Economic, physical, and political characteristics of neighborhood of residence and the risk of low birth weight.

Low birth weight remains an important public health problem in the U.S. Most research on low birth weight focuses on individual-level determinants of low birth weight such as health behaviors or use of prenatal care. We sought to determine how characteristics of residential neighborhood influenced low birth weight. We first present a theoretically based framework that describes the mechanisms by which neighborhoods can lead to adverse health outcomes. Our research question centered on whether neighborhood economic, physical and political characteristics directly and indirectly influenced the risk of low birth weight and whether neighborhood factors moderated the relation between individual-level risk factors and low birth weight. We used methods of multi-level statistical modelling to investigate our research question. Direct neighborhood level determinants of low birth weight included high crime (OR=2.49), low wealth (OR=5.50) and low level of political organization (2.54). Interactions and confounding between individual- and neighborhood-level characteristics were observed. When multi-level models accounted for neighborhood levels of wealth, the two-fold gap between African-American and White births was no longer significant. Methods of multi- level modelling facilitated testing of a model emphasizing environmental and social factors in determining poor health outcome. The application of such models also resulted in a better explanatory model for low birth weight. High rates of low birth weight births remain an important public health problem in the U.S., especially among impoverished communities. Most research on low birth weight, however, focuses on individual-level determinants of low birth weight such as maternal education, health behaviors including smoking during pregnancy, and quantity and quality of clinical care (1). Increasingly, public health researchers are recognizing that models of disease etiology that focus exclusively on individual characteristics (e.g., demographic, biologic or personality factors) are insufficient for explaining the complex set of factors that contribute to poor health (2, 3). For example, health behaviors and health outcomes of individuals are influenced by workplace and residential environments (2, 4-14). Studies on the influence of neighborhood residence on health outcomes often analyze individual- and community-level characteristics separately (15, 16). This has, in part, been due to (1) a lack of available data on the contexts of study subjects, (2) lack of easily accessible statistical methods and software for the analyses of complex multi-level data (17- 20), and (3) lack of appropriate theory that explicitly acknowledges the mechanisms by which contexts are related to health outcomes (17, 19, 22-24). We undertook the current study to contribute to theoretical development of neighborhood effects on health. In particular, we sought to build a conceptual framework describing the mechanisms by which residential characteristics influence health outcomes and low birth weight. We also were interested in answering two research questions concerning the relation between residential neighborhood risk of low birth weight. (1) Do neighborhood economic, physical and political characteristics directly and indirectly influence the risk of low birth weight? (2) Do neighborhood economic, physical and political characteristics moderate the relation between individual-level risk factors and low birth weight (LBW)

The joint influence of area income, income inequality, and immigrant density on adverse birth outcomes: a population-based study

<p>Abstract</p> <p>Background</p> <p>The association between area characteristics and birth outcomes is modified by race. Whether such associations vary according to social class indicators beyond race has not been assessed.</p> <p>Methods</p> <p>This study evaluated effect modification by maternal birthplace and education of the relationship between neighbourhood characteristics and birth outcomes of newborns from 1999–2003 in the province of Québec, Canada (N = 353,120 births). Areas (N = 143) were defined as administrative local health service delivery districts. Multi-level logistic regression was used to model the association between three area characteristics (median household income, immigrant density and income inequality) and the two outcomes preterm birth (PTB) and small-for-gestational age (SGA) birth. Effect modification by social class indicators was evaluated in analyses stratified according to maternal birthplace and education.</p> <p>Results</p> <p>Relative to the lowest tertile, high median household income was associated with SGA birth among Canadian-born mothers (odds ratio (OR) 1.13, 95% confidence interval (CI) 1.06, 1.20) and mothers with high school education or less (OR 1.13, 95% CI 1.02, 1.24). Associations between median household income and PTB were weaker. Relative to the highest tertile, low immigrant density was associated with a lower odds of PTB among foreign-born mothers (OR 0.79, 95% CI 0.63, 1.00) but a higher odds of PTB among Canadian-born mothers (OR 1.14, 95% CI 1.07, 1.21). Associations with income inequality were weak or absent.</p> <p>Conclusion</p> <p>The association between area factors and birth outcomes is modified by maternal birthplace and education. Studies have found that race interacts in a similar manner. Public health policies focussed on perinatal health must consider the interaction between individual and area characteristics.</p

Systematic Neighborhood Observations at High Spatial Resolution: Methodology and Assessment of Potential Benefits

There is a growing body of public health research documenting how characteristics of neighborhoods are associated with differences in the health status of residents. However, little is known about how the spatial resolution of neighborhood observational data or community audits affects the identification of neighborhood differences in health. We developed a systematic neighborhood observation instrument for collecting data at very high spatial resolution (we observe each parcel independently) and used it to collect data in a low-income minority neighborhood in Dallas, TX. In addition, we collected data on the health status of individuals residing in this neighborhood. We then assessed the inter-rater reliability of the instrument and compared the costs and benefits of using data at this high spatial resolution. Our instrument provides a reliable and cost-effect method for collecting neighborhood observational data at high spatial resolution, which then allows researchers to explore the impact of varying geographic aggregations. Furthermore, these data facilitate a demonstration of the predictive accuracy of self-reported health status. We find that ordered logit models of health status using observational data at different spatial resolution produce different results. This implies a need to analyze the variation in correlative relationships at different geographic resolutions when there is no solid theoretical rational for choosing a particular resolution. We argue that neighborhood data at high spatial resolution greatly facilitates the evaluation of alternative geographic specifications in studies of neighborhood and health

Area-level poverty and preterm birth risk: A population-based multilevel analysis

<p>Abstract</p> <p>Background</p> <p>Preterm birth is a complex disease with etiologic influences from a variety of social, environmental, hormonal, genetic, and other factors. The purpose of this study was to utilize a large population-based birth registry to estimate the independent effect of county-level poverty on preterm birth risk. To accomplish this, we used a multilevel logistic regression approach to account for multiple co-existent individual-level variables and county-level poverty rate.</p> <p>Methods</p> <p>Population-based study utilizing Missouri's birth certificate database (1989–1997). We conducted a multilevel logistic regression analysis to estimate the effect of county-level poverty on PTB risk. Of 634,994 births nested within 115 counties in Missouri, two levels were considered. Individual-level variables included demographics factors, prenatal care, health-related behavioral risk factors, and medical risk factors. The area-level variable included the percentage of the population within each county living below the poverty line (US census data, 1990). Counties were divided into quartiles of poverty; the first quartile (lowest rate of poverty) was the reference group.</p> <p>Results</p> <p>PTB < 35 weeks occurred in 24,490 pregnancies (3.9%). The rate of PTB < 35 weeks was 2.8% in counties within the lowest quartile of poverty and increased through the 4^thquartile (4.9%), p < 0.0001. High county-level poverty was significantly associated with PTB risk. PTB risk (< 35 weeks) was increased for women who resided in counties within the highest quartile of poverty, adjusted odds ratio (_adjOR) 1.18 (95% CI 1.03, 1.35), with a similar effect at earlier gestational ages (< 32 weeks), _adjOR 1.27 (95% CI 1.06, 1.52).</p> <p>Conclusion</p> <p>Women residing in socioeconomically deprived areas are at increased risk of preterm birth, above other underlying risk factors. Although the risk increase is modest, it affects a large number of pregnancies.</p

Association of various reproductive rights, domestic violence and marital rape with depression among Pakistani women

<p>Abstract</p> <p>Background</p> <p>Depression among women is common in developing countries. Gender inequality can contribute to women's risk for depression. Lack of reproductive and sexual rights is an important marker of gender inequality and women do not have the freedom to express their reproductive and sexual needs in many parts of the world. Therefore we designed this study to determine the association of depression with lack of various reproductive rights and domestic violence among married women in Karachi, Pakistan.</p> <p>Methods</p> <p>A case-control study with 152 cases and 152 controls, which included women 15-48 years, recruited from two teaching hospitals from 1^stJune 2007 through 31^stAugust 2007. The SRQ was administered to all subjects. A cut off score of 8 was used to confirm cases of depression diagnosed by physicians, and to exclude cases of depression from the controls. Self-administered questionnaire was used to assess the risk factors.</p> <p>Results</p> <p>61% of the cases and 43% of the controls were ever abused by spouse and the frequency of marital rape was 33% in cases and 13% in controls. After adjusting for the effects of other variables in the model, less than 18 years of age at marriage (OR 2.00; 95% CI = 1.07, 3.7), decision for marriage by parents (OR 3.51; 95% CI = 1.67, 7.37), abuse by in laws (OR 4.91; 95% CI = 2.66, 9.06), ≤ 3 hours per day spent with husband (OR 2.33; 95% CI = 1.34, 4.08), frequency of intercourse ≤ 2 times per week (OR 1.85; 95% CI = 1.06, 3.22) and marital rape (OR 3.03; 95% CI = 1.50, 6.11) were associated with depression among women.</p> <p>Conclusion</p> <p>In our study depression in married women was associated with younger age at marriage, lack of autonomy in marriage decisions, marital rape and domestic abuse by in-laws. Efforts should be directed towards creating awareness about the reproductive and sexual rights of women in Pakistan. Physicians should be trained to screen and identify women who may be at risk for psychological distress as a result of denial of reproductive rights so that they can support positive mental health outcomes through individual, family or marital counseling.</p

Realist synthesis : illustrating the method for implementation research

BackgroundRealist synthesis is an increasingly popular approach to the review and synthesis of evidence, which focuses on understanding the mechanisms by which an intervention works (or not). There are few published examples of realist synthesis. This paper therefore fills a gap by describing, in detail, the process used for a realist review and synthesis to answer the question \u27what interventions and strategies are effective in enabling evidence-informed healthcare?\u27 The strengths and challenges of conducting realist review are also considered. MethodsThe realist approach involves identifying underlying causal mechanisms and exploring how they work under what conditions. The stages of this review included: defining the scope of the review (concept mining and framework formulation); searching for and scrutinising the evidence; extracting and synthesising the evidence; and developing the narrative, including hypotheses. ResultsBased on key terms and concepts related to various interventions to promote evidenceinformed healthcare, we developed an outcome-focused theoretical framework. Questions were tailored for each of four theory/intervention areas within the theoretical framework and were used to guide development of a review and data extraction process. The search for literature within our first theory area, change agency, was executed and the screening procedure resulted in inclusion of 52 papers. Using the questions relevant to this theory area, data were extracted by one reviewer and validated by a second reviewer. Synthesis involved organisation of extracted data into evidence tables, theming and formulation of chains of inference, linking between the chains of inference, and hypothesis formulation. The narrative was developed around the hypotheses generated within the change agency theory area. ConclusionsRealist synthesis lends itself to the review of complex interventions because it accounts for context as well as outcomes in the process of systematically and transparently synthesising relevant literature. While realist synthesis demands flexible thinking and the ability to deal with complexity, the rewards include the potential for more pragmatic conclusions than alternative approaches to systematic reviewing. A separate publication will report the findings of the review. <br /

The joint influence of marital status, interpregnancy interval, and neighborhood on small for gestational age birth: a retrospective cohort study

<p>Abstract</p> <p>Background</p> <p>Interpregnancy interval (IPI), marital status, and neighborhood are independently associated with birth outcomes. The joint contribution of these exposures has not been evaluated. We tested for effect modification between IPI and marriage, controlling for neighborhood.</p> <p>Methods</p> <p>We analyzed a cohort of 98,330 live births in Montréal, Canada from 1997–2001 to assess IPI and marital status in relation to small for gestational age (SGA) birth. Births were categorized as subsequent-born with <it>short </it>(<12 months), <it>intermediate </it>(12–35 months), or <it>long </it>(36+ months) IPI, or as firstborn. The data had a 2-level hierarchical structure, with births nested in 49 neighborhoods. We used multilevel logistic regression to obtain adjusted effect estimates.</p> <p>Results</p> <p>Marital status modified the association between IPI and SGA birth. Being unmarried relative to married was associated with SGA birth for all IPI categories, particularly for subsequent births with <it>short </it>(odds ratio [OR] 1.60, 95% confidence interval [CI] 1.31–1.95) and <it>intermediate </it>(OR 1.48, 95% CI 1.26–1.74) IPIs. Subsequent births had a lower likelihood of SGA birth than firstborns. <it>Intermediate </it>IPIs were more protective for married (OR 0.50, 95% CI 0.47–0.54) than unmarried mothers (OR 0.65, 95% CI 0.56–0.76).</p> <p>Conclusion</p> <p>Being unmarried increases the likelihood of SGA birth as the IPI shortens, and the protective effect of <it>intermediate </it>IPIs is reduced in unmarried mothers. Marital status should be considered in recommending particular IPIs as an intervention to improve birth outcomes.</p

Socioeconomic status and non-fatal injuries among Canadian adolescents: variations across SES and injury measures

BACKGROUND: While research to date has consistently demonstrated that socioeconomic status (SES) is inversely associated with injury mortality in both children and adults, findings have been less consistent for non-fatal injuries. The literature addressing SES and injury morbidity among adolescents has been particularly inconclusive. To explore potential explanations for these discrepant research findings, this study uniquely compared the relationship across different measures of SES and different causes of injury (recreation versus non-recreation injuries) within a sample of Canadian adolescents. METHODS: The sample included adolescent participants (aged 12 to 19 years) in the Canadian 1996–1997 cross-sectional National Population Health Survey (n = 6967). Five SES measures (household income, two neighbourhood-level proxy measures, two parental indicators) were examined in relation to three injury outcomes (total, recreation, and non-recreation injuries) using multivariable logistic regression. RESULTS: Among males, a clear relationship with injury was observed only for a parental SES index, which was positively associated with total and recreation injuries (odds ratios for the highest versus lowest SES category of 1.9 for total and 2.5 for recreation injuries). Among females, there was some evidence of a positive relationship between SES and injuries, particularly for a neighbourhood-level education measure with total and recreation injuries (odds ratios of 1.7 for total and 2.0 for recreation injuries). CONCLUSION: The results suggest that differences related to the measures of SES chosen and the causes of injury under study may both contribute to discrepancies in past research on SES and non-fatal injuries among adolescents. To clarify the potential SES-injury relationship among youth, the findings emphasize a need for a greater understanding of the meaning and relevance of different SES measures for adolescents, and for an exploration of the pathways through which SES may be related to injury risk

Ambient air pollution exposure and full-term birth weight in California

<p>Abstract</p> <p>Background</p> <p>Studies have identified relationships between air pollution and birth weight, but have been inconsistent in identifying individual pollutants inversely associated with birth weight or elucidating susceptibility of the fetus by trimester of exposure. We examined effects of prenatal ambient pollution exposure on average birth weight and risk of low birth weight in full-term births.</p> <p>Methods</p> <p>We estimated average ambient air pollutant concentrations throughout pregnancy in the neighborhoods of women who delivered term singleton live births between 1996 and 2006 in California. We adjusted effect estimates of air pollutants on birth weight for infant characteristics, maternal characteristics, neighborhood socioeconomic factors, and year and season of birth.</p> <p>Results</p> <p>3,545,177 singleton births had monitoring for at least one air pollutant within a 10 km radius of the tract or ZIP Code of the mother's residence. In multivariate models, pollutants were associated with decreased birth weight; -5.4 grams (95% confidence interval -6.8 g, -4.1 g) per ppm carbon monoxide, -9.0 g (-9.6 g, -8.4 g) per pphm nitrogen dioxide, -5.7 g (-6.6 g, -4.9 g) per pphm ozone, -7.7 g (-7.9 g, -6.6 g) per 10 <it>μ</it>g/m³particulate matter under 10 μm, -12.8 g (-14.3 g, -11.3 g) per 10 <it>μ</it>g/m³particulate matter under 2.5 μm, and -9.3 g (-10.7 g, -7.9 g) per 10 <it>μ</it>g/m³of coarse particulate matter. With the exception of carbon monoxide, estimates were largely unchanged after controlling for co-pollutants. Effect estimates for the third trimester largely reflect the results seen from full pregnancy exposure estimates; greater variation in results is seen in effect estimates specific to the first and second trimesters.</p> <p>Conclusions</p> <p>This study indicates that maternal exposure to ambient air pollution results in modestly lower infant birth weight. A small decline in birth weight is unlikely to have clinical relevance for individual infants, and there is debate about whether a small shift in the population distribution of birth weight has broader health implications. However, the ubiquity of air pollution exposures, the responsiveness of pollutant levels to regulation, and the fact that the highest pollution levels in California are lower than those regularly experienced in other countries suggest that precautionary efforts to reduce pollutants may be beneficial for infant health from a population perspective.</p