A marginal structural modeling strategy investigating short and long-term exposure to neighborhood poverty on BMI among U.S. black and white adults

Impact of being underweight before pregnancy on preterm birth by race/ethnicity and insurance status in California: an analysis of birth records

BACKGROUND

The US still has a high burden of preterm birth (PTB), with important disparities by race/ethnicity and poverty status. There is a large body of literature looking at the impact of pre-pregnancy obesity on PTB, but fewer studies have explored the association between underweight status on PTB, especially with a lens toward health disparities. Furthermore, little is known about how weight, specifically pre-pregnancy underweight status, and socio-economic-demographic factors such as race/ethnicity and insurance status, interact with each other to contribute to risks of PTB.

OBJECTIVES

The objective of this study was to measure the association between pre-pregnancy underweight and PTB and small for gestational age (SGA) among a large sample of births in the US. Our secondary objective was to see if underweight status and two markers of health disparities - race/ethnicity and insurance status (public vs. other) - on PTB.

STUDY DESIGN

We used data from all births in California from 2011 to 2017, which resulted in 3,070,241 singleton births with linked hospital discharge records. We ran regression models to estimate the relative risk of PTB by underweight status, by race/ethnicity, and by poverty (Medi-cal status). We then looked at the interaction between underweight status and race/ethnicity and underweight and poverty on PTB.

RESULTS

Black and Asian women were more likely to be underweight (aRR = 1.0, 95% CI: 1.01, 1.1 and aRR = 1.4, 95% CI: 1.4, 1.5, respectively), and Latina women were less likely to be underweight (aRR = 0.7, 95% CI: 0.7, 0.7). Being underweight was associated with increased odds of PTB (aRR = 1.3, 95% CI 1.3-1.3) and, after controlling for underweight, all nonwhite race/ethnic groups had increased odds of PTB compared to white women. In interaction models, the combined effect of being both underweight and Black, Indigenous and People of Color (BIPOC) statistically significantly reduced the relative risk of PTB (aRR = 0.9, 95% CI: 0.8, 0.9) and SGA (aRR = 1.0, 95% CI: 0.9, 1.0). The combined effect of being both underweight and on public insurance increased the relative risk of PTB (aRR = 1.1, 95% CI: 1.1, 1.2) but there was no additional effect of being both underweight and on public insurance on SGA (aRR = 1.0, 95% CI: 1.0, 1.0).

CONCLUSIONS

We confirm and build upon previous findings that being underweight preconception is associated with increased risk of PTB and SGA - a fact often overlooked in the focus on overweight and adverse birth outcomes. Additionally, our findings suggest that the effect of being underweight on PTB and SGA differs by race/ethnicity and by insurance status, emphasizing that other factors related to inequities in access to health care and poverty are contributing to disparities in PTB.

Longitudinal Exposure to Neighborhood Concentrated Poverty Contributes to Differences in Adiposity in Midlife Women

Background: Neighborhood poverty is associated with adiposity in women, though longitudinal designs, annually collected residential histories, objectively collected anthropometric measures, and geographically diverse samples of midlife women remain limited. Objective: To investigate whether longitudinal exposure to neighborhood concentrated poverty is associated with differences in body mass index (BMI) and waist circumference (WC) among 2,328 midlife women (age 42-52 years at baseline) from 6 U.S. cities enrolled in the Study of Women's Health Across the Nation (SWAN) from 1996 to 2007. Methods: Residential addresses and adiposity measures were collected at approximately annual intervals from the baseline visit through a 10-year follow-up. We used census poverty data and local spatial statistics to identify hot-spots of high concentrated poverty areas and cold-spots of low concentrated poverty located within each SWAN site region, and used linear mixed-effect models to estimate percentage differences (95% confidence interval [CI]) in average BMI and WC levels between neighborhood concentrated poverty categories. Results: After adjusting for individual-level sociodemographics, health-related factors, and residential mobility, compared to residents of moderate concentrated poverty communities, women living in site-specific hot-spots of high concentrated poverty had 1.5% higher (95% CI: 0.6, 2.3) BMI and 1.3% higher (95% CI: 0.5, 2.0) WC levels, whereas women living in cold-spots of low concentrated poverty had 0.7% lower (95% CI: -1.2, -0.1) BMI and 0.3% lower (95% CI: -0.8, 0.2) WC. Site-stratified results remained in largely similar directions to overall estimates, despite wide CIs and small sample sizes. Conclusions: Longitudinal exposure to neighborhood concentrated poverty is associated with slightly higher BMI and WC among women across midlife.

Neighborhood deprivation and obesity: Sex-specific effects of cross-sectional, cumulative and residential trajectory indicators

Obesity is a long-term health issue that is becoming increasingly prevalent. Very few studies have considered the life course effects of neighborhood characteristics on obesity. In a sample of 35,856 adult participants (representative of the population of the Province of Quebec in Canada), we measured the association between neighborhood deprivation and obesity using logistic modelling on indicators of cross-sectional neighborhood deprivation, cumulative neighborhood deprivation and trajectories of neighborhood deprivation. For cross-sectional exposure, we found that females in our sample had higher odds of being affected by obesity when living in high-deprivation (OR 1.73, CI 1.41-2.13) or medium-deprivation neighborhoods (OR 1.27, CI 1.07-1.51) compared to females living in low-deprivation neighborhoods. Males also had higher odds of being affected by obesity when living in medium or high deprivation. For cumulative exposure to neighborhood deprivation, only females in the second highest category for longitudinal exposure to deprived neighborhoods had significantly higher odds of living with obesity (OR 1.89 CI 1.12-3.19) compared to females in the low cumulative exposure category. Using sequence analysis to determine neighborhood deprivation trajectories for up to 17 years, we found that females with a Deprived upward (OR 1.75 CI 1.10-2.78), an Average downward (OR 1.75 CI 1.08-2.84) or a Deprived trajectory (OR 1.81 CI 1.45-2.86) had higher odds of living with obesity compared to the Privileged trajectory. For males, there were no significant associations. Using trajectory indicators was beneficial to our analyses because this method shows that not only are individuals in low socioeconomic status neighborhoods at the end of their trajectory more susceptible to living with obesity, but so are those exposed to neighborhood deprivation at the beginning of their trajectory. These results could help to more precisely identify individuals at higher risk of developing obesity-related health issues.

Examining the impacts of neighborhood poverty on bodyweight across the BMI distribution: a quantile and MSM modeling approach

PURPOSE

Given that the relationships between higher BMI and adverse health outcomes are nonconstant and most pronounced at either ends of the BMI distribution, we assess the association between neighborhood poverty and BMI at multiple points along the BMI distribution.

METHODS

Using data from the 1999 to 2015 Panel Study of Income Dynamics of Black and White adults in the United States, we estimate quantile regression models while jointly applying a marginal structural modeling approach to account for time-varying individual-level factors that may be simultaneously mediators as well as confounders.

RESULTS

Neighborhood poverty was not found to be associated with bodyweight at any point along the BMI distribution for Black or White males. However, high neighborhood poverty, compared to low neighborhood poverty, predicted increases in bodyweight for Black females at the lower end of the BMI distribution and for White females at the higher end of the BMI distribution. No association was found between neighborhood poverty and BMI at the mean.

CONCLUSIONS

Results identify the most vulnerable subgroups, suggesting that White females at the higher end of the BMI distribution as well as Black females at the lower end of the BMI distribution are particularly sensitive to obesogenic environments.

Impact of race on outcomes in intermediate-risk acute myeloid leukemia

PURPOSE

Racial disparities in acute myeloid leukemia (AML) have been reported but the relative contribution of disease versus patient-specific factors including comorbidities and access to care is unclear.

METHODS

We conducted a retrospective analysis of patient characteristics, treatment patterns and outcomes in a racially diverse patient cohort controlling for cytogenetic risk group. Patients were classified into four groups: non-Hispanic White (NHW), non-Hispanic Black (NHB), Hispanic and Other.

RESULTS

We evaluated 106 patients from 84 zipcodes incorporating demographics, clinicopathologic features, treatment patterns and outcomes. We identified significant differences in BMI and geographic poverty based on ethnoracial group, while prognostic mutations in NPM1 and FLT3 did not differ significantly. Utilization of intensive chemotherapy and transplant rate did not differ by ethnoracial group. However, there was a significantly higher use of alternate donor transplants in minority populations. There was a notably increased rate of clinical trial enrollment in NHW patients compared to other groups. In log-rank analysis, NHW patients had increased overall survival (OS) compared to NHB, Hispanic and Other patients (31.6 months vs. 16.7 months vs. 14.3 months, vs 18.1 months, p = 0.021). In bivariate analysis, overall survival was negatively influenced by advanced age and race. Obesity and zip code poverty levels approached statistical significance in predicting OS. In multivariate analysis, the only factors independently influencing OS were race and allogeneic stem cell transplant.

CONCLUSION

These results suggest that race impacts survival in intermediate-risk AML, highlighting the need to dissect biologic and nonbiologic factors that contribute to this disparity.

Neighbourhood effects on obesity: scoping review of time-varying outcomes and exposures in longitudinal designs

CONTEXT AND OBJECTIVES

Neighbourhood effect research on obesity took off in the early 2000s and was composed of mostly cross-sectional observational studies interested in various characteristics of the built environment and the socioeconomic environment. To limit biases related to self-selection and life course exposures, many researchers apply longitudinal designs in their studies. Until now, no review has specifically and exclusively examined longitudinal studies and the specific designs of these studies. In this review, we intend to answer the following research question: how are the temporal measurements of contextual exposure and obesity outcomes integrated into longitudinal studies that explore how neighbourhood-level built and socioeconomic environments impact adult obesity?

DESIGN

A systematic search strategy was designed to address the research question. The search was performed in Embase, Web of Science and PubMed, targeting scientific papers published before 1 January 2018. The eligible studies reported results on adults, included exposure that was limited to neighbourhood characteristics at the submunicipal level, included an outcome limited to obesity proxies, and reported a design with at least two exposure measurements or two outcome measurements.

RESULTS

This scoping review identified 66 studies that fit the eligibility criteria. A wide variety of neighbourhood characteristics were also measured, making it difficult to draw general conclusions about associations between neighbourhood exposure and obesity. We applied a typology that classified studies by whether exposure and outcome were measured as varying or fixed. Using this typology, we found that 32 studies reported both neighbourhood exposure and obesity outcomes that were varying in time; 28 reported varying outcomes but fixed exposures; and 6 had fixed outcomes and varying exposures.

CONCLUSION

Our typology illustrates the variety of longitudinal designs that were used in the selected studies. In the light of our results, we make recommendations on how to better report longitudinal designs and facilitate comparisons between studies.

Neighborhood disadvantage across the transition from adolescence to adulthood and risk of metabolic syndrome

This study investigates the association between neighborhood disadvantage from adolescence to young adulthood and metabolic syndrome using a life course epidemiology framework. Data from the United States-based National Longitudinal Study of Adolescent to Adult Health (n = 9500) and a structural equation modeling approach were used to test neighborhood disadvantage across adolescence, emerging adulthood, and young adulthood in relation to metabolic syndrome. Adolescent neighborhood disadvantage was directly associated with metabolic syndrome in young adulthood. Evidence supporting an indirect association between adolescent neighborhood disadvantage and adult metabolic syndrome was not supported. Efforts to improve cardiometabolic health may benefit from strategies earlier in life.

Neighborhood Social Environment and Cardiovascular Disease Risk

Purpose of review

Limited physical activity (PA) and obesity are two primary risk factors for cardiovascular disease (CVD). Within a socio-ecological framework, neighborhood social environment may play a key role in influencing PA and obesity. However, the mechanisms underlying this relationship remain ambiguous. Our goals in this review are: (1) to summarize findings from the recent studies on neighborhood social environment in relation to PA and obesity as CVD risk factors, and (2) to briefly describe several innovative approaches to assessing neighborhood social environment.

Recent findings

Almost all recent studies assessed neighborhood social environment around residential areas. There were consistent associations between neighborhood social environment and PA and obesity, with some exceptions (indicating null associations or paradoxical associations). However, a focus on residential social environment may limit results because these studies did not account for any exposures occurring away from individuals' homes. Additionally, the majority of studies utilized a cross-sectional design, which limits our ability to make inferences regarding the causality of the association between social environment and PA or obesity as CV risk factors.

Summary

The majority of the studies on neighborhood social environment characterized factors around residential areas and assessed participant activity via self-reported surveys. Future research should leverage tools to account for the spatial mismatch between environmental exposures and outcomes by using global positioning systems, ecological momentary assessments, virtual neighborhood audits, and simulation modeling. These approaches can overcome major limitations by tracking individuals' daily activity and real-time perceptions of neighborhood social environments linked to CVD events.

Mental health status and dietary intake among California adults: a population-based survey

California Health Interview Survey (2005-2015) data were used to examine the association between dietary intake frequencies and mental health - Kessler-6 scores categorised as no/low (NLPD), moderate (MPD) or serious psychological distress (SPD). The 245,891 surveys represented 27.7 million adults annually, with 13.2% having MPD and 3.7% SPD. Survey-adjusted regression adjusting for gender, age, race, education, poverty, marital status, BMI, geography and year found MPD and SPD associated with lower consumption of fruits (adjusted odds ratio 0.79 and 0.65, respectively), vegetables (AOR 0.81 and 0.68), and increased consumption of French fries (AOR 1.24, 1.30), fast food (AOR 1.32, 1.27), soda (AOR 1.23, 1.26) and variance-adjusted daily teaspoons of sugar (coefficients 3.05, 4.21), all p-values less than 0.001. In this large population-based sample, moderate and SPD were independently associated with unhealthy diet. Targeted public health interventions could focus on young adults and those with less than 12 years of education.

Biological embedding of neighborhood disadvantage and collective efficacy: Influences on chronic illness via accelerated cardiometabolic age

The present study extends prior research on the link between neighborhood disadvantage and chronic illness by testing an integrated model in which neighborhood characteristics exert effects on health conditions through accelerated cardiometabolic aging. Hypotheses were tested using a sample of 408 African Americans from the Family and Community Health Study. Using four waves of data spanning young adulthood (ages 18-29), we first found durable effects of neighborhood disadvantage on accelerated cardiometabolic aging and chronic illness. Then, we used marginal structural modeling to adjust for potential neighborhood selection effects. As expected, accelerated cardiometabolic aging was the biopsychosocial mechanism that mediated much of the association between neighborhood disadvantage and chronic illness. This finding provides additional support for the view that neighborhood disadvantage can influence morbidity and mortality by creating social contexts that becomes biologically embedded. Perceived neighborhood collective efficacy served to buffer the relationship between neighborhood disadvantage and biological aging, identifying neighborhood-level resilience factor. Overall, our results indicate that neighborhood context serves as a fundamental cause of weathering and accelerated biological aging. Residing in a disadvantaged neighborhood increases biological wear and tear that ultimately leads to onset of chronic illness, but access to perceived collective efficacy buffers the impact of these neighborhood effects. From an intervention standpoint, identifying such an integrated model may help inform future health-promoting interventions.

Self-Reported vs. Measured Height, Weight, and BMI in Young Adults

Self-reported height and weight, if accurate, provide a simple and economical method to track changes in body weight over time. Literature suggests adults tend to under-report their own weight and that the gap between self-reported weight and actual weight increases with obesity. This study investigates the extent of discrepancy in self-reported height, weight, and subsequent Body Mass Index (BMI) versus actual measurements in young adults. Physically measured and self-reported height and weight were taken from 1562 students. Male students marginally overestimated height, while females were closer to target. Males, on average, closely self-reported weight. Self-reported anthropometrics remained statistically correlated to actual measures in both sexes. Categorical variables of calculated BMI from both self-reported and actual height and weight resulted in significant agreement for both sexes. Researcher measured BMI (via anthropometric height and weight) and sex were both found to have association with self-reported weight while only sex was related to height difference. Regression examining weight difference and BMI was significant, specifically with a negative slope indicating increased BMI led to increased underestimation of weight in both sexes. This study suggests self-reported anthropometric measurements in young adults can be used to calculate BMI for weight classification purposes. Further investigation is needed to better assess self-reported vs measured height and weight discrepancies across populations.

Neighbourhood disadvantage, geographic remoteness and body mass index among immigrants to Australia: A national cohort study 2006-2014

Obesity is socioeconomically, geographically and ethnically patterned. Understanding these elements of disadvantage is vital in understanding population obesity trends and the development of effective and equitable interventions. This study examined the relationship between neighbourhood socioeconomic disadvantage and geographic remoteness with prospective trends in mean body mass index (BMI) among immigrants to Australia. Longitudinal data (2006–2014) from a national panel survey of Australian adults was divided into an immigrant-only sample (n = 4,293, 52.6% women and 19,404 person-year observations). The data were analysed using multi-level random effects linear regression modelling that controlled for individual socioeconomic and demographic factors. Male immigrants living in the most disadvantaged neighbourhoods had significantly higher mean BMI compared with those living in the least disadvantaged. Over time, mean BMI increased for all groups except for men living in the least disadvantaged neighbourhoods, for whom mean BMI remained almost static (0.1 kg/m² increase from 2006 to 2014), effectively widening neighbourhood inequalities. Among women, mean BMI was also significantly higher in the most compared with the least, disadvantaged neighbourhoods (β = 2.08 kg/m²; 95%CI: 1.48, 2.68). Neighbourhood inequalities were maintained over time as mean BMI increased for all groups at a similar rate. Male and female immigrants residing in outer regional areas had significantly higher mean BMI compared with those living in major cities; however, differences were attenuated and no longer significant following adjustment for ethnicity, individual socioeconomic position and neighbourhood disadvantage. Over time, mean BMI increased in all male and female groups with no differences based on geographic remoteness. Obesity prevention policy targeted at immigrant cohorts needs to include area-level interventions that address inequalities in BMI arising from neighbourhood disadvantage, and be inclusive of immigrants living outside Australia’s major cities.