awareness of this positive association provides some reassurance about deceased organ donation programs.

Association between socio-economic status and hemoglobin A1c levels in a Canadian primary care adult population without diabetes

BACKGROUND

Hgb A1c levels may be higher in persons without diabetes of lower socio-economic status (SES) but evidence about this association is limited; there is therefore uncertainty about the inclusion of SES in clinical decision support tools informing the provision and frequency of Hgb A1c tests to screen for diabetes. We studied the association between neighborhood-level SES and Hgb A1c in a primary care population without diabetes.

METHODS

This is a retrospective study using data routinely collected in the electronic medical records (EMRs) of forty six community-based family physicians in Toronto, Ontario. We analysed records from 4,870 patients without diabetes, age 45 and over, with at least one clinical encounter between January 1st 2009 and December 31st 2011 and one or more Hgb A1c report present in their chart during that time interval. Residential postal codes were used to assign neighborhood deprivation indices and income levels by quintiles. Covariates included elements known to be associated with an increase in the risk of incident diabetes: age, gender, family history of diabetes, body mass index, blood pressure, LDL cholesterol, HDL cholesterol, triglycerides, and fasting blood glucose.

RESULTS

The difference in mean Hgb A1c between highest and lowest income quintiles was -0.04% (p = 0.005, 95% CI -0.07% to -0.01%), and between least deprived and most deprived was -0.05% (p = 0.003, 95% CI -0.09% to -0.02%) for material deprivation and 0.02% (p = 0.2, 95% CI -0.06% to 0.01%) for social deprivation. After adjustment for covariates, a marginally statistically significant difference in Hgb A1c between highest and lowest SES quintile (p = 0.04) remained in the material deprivation model, but not in the other models.

CONCLUSIONS

We found a small inverse relationship between Hgb A1c and the material aspects of SES; this was largely attenuated once we adjusted for diabetes risk factors, indicating that an independent contribution of SES to increasing Hgb A1c may be limited. This study does not support the inclusion of SES in clinical decision support tools that inform the use of Hgb A1c for diabetes screening.

The association between socioeconomic status and survival among children with Hodgkin and non-Hodgkin lymphomas in a universal health care system

BACKGROUND

The association between socioeconomic status (SES) and cancer survival has been studied extensively in adults. However, little is known about this relationship in the pediatric population, specifically in jurisdictions with universal health care insurance programs. Our aim was to determine whether lower SES is associated with poorer survival in pediatric Hodgkin (HL) and non-Hodgkin lymphoma (NHL) patients in Ontario.

PROCEDURE

All incident cases of HL and NHL in children between 0 and 14 years old diagnosed in Ontario between January 1st, 1985 and December 31st, 2006 were identified through the Pediatric Oncology Group of Ontario Networked Information System. Neighborhood income quintile and material deprivation quintile at diagnosis were used as proxies for SES. Cox proportional hazards regressions were used to assess the association between SES and the risk of event-free or overall survival.

RESULTS

A total of 692 patients were included in the analysis: 302 HL and 390 NHL. SES was not associated with survival (overall or event-free) among HL and NHL patients (P > 0.05 for all four comparisons, i.e., HL/NHL, EFS/OS) after adjustment for age, sex, period of diagnosis, and disease stage. There were no differences in the distribution of disease stage across SES strata at the time of diagnosis. Similarly, the distribution of deaths among long-term survivors (survived ≥5 years from diagnosis) did not differ across SES strata (P > 0.05).

CONCLUSIONS

SES was not associated with risk of death among pediatric HL and NHL patients in Ontario. This was consistent through the cancer trajectory, including diagnosis, treatment, and survivorship.

Is asthma a vanishing disease? A study to forecast the burden of asthma in 2022

Background

Recent evidence regarding temporal trends of asthma burden has not been consistent, with some countries reporting decreases in prevalence of asthma. In Ontario, the province in Canada with the highest population, the prevalence of asthma rose at a rate of 0.5% per year between 1996 and 2005. These estimates were based on population-based health services use data spanning more than a decade and provide a powerful source to forecast the trends of asthma burden. The objective of this study was to use observed population trends data of asthma incidence and prevalence to forecast future disease burden.

Methods

The Ontario Asthma Surveillance Information System (OASIS) used health administrative databases to identify and track all individuals in the province with asthma. Individuals with asthma identified between April 1, 1996 and March 31, 2010 were included. Exponential smoothing models were applied to annual data to project incidence to the year 2022, prevalence was estimated by applying the cumulative projected incidence to the projected population.

Results

While asthma incidence is falling, the absolute number of prevalent cases will continue to rise. We projected that almost 1 in 8 individuals in Ontario will have asthma by the year 2022, suggesting that asthma will continue to be a major burden on individuals and the health care system.

Conclusions

These projections will help inform health care planners and decision-makers regarding resource allocation to optimize asthma outcomes.

Linguistic isolation in the home and community: Protection or risk for young children?

Studies of immigrant adaptation in the United States emphasize the importance of duration of residence, language use, location of schooling and other factors related to the migration process in determining outcomes for immigrants. Research also points to the variability of socioeconomic mobility among immigrants and their descendants across receiving contexts encountered in the United States. This paper extends this model to young children and examines how the linguistic environment of the family and the community interact to produce differential developmental outcomes. The analyses rely on data from the Early Childhood Longitudinal Study-Birth Cohort (ECLS-B) and 2000 US Census. Children's cognitive scores vary considerably by mothers' nativity and household linguistic isolation; a result that is largely influenced by the greater likelihood of living in poverty for children in linguistically isolated homes. The level of linguistic isolation in the community is also associated with cognitive scores but the greatest variation in scores across communities occurs among children of US born mothers.

A population-level analysis of birth weight indices in Peel Region, Ontario: the impact of ethnic diversity

OBJECTIVES

The purpose of this paper is to examine whether the elevated rate of low birth weight (LBW) in the Region of Peel, Ontario can be attributed to the high proportion of immigrants in the population. In addition, we examined how the infant birth weight distribution in Peel differs by maternal region of birth.

METHODS

Provincial live birth registration data were used to compare rates of LBW, preterm birth and small-for-gestational-age (SGA) births in Peel and Ontario for the years 2002 through 2006 by maternal region of birth. Birth weight for gestational age curves were developed for singletons and were specific for infant sex and maternal region of birth using the lambda-mu-sigma (LMS) method. Quantile regression was used to examine whether the median birth weight at term (37 to 42 weeks) differed by maternal region of birth.

RESULTS

The rate of LBW was higher in Peel than in Ontario (6.8% and 6.0%, respectively). This is the result of a higher SGA rate and not due to differences in rates of preterm birth. Infants of immigrant mothers had significantly lower median birth weights at all gestations, showing that the birth weight distribution among infants of immigrant mothers is shifted towards lower birth weights.

CONCLUSION

At the population level, the shifted birth weight distribution among singleton infants of immigrant mothers has significant impact on the LBW rate observed in Peel.

Neighborhood inequalities in adverse pregnancy outcomes in an urban setting in Spain: a multilevel approach

The aim of the present study was to describe socioeconomic inequalities in low birth weight (LBW), premature birth (PM) and small size for gestational age at birth (SGA) between 2000 and 2005 in Barcelona, Spain, jointly evaluating the effect of mother's country of origin, and neighborhood of residence socioeconomic level measured using unemployment and educational level. We performed a cross-sectional study of births to mothers aged 12-49 years who were residents in the city of Barcelona in 2000-2005, analyzing adverse pregnancy outcomes (n = 61,676). Weighted multilevel logistic regression models were fitted with individual data on level 1 and neighborhood data on level 2, to obtain adjusted odds ratios (aOR) with 95% confidence intervals and residual variance. Individually, pregnancy outcomes are more favorable in births to older mothers and to mothers from Maghrib and Central and South America than from developed countries (including Spain) or from other developing countries. After adjusting for individual variables, poor pregnancy outcomes were associated with poor neighborhoods (more unemployment was associated to LBW: aOR = 1.56; PM aOR = 1.51; SGA aOR = 1.66). The same trend was observed for associations with illiteracy rate. The present study shows that there are socioeconomic inequalities in adverse pregnancy outcomes in the city of Barcelona. One of the main challenges in perinatal health continues to be the reduction of adverse pregnancy outcomes in the city.

Development of the Canadian Marginalization Index: a new tool for the study of inequality

OBJECTIVES

Area-based measures of socio-economic status are increasingly used in population health research. Based on previous research and theory, the Canadian Marginalization Index (CAN-Marg) was created to reflect four dimensions of marginalization: residential instability, material deprivation, dependency and ethnic concentration. The objective of this paper was threefold: to describe CAN-Marg; to illustrate its stability across geographic area and time; and to describe its association with health and behavioural problems.

METHODS

CAN-Marg was created at the dissemination area (DA) and census tract level for census years 2001 and 2006, using factor analysis. Descriptions of 18 health and behavioural problems were selected using individual-level data from the Canadian Community Health Survey (CCHS) 3.1 and 2007/08. CAN-Marg quintiles created at the DA level (2006) were assigned to individual CCHS records. Multilevel logistic regression modeling was conducted to examine associations between marginalization and CCHS health and behavioural problems.

RESULTS

The index demonstrated marked stability across time and geographic area. Each of the four dimensions showed strong and significant associations with the selected health and behavioural problems, and these associations differed depending on which of the dimensions of marginalization was examined.

CONCLUSION

CAN-Marg is a census-based, empirically derived and theoretically informed tool designed to reflect a broader conceptualization of Canadian marginalization.

Development of the Canadian Marginalization Index: a new tool for the study of inequality

OBJECTIVES

Area-based measures of socio-economic status are increasingly used in population health research. Based on previous research and theory, the Canadian Marginalization Index (CAN-Marg) was created to reflect four dimensions of marginalization: residential instability, material deprivation, dependency and ethnic concentration. The objective of this paper was threefold: to describe CAN-Marg; to illustrate its stability across geographic area and time; and to describe its association with health and behavioural problems.

METHODS

CAN-Marg was created at the dissemination area (DA) and census tract level for census years 2001 and 2006, using factor analysis. Descriptions of 18 health and behavioural problems were selected using individual-level data from the Canadian Community Health Survey (CCHS) 3.1 and 2007/08. CAN-Marg quintiles created at the DA level (2006) were assigned to individual CCHS records. Multilevel logistic regression modeling was conducted to examine associations between marginalization and CCHS health and behavioural problems.

RESULTS

The index demonstrated marked stability across time and geographic area. Each of the four dimensions showed strong and significant associations with the selected health and behavioural problems, and these associations differed depending on which of the dimensions of marginalization was examined.

CONCLUSION

CAN-Marg is a census-based, empirically derived and theoretically informed tool designed to reflect a broader conceptualization of Canadian marginalization.

Development of the Canadian Marginalization Index: a new tool for the study of inequality

OBJECTIVES

Area-based measures of socio-economic status are increasingly used in population health research. Based on previous research and theory, the Canadian Marginalization Index (CAN-Marg) was created to reflect four dimensions of marginalization: residential instability, material deprivation, dependency and ethnic concentration. The objective of this paper was threefold: to describe CAN-Marg; to illustrate its stability across geographic area and time; and to describe its association with health and behavioural problems.

METHODS

CAN-Marg was created at the dissemination area (DA) and census tract level for census years 2001 and 2006, using factor analysis. Descriptions of 18 health and behavioural problems were selected using individual-level data from the Canadian Community Health Survey (CCHS) 3.1 and 2007/08. CAN-Marg quintiles created at the DA level (2006) were assigned to individual CCHS records. Multilevel logistic regression modeling was conducted to examine associations between marginalization and CCHS health and behavioural problems.

RESULTS

The index demonstrated marked stability across time and geographic area. Each of the four dimensions showed strong and significant associations with the selected health and behavioural problems, and these associations differed depending on which of the dimensions of marginalization was examined.

CONCLUSION

CAN-Marg is a census-based, empirically derived and theoretically informed tool designed to reflect a broader conceptualization of Canadian marginalization.

The modifiable areal unit problem (MAUP) in the relationship between exposure to NO2 and respiratory health

Background

Many Canadian population health studies, including those focusing on the relationship between exposure to air pollution and health, have operationalized neighbourhoods at the census tract scale. At the same time, the conceptualization of place at the local scale is one of the weakest theoretical aspects in health geography. The modifiable areal unit problem (MAUP) raises issues when census tracts are used as neighbourhood proxies, and no other alternate spatial structure is used for sensitivity analysis. In the literature, conclusions on the relationship between NO₂ and health outcomes are divided, and this situation may in part be due to the selection of an inappropriate spatial structure for analysis. Here, we undertake an analysis of NO₂ and respiratory health in Ottawa, Canada using three different spatial structures in order to elucidate the effects that the spatial unit of analysis can have on analytical results.

Results

Using three different spatial structures to examine and quantify the relationship between NO₂ and respiratory morbidity, we offer three main conclusions: 1) exploratory spatial analytical methods can serve as an indication of the potential effect of the MAUP; 2) OLS regression results differ significantly using different spatial representations, and this could be a contributing factor to the lack of consensus in studies that focus on the relation between NO₂ and respiratory health at the area-level; and 3) the use of three spatial representations confirms no measured effect of NO₂ exposure on respiratory health in Ottawa.

Conclusions

Area units used in population health studies should be delineated so as to represent the a priori scale of the expected scale interaction between neighbourhood processes and health. A thorough understanding of the role of the MAUP in the study of the relationship between NO₂ and respiratory health is necessary for research into disease pathways based on statistical models, and for decision-makers to assess the scale at which interventions will have maximum benefit. In general, more research on the role of spatial representation in health studies is needed.

Does time since immigration modify neighborhood deprivation gradients in preterm birth? A multilevel analysis

Immigrants' health is jointly influenced by their pre- and post-migration exposures, but how these two influences operate with increasing duration of residence has not been well-researched. We aimed to examine how the influence of maternal country of birth and neighborhood deprivation effects, if any, change over time since migration and how neighborhood effects among immigrants compare with those observed in the Canadian-born population. Birth data from Ontario hospital records (2002-2007) were linked with an official Canadian immigration database (1985-2000). The outcome measure was preterm birth. Neighborhoods were ranked according to a neighborhood deprivation index developed for Canadian urban areas and collapsed into tertiles of approximately equal size. Time since immigration was measured from the date of arrival to Canada to the date of delivery, ranging from 1 to 22 years. We used cross-classified random effect models to simultaneously account for the membership of births (N = 83,233) to urban neighborhoods (N = 1,801) and maternal countries of birth (N = 168). There were no differences in preterm birth between neighborhood deprivation tertiles among immigrants with less than 15 years of residence. Among immigrants with 15 years of stay or more, the adjusted absolute risk difference (ARD%, 95% confidence interval) between high-deprived (tertile 3) and low-deprived (tertile 1) neighborhoods was 1.86 (0.68, 2.98), while the ARD% observed among the Canadian-born (N = 314,237) was 1.34 (1.11, 1.57). Time since migration modifies the neighborhood deprivation gradient in preterm birth among immigrants living in Ontario cities. Immigrants reached the level of inequalities in preterm birth observed at the neighborhood level among the Canadian-born after 14 years of stay, but neighborhoods did not influence preterm birth among more recent immigrants, for whom the maternal country of birth was more predictive of preterm birth.

The association between neighbourhoods and adverse birth outcomes: a systematic review and meta-analysis of multi-level studies

Many studies have examined the role of neighbourhood environment on birth outcomes but, because of differences in study design and modelling techniques, have found conflicting results. Seven databases were searched (1900-2010) for multi-level observational studies related to neighbourhood and pregnancy/birth. We identified 1502 articles of which 28 met all inclusion criteria. Meta-analysis was used to examine the association between neighbourhood income and low birthweight. Most studies showed a significant association between neighbourhood factors and birth outcomes. A significant pooled association was found for the relationship between neighbourhood income and low birthweight [odds ratio = 1.11, 95% confidence interval: 1.02, 1.20] whereby women who lived in low income neighbourhoods had significantly higher odds of having a low birthweight infant. This body of literature was found to consistently document significant associations between neighbourhood factors and birth outcomes. The consistency of findings from observational studies in this area indicates a need for causal studies to determine the mechanisms by which neighbourhoods influence birth outcomes.

Neighborhood deprivation and adverse birth outcomes among diverse ethnic groups

PURPOSE

Living in a socioeconomically deprived neighborhood has been associated with an increased risk of adverse birth outcomes. However, variation in the effect of neighborhood deprivation among diverse ethnic groups has not been studied.

METHODS

Using linked hospital discharge and birth data for 517,994 singleton live births in New York City from 1998 through 2002, we examined the association between neighborhood deprivation, preterm birth (PTB), and term low birthweight (TLBW) (>or=37 weeks and <2500g). Adjusted odds ratios (aORs) for PTB (<32 and 33-36 weeks) and TLBW were estimated using logistic regression.

RESULTS

The aOR for PTB of less than 32 weeks for the highest quartile of deprivation compared to the lowest was 1.24 (95% confidence limit [CL] = 1.13, 1.36), for PTB 33-36 weeks was 1.06 (95% CL = 1.01, 1.11), and for TLBW was 1.19 (95% CL = 1.11, 1.27). Measures of association varied by ethnicity; aORs of the greatest magnitude for PTB were found among Hispanic Caribbean women (PTB < 32 weeks: aOR = 1.63, 95% CL = 1.27, 2.10; PTB 33-36 weeks: aOR = 1.32, 95% CL = 1.02, 1.70), and for TLBW among African women (aOR = 1.47, 95% CL = 1.02, 2.13).

CONCLUSIONS

The mechanisms linking neighborhood deprivation to adverse birth outcomes may differ depending on individual ethnicity and/or cultural context and should be investigated in future research.

Neighbourhood characteristics, individual attributes and self-rated health among older Canadians

This study drew on three cycles of the Canadian Community Health Survey and the 2001 Census to examine between-neighbourhood variation in positive and negative self-rated health and the relative effect of individual and neighbourhood characteristics on self-rated health among Canadian adults aged > or = 65. Multilevel logistic regression results showed that there was modest, but significant between-neighbourhood variation in self-rated health. Neighbourhood factors including income, education, and percentage of people aged > or = 65, and visible minority accounted for about 50% and 30% of the neighbourhood variation in negative and positive self-rated health, respectively. Relative to neighbourhood-level characteristics, individual characteristics had a stronger effect on self-rated health with involvement in physical activity, alcohol consumption, sense of community belonging, income, and education being the most important. Although the findings suggest that neighbourhood effects on self-rated health are modest and that individual-level factors are relatively more important determinants of health, research concern for contextual influences on health should continue.

Immigrants' duration of residence and adverse birth outcomes: a population-based study

OBJECTIVE

This study aimed to examine preterm and small-for-gestational-age (SGA) births among immigrants, by duration of residence, and to compare them with the Canadian-born population.

DESIGN

Population-based cross-sectional study with retrospective assessment of immigration.

SETTING

Metropolitan areas of Ontario, Canada.

POPULATION

A total of 83 233 singleton newborns born to immigrant mothers and 314 237 newborns born to non-immigrant mothers.

METHODS

We linked a database of immigrants acquiring permanent residence in Ontario, Canada, in the period 1985-2000 with mother-infant hospital records (2002-2007). Duration of residence was measured as completed years from arrival to Canada to delivery/birth. Logistic regression models were used to estimate the effects of duration of residence with adjusted odds ratios and 95% confidence intervals. In analyses restricted to immigrants only, hierarchical models were used to account for the clustering of births into maternal countries of birth.

MAIN OUTCOME MEASURES

Preterm birth (PTB) and SGA birth.

RESULTS

Recent immigrants (<5 years) had a lower risk of PTB (4.7%) than non-immigrants (6.2%), but those with > or =15 years of stay were at higher risk (7.4%). Among immigrants, a 5-year increase in Canadian residence was associated with an increase in PTB (AOR 1.14, 95% CI 1.10-1.19), but not in SGA birth (AOR 0.99, 95% CI 0.96-1.02).

CONCLUSIONS

Time since migration was associated with increases in the risk of PTB, but was not associated with an increase in SGA births. Ignoring duration of residence may mask important disparities in preterm delivery between immigrants and non-immigrants, and between immigrant subgroups categorised by their duration of residence.

Age- and sex-related prevalence of diabetes mellitus among immigrants to Ontario, Canada

BACKGROUND

The majority of immigrants to Canada originate from the developing world, where the most rapid increase in prevalence of diabetes mellitus is occurring. We undertook a population-based study involving immigrants to Ontario, Canada, to evaluate the distribution of risk for diabetes in this population.

METHODS

We used linked administrative health and immigration records to calculate age-specific and age-adjusted prevalence rates among men and women aged 20 years or older in 2005. We compared rates among 1,122,771 immigrants to Ontario by country and region of birth to rates among long-term residents of the province. We used logistic regression to identify and quantify risk factors for diabetes in the immigrant population.

RESULTS

After controlling for age, immigration category, level of education, level of income and time since arrival, we found that, as compared with immigrants from western Europe and North America, risk for diabetes was elevated among immigrants from South Asia (odds ratio [OR] for men 4.01, 95% CI 3.82-4.21; OR for women 3.22, 95% CI 3.07-3.37), Latin America and the Caribbean (OR for men 2.18, 95% CI 2.08-2.30; OR for women 2.40, 95% CI: 2.29-2.52), and sub-Saharan Africa (OR for men 2.31, 95% CI 2.17-2.45; OR for women 1.83, 95% CI 1.72-1.95). Increased risk became evident at an early age (35-49 years) and was equally high or higher among women as compared with men. Lower socio-economic status and greater time living in Canada were also associated with increased risk for diabetes.

INTERPRETATION

Recent immigrants, particularly women and immigrants of South Asian and African origin, are at high risk for diabetes compared with long-term residents of Ontario. This risk becomes evident at an early age, suggesting that effective programs for prevention of diabetes should be developed and targeted to immigrants in all age groups.