Mortality Associated With Proportionality of Secondary Mitral Regurgitation After Transcatheter Mitral Valve Repair: North American Mitraclip for Functional Mitral Regurgitation Registry.

The association, if any, between the effective regurgitant orifice area (EROA) to left ventricular end-diastolic volume (LVEDV) ratio and 1-year mortality is controversial in patients who undergo mitral transcatheter edge-to-edge repair (m-TEER) with the MitraClip system (Abbott Vascular, Santa Clara, CA). This study's objective was to determine the association between EROA/LVEDV and 1-year mortality in patients who undergo m-TEER with MitraClip. In patients with severe secondary (functional) mitral regurgitation (MR), we analyzed registry data from 11 centers using generalized linear models with the generalized estimating equations approach. We studied 525 patients with secondary MR who underwent m-TEER. Most patients were male (63%) and were New York Heart Association class III (61%) or IV (21%). Mitral regurgitation was caused by ischemic cardiomyopathy in 51% of patients. EROA/LVEDV values varied widely, with median = 0.19 mm2/ml, interquartile range [0.12,0.28] mm2/ml, and 187 patients (36%) had values <0.15 mm2/ml. Postprocedural mitral regurgitation severity was substantially alleviated, being 1+ or less in 74%, 2+ in 20%, 3+ in 4%, and 4+ in 2%; 1-year mortality was 22%. After adjustment for confounders, the logarithmic transformation (Ln) of EROA/LVEDV was associated with 1-year mortality (odds ratio 0.600, 95% confidence interval 0.386 to 0.933, p = 0.023). A higher Society of Thoracic Surgeons risk score was also associated with increased mortality. In conclusion, lower values of Ln(EROA/LVEDV) were associated with increased 1-year mortality in this multicenter registry. The slope of the association is steep at low values but gradually flattens as Ln(EROA/LVEDV) increases.

Angiotensin II for the Treatment of Refractory Shock: A Matched Analysis.

OBJECTIVES: To determine if angiotensin II is associated with improved outcomes as measured by 30- and 90-day mortality as well as other secondary outcomes such as organ dysfunction and adverse events. DESIGN: Retrospective, matched analysis of patients receiving angiotensin II compared with both historical and concurrent controls receiving equivalent doses of nonangiotensin II vasopressors. SETTING: Multiple ICUs in a large, university-based hospital. PATIENTS: Eight hundred thirteen adult patients with shock admitted to an ICU and requiring vasopressor support. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Angiotensin II use had no association with the primary outcome of 30-day mortality (60% vs 56%; p = 0.292). The secondary outcome of 90-day mortality was also similar (65% vs 63%; p = 0.440) as were changes in Sequential Organ Failure Assessment scores over a 5-day monitoring period after enrollment. Angiotensin II was not associated with increased rates of kidney replacement therapy (odds ratio [OR], 1.39; 95% CI, 0.88-2.19; p = 0.158) or receipt of mechanical ventilation (OR, 1.50; 95% CI, 0.41-5.51; p = 0.539) after enrollment, and the rate of thrombotic events was similar between angiotensin II and control patients (OR, 1.02; 95% CI, 0.71-1.48; p = 0.912). CONCLUSIONS: In patients with severe shock, angiotensin II was not associated with improved mortality or organ dysfunction and was not associated with an increased rate of adverse events.

Patient-, Clinician-, and Institution-level Variation in Inotrope Use for Cardiac Surgery: A Multicenter Observational Analysis.

BACKGROUND: Conflicting evidence exists regarding the risks and benefits of inotropic therapies during cardiac surgery, and the extent of variation in clinical practice remains understudied. Therefore, the authors sought to quantify patient-, anesthesiologist-, and hospital-related contributions to variation in inotrope use. METHODS: In this observational study, nonemergent adult cardiac surgeries using cardiopulmonary bypass were reviewed across a multicenter cohort of academic and community hospitals from 2014 to 2019. Patients who were moribund, receiving mechanical circulatory support, or receiving preoperative or home inotropes were excluded. The primary outcome was an inotrope infusion (epinephrine, dobutamine, milrinone, dopamine) administered for greater than 60 consecutive min intraoperatively or ongoing upon transport from the operating room. Institution-, clinician-, and patient-level variance components were studied. RESULTS: Among 51,085 cases across 611 attending anesthesiologists and 29 hospitals, 27,033 (52.9%) cases received at least one intraoperative inotrope, including 21,796 (42.7%) epinephrine, 6,360 (12.4%) milrinone, 2,000 (3.9%) dobutamine, and 602 (1.2%) dopamine (non-mutually exclusive). Variation in inotrope use was 22.6% attributable to the institution, 6.8% attributable to the primary attending anesthesiologist, and 70.6% attributable to the patient. The adjusted median odds ratio for the same patient receiving inotropes was 1.73 between 2 randomly selected clinicians and 3.55 between 2 randomly selected institutions. Factors most strongly associated with increased likelihood of inotrope use were institutional medical school affiliation (adjusted odds ratio, 6.2; 95% CI, 1.39 to 27.8), heart failure (adjusted odds ratio, 2.60; 95% CI, 2.46 to 2.76), pulmonary circulation disorder (adjusted odds ratio, 1.72; 95% CI, 1.58 to 1.87), loop diuretic home medication (adjusted odds ratio, 1.55; 95% CI, 1.42 to 1.69), Black race (adjusted odds ratio, 1.49; 95% CI, 1.32 to 1.68), and digoxin home medication (adjusted odds ratio, 1.48; 95% CI, 1.18 to 1.86). CONCLUSIONS: Variation in inotrope use during cardiac surgery is attributable to the institution and to the clinician, in addition to the patient. Variation across institutions and clinicians suggests a need for future quantitative and qualitative research to understand variation in inotrope use affecting outcomes and develop evidence-based, patient-centered inotrope therapies.

Identification of intraoperative management strategies that have a differential effect on patients with reduced left ventricular ejection fraction: a retrospective cohort study.

BACKGROUND: There are few data to guide the intraoperative management of patients with reduced left ventricular ejection fraction (LVEF). This study aimed to describe how patients with reduced LVEF are managed differently and to identify and treatments had a different risk profile in this population. METHODS: We performed a retrospective cohort study of adult patients who underwent general anesthesia for non-cardiac surgery. The effect of anesthesia medications and fluid balance was compared between those with and without a reduced preoperative LVEF. The primary outcome was a composite of acute kidney injury, myocardial injury, pulmonary complications, and 30-day mortality. Multivariable logistic regression was used to adjust for confounders. Treatments that affected patients with reduced LVEF differently were defined as those associated with the primary outcome that also had a significant interaction with LVEF. RESULTS: A total of 9420 patients were included. Patients with reduced LVEF tended to have a less positive fluid balance. Etomidate, calcium, and phenylephrine were use more frequently, while propofol and remifentanil were used less frequently. Remifentanil affected patients with reduced LVEF differently than those without (interaction term OR 2.71, 95% CI 1.30-5.68, p = 0.008). While the use of remifentanil was associated with fewer complications in patients with normal systolic function (OR 0.54, 95% CI 0.42-0.68, p < 0.001), it was associated with an increase in complications in patients with reduced LVEF (OR = 3.13, 95% CI 3.06-5.98, p = 0.026). CONCLUSIONS: Patients with a reduced preoperative LVEF are treated differently than those with a normal LVEF when undergoing non-cardiac surgery. An association was found between the use of remifentanil and an increase in postoperative adverse events that was unique to this population. Future research is needed to determine if this relationship is secondary to the medication itself or reflects a difference in how remifentanil is used in patients with reduced LVEF.

Independent and joint contributions of economic, social and physical environmental characteristics to mortality in the Detroit Metropolitan Area: A study of cumulative effects and pathways.

OBJECTIVE: Previous studies have demonstrated associations between race-based residential segregation, neighborhood socioeconomic and physical environmental characteristics, and mortality. Relatively few studies have examined independent and joint effects of these multiple neighborhood characteristics and mortality, including potential mediating pathways. In this study we examine the extent to which associations between race-based residential segregation and all-cause mortality may be explained by multiple socioeconomic indicators and exposure to air pollutants. METHODS: Drawing on data from multiple sources, we assessed bivariate associations between race-based residential segregation (operationalized as percent non-Hispanic Black), education (percent with graduate equivalency degree), poverty (percent below poverty), income inequality (GINI coefficient) and air pollution (ambient PM2.5) and age adjusted all-cause, all race mortality (henceforth all cause mortality) at the census tract level in the Detroit Metropolitan Area. We used inequality curves to assess the (in)equitable distribution of economic and environmental characteristics by census tract racial composition. Finally, we used generalized estimating equations (GEE) to examine independent and joint associations among percent NHB, education, income inequality, and air pollution to all-cause mortality, and test for mediating effects. RESULTS: Bivariate associations between racial composition, education, poverty, income inequality, PM2.5 and all-cause mortality were statistically significant. Census tracts with higher concentrations of NHB residents had significantly lower educational attainment, higher poverty, and greater exposure to PM2.5. In multivariate models, education, income inequality and PM2.5 fully attenuated associations between racial composition and all-cause mortality. CONCLUSIONS: Results are consistent with the hypothesis that race-based residential segregation is associated with heightened all-cause mortality, and that those effects are mediated by education, income inequality, and exposure to air pollution at the census tract level. Public health and cross-sector interventions to eliminate race-based residential segregation or to eliminate the maldistribution of educational and economic resources, and environmental exposures, across census tracts could substantially reduce regional inequities in all-cause mortality.

MI-Environment: Geospatial patterns and inequality of relative heat stress vulnerability in Michigan.

Heat stress causes morbidity and mortality and is increasing with climate change. Heat stress can pose particular challenges in northern regions not well adapted to heat. To assist decision makers, we identified the relative vulnerability of census tracts within Michigan to factors that increase exposure to heat stress or reflect susceptibilities in the population based on a California heat vulnerability index. In the MI-Environment assessment, we used a Geographic Information System (GIS) to combine future ensemble climate model projections to create a total of 9 geospatial and demographic variables. As part of a broader planned cumulative environmental exposure assessment, the statewide heat vulnerability index (HVI) maps display the location and relative magnitude of exposure on three metrics: built environment (Place), future expected long-term temperature averages (Temperature), and population susceptibility (People). We observed varied and distinct patterns for each of the three component indices. We assessed how equitably those exposures are distributed by racial and socioeconomic factors. This analysis showed that each of the component indices and the aggregate HVI are disproportionately distributed along racial and socioeconomic lines in Michigan. Census tracts with higher percentages of people of color had larger exposure to HVI factors with a deviation from equity of -0.115 [95% CI -0.108, -0.122]. Similarly, for census tracts with higher percentage of people experiencing poverty, the deviation from equity was -0.101 [95% CI -0.094, -0.107]. The MI-Environment visualization tool can help communities prepare for climate change and resolve inequities by identifying census tracts with the most vulnerable residents and highest potential exposures.

Social relationships, neighbourhood poverty and cumulative biological risk: findings from a multi-racial US urban community.

Prior research has established associations between neighbourhood poverty and cumulative biological risk (CBR). CBR is conceptualized as indicative of the effects of stress on biological functioning, and is linked with increased morbidity and mortality. Studies suggest that supportive social relationships may be health protective, and may erode under conditions of poverty. This study examines whether social relationships are inversely associated with CBR and whether associations between neighbourhood poverty and CBR are mediated through social relationships. Data were from a stratified probability sample community survey (n=919) of residents of Detroit, Michigan, USA (2002-2003) and from the 2000 US Census. The outcome variable, CBR, included anthropometric and clinical measures. Independent variables included four indicators of social relationships: social support, neighbourhood satisfaction, social cohesion and neighbourhood participation. Multilevel models were used to test both research questions, with neighbourhood poverty and social relationships included at the block group level, and social relationships also included at the individual level, to disentangle individual from neighbourhood effects. Findings suggest some associations between social relationships and CBR after accounting for neighbourhood poverty and individual characteristics. In models that accounted for all indicators of social relationships, individual-level social support was associated with greater CBR (ß=0.12, p=0.04), while neighbourhood-level social support was marginally significantly protective of CBR (within-neighbourhood: ß=-0.36, p=0.06; between-neighbourhood: ß=-0.24, p=0.06). In contrast, individual-level neighbourhood satisfaction was protective of CBR (ß=-0.10, p=0.02), with no within-neighbourhood (ß=0.06, p=0.54) or between-neighbourhood association (ß=-0.04, p=0.38). Results indicate no significant association between either social cohesion or neighbourhood participation and CBR. Associations between neighbourhood poverty and CBR were not mediated by social relationships. These findings suggest that neighbourhood-level social support and individual-level neighbourhood satisfaction may be health protective and that neighbourhood poverty, social support and neighbourhood satisfaction are associated with CBR through independent pathways.

Impact of community respiratory viral infections in urban children with asthma.

BACKGROUND: Upper respiratory tract viral infections cause asthma exacerbations in children. However, the impact of natural colds on children with asthma in the community, particularly in the high-risk urban environment, is less well defined. OBJECTIVE: We hypothesized that children with high-symptom upper respiratory viral infections have reduced airway function and greater respiratory tract inflammation than children with virus-positive low-symptom illnesses or virus-negative upper respiratory tract symptoms. METHODS: We studied 53 children with asthma from Detroit, Michigan, during scheduled surveillance periods and self-reported respiratory illnesses for 1 year. Symptom score, spirometry, fraction of exhaled nitric oxide (FeNO), and nasal aspirate biomarkers, and viral nucleic acid and rhinovirus (RV) copy number were assessed. RESULTS: Of 658 aspirates collected, 22.9% of surveillance samples and 33.7% of respiratory illnesses were virus-positive. Compared with the virus-negative asymptomatic condition, children with severe colds (symptom score ≥5) showed reduced forced expiratory flow at 25% to 75% of the pulmonary volume (FEF25%-75%), higher nasal messenger RNA expression of C-X-C motif chemokine ligand (CXCL)-10 and melanoma differentiation-associated protein 5, and higher protein abundance of CXCL8, CXCL10 and C-C motif chemokine ligands (CCL)-2, CCL4, CCL20, and CCL24. Children with mild (symptom score, 1-4) and asymptomatic infections showed normal airway function and fewer biomarker elevations. Virus-negative cold-like illnesses demonstrated increased FeNO, minimal biomarker elevation, and normal airflow. The RV copy number was associated with nasal chemokine levels but not symptom score. CONCLUSION: Urban children with asthma with high-symptom respiratory viral infections have reduced FEF25%-75% and more elevations of nasal biomarkers than children with mild or symptomatic infections, or virus-negative illnesses.

Influence of viral infection on the relationships between airway cytokines and lung function in asthmatic children.

BACKGROUND: Few longitudinal studies examine inflammation and lung function in asthma. We sought to determine the cytokines that reduce airflow, and the influence of respiratory viral infections on these relationships. METHODS: Children underwent home collections of nasal lavage during scheduled surveillance periods and self-reported respiratory illnesses. We studied 53 children for one year, analyzing 392 surveillance samples and 203 samples from 85 respiratory illnesses. Generalized estimated equations were used to evaluate associations between nasal lavage biomarkers (7 mRNAs, 10 proteins), lung function and viral infection. RESULTS: As anticipated, viral infection was associated with increased cytokines and reduced FVC and FEV1. However, we found frequent and strong interactions between biomarkers and virus on lung function. For example, in the absence of viral infection, CXCL10 mRNA, MDA5 mRNA, CXCL10, IL-4, IL-13, CCL4, CCL5, CCL20 and CCL24 were negatively associated with FVC. In contrast, during infection, the opposite relationship was frequently found, with IL-4, IL-13, CCL5, CCL20 and CCL24 levels associated with less severe reductions in both FVC and FEV1. CONCLUSIONS: In asthmatic children, airflow obstruction is driven by specific pro-inflammatory cytokines. In the absence of viral infection, higher cytokine levels are associated with decreasing lung function. However, with infection, there is a reversal in this relationship, with cytokine abundance associated with reduced lung function decline. While nasal samples may not reflect lower airway responses, these data suggest that some aspects of the inflammatory response may be protective against viral infection. This study may have ramifications for the treatment of viral-induced asthma exacerbations.

Independent and Joint Contributions of Fine Particulate Matter Exposure and Population Vulnerability to Mortality in the Detroit Metropolitan Area.

Fine particulate matter is associated with adverse health outcomes. Exposure to fine particulate matter may disproportionately affect urban communities with larger numbers of vulnerable residents. We used multilevel logistic regression models to estimate the joint effects of fine particulate matter (PM2.5) and population vulnerabilities on cardiopulmonary mortality (CPM). We estimated the health benefits of reductions in PM2.5 across census tracts in the Detroit metropolitan area with varying levels of population vulnerability, using cluster-specific odds ratios scaled to reflect PM2.5-attributable cardiopulmonary risk. PM2.5 and population vulnerability were independently associated with odds of CPM. Odds of CPM and the number of deaths attributable to PM2.5 were greatest in census tracts with both high PM2.5 exposures and population vulnerability. Reducing PM2.5 in census tracts with high PM2.5 would lead to an estimated 18% annual reduction in PM2.5-attributable CPM. Between 78⁻79% of those reductions in CPM would occur within census tracts with high population vulnerabilities. These health benefits of reductions in PM2.5 occurred at levels below current U.S. reference concentrations. Focusing efforts to reduce PM2.5 in the Detroit metropolitan area in census tracts with currently high levels would also lead to greater benefits for residents of census tracts with high population vulnerabilities.

Does Perceived Safety Modify the Effectiveness of a Walking-Group Intervention Designed to Promote Physical Activity?

PURPOSE: To examine whether perceived safety modified the effectiveness of the Walk Your Heart to Health (WYHH) intervention in promoting physical activity and reducing central adiposity in predominantly non-Latino black (henceforth black) and Latino communities. DESIGN: Generalized estimation equations were used to assess modifying effects of perceived safety on the route and perceived neighborhood safety on (1) WYHH participation at 8 weeks and 32 weeks, (2) associations between participation and physical activity, and (3) associations between physical activity and central adiposity. SETTING: Community-based and faith-based organizations in black and Latino communities. PARTICIPANTS: There were 603 adults, aged 18 years and older, who were predominantly black, Latino, and female. MEASURES: Participation and physical activity (piezoelectric pedometer) were measured at each walking session. Perceived safety on the route (questionnaire), perceived neighborhood safety (questionnaire), and waist circumference were measured at baseline, 8 weeks, and 32 weeks. ANALYSIS: Secondary analysis of repeated measures using generalized estimation equations. RESULTS: Retention was 90% at 8 weeks and 64% at 32 weeks. Perceived safety on the route, but not perceived neighborhood safety, dampened participation at 8 weeks but not 32 weeks. Consistent participation in the intervention increased physical activity and reduced central adiposity irrespective of perceived safety on the walking route or perceived neighborhood safety. CONCLUSION: Efforts to improve safety in conjunction with interventions focused on increasing physical activity can work toward improving physical activity for blacks and Latinos, leading to a myriad of improved health outcomes including reduced central adiposity.

Independent Effects of Neighborhood Poverty and Psychosocial Stress on Obesity Over Time.

The objective of the study was to examine the independent effects of neighborhood poverty and psychosocial stress on increases in central adiposity over time. Data are from a community sample of 157 Non-Hispanic Black, Non-Hispanic White, and Hispanic adults collected in 2002-2003 and 2007-2008, and from the 2000 Decennial Census. The dependent variable was waist circumference. Independent variables included neighborhood poverty, perceived neighborhood physical environment, family stress, safety stress, everyday unfair treatment, and a cumulative stress index. Weighted 3-level hierarchical linear regression models for a continuous outcome were used to assess the effects of neighborhood poverty and psychosocial stress on central adiposity over time. We also assessed whether psychosocial stress mediated the association between neighborhood poverty and central adiposity. Neighborhood poverty and everyday unfair treatment at baseline were independently associated with increases in central adiposity over time, accounting for the other indicators of stress. Perceptions of the neighborhood physical environment and cumulative stress mediated associations between neighborhood poverty and central adiposity. Results suggest that residing in neighborhoods with higher concentrations of poverty and exposure to everyday unfair treatment independently heighten risk of increased central adiposity over time. Associations between neighborhood poverty and central adiposity were mediated by perceptions of the neighborhood physical environment and by the cumulative stress index. Public health strategies to reduce obesity should consider neighborhood poverty and exposure to multiple sources of psychosocial stress, including everyday unfair treatment.

Do Neighborhood Demographics Modify Walking Group Intervention Effectiveness in Urban Neighborhoods?

OBJECTIVES: We assessed the effects of neighborhood composition on effectiveness of the Walk Your Heart to Health (WYHH) intervention in promoting physical activity and reducing cardiovascular risk (CVR) in low-to-moderate-income, predominantly non-Latino Black (NLB) and Latino communities. METHOD: Multilevel models assessed modifying effects of neighborhood composition on (1) WYHH adherence/participation at 8 weeks and 32 weeks, (2) associations between participation and steps, and (3) associations between steps and CVR. RESULTS: Approximately 90% of participants were women. Neither neighborhood poverty nor racial composition modified intervention participation at 8 weeks. At 32 weeks, residents of high percentage-NLB neighborhoods that also had high poverty rates had reduced participation. Neighborhood composition did not modify associations between participation and steps or between steps and CVR. Neighborhood percentage poverty and NLB were positively associated with CVR. CONCLUSION: Positive associations between participation in the WYHH program and physical activity, and CVR did not differ by neighborhood composition. Efforts to address challenges to long-term participation are warranted for residents of racially segregated, high-poverty neighborhoods. Residents of racially segregated neighborhoods with high concentrations of poverty experience disproportionately high risk for cardiovascular disease and can benefit from interventions such as WYHH that increase physical activity and reduce CVR.

NEIGHBOURHOOD POVERTY, PERCEIVED DISCRIMINATION AND CENTRAL ADIPOSITY IN THE USA: INDEPENDENT ASSOCIATIONS IN A REPEATED MEASURES ANALYSIS.

This study examines the independent effects of neighbourhood context (i.e. neighbourhood poverty) and exposure to perceived discrimination in shaping risk of obesity over time. Weighted three-level hierarchical linear regression models for a continuous outcome were used to assess the independent effects of neighbourhood poverty and perceived discrimination on obesity over time in a sample of 157 non-Hispanic Black, non-Hispanic White and Hispanic adults in Detroit, USA, in 2002/2003 and 2007/2008. Independent associations were found between neighbourhood poverty and perceived discrimination with central adiposity over time. Residents of neighbourhoods with high concentrations of poverty were more likely to show increases in central adiposity compared with those in neighbourhoods with lower concentrations of poverty. In models adjusted for BMI, neighbourhood poverty at baseline was associated with a greater change in central adiposity among participants who lived in neighbourhoods in the second (B=3.79, p=0.025) and third (B=3.73, p=0.024) poverty quartiles, compared with those in the lowest poverty neighbourhoods. The results from models that included both neighbourhood poverty and perceived discrimination showed that both were associated with increased risk of increased central adiposity over time. Residents of neighbourhoods in the second (B=9.58, p<0.001), third (B=8.25, p=0.004) and fourth (B=7.66, p=0.030) quartiles of poverty were more likely to show greater increases in central adiposity over time, compared with those in the lowest poverty quartile, with mean discrimination at baseline independently and positively associated with increases in central adiposity over time (B=2.36, p=0.020). The results suggest that neighbourhood poverty and perceived discrimination are independently associated with a heightened risk of increase in central adiposity over time. Efforts to address persistent disparities in central adiposity in the USA should include strategies to reduce high concentrations of neighbourhood poverty as well as discrimination.

RACE AND THE DISTRIBUTION OF SOCIAL AND PHYSICAL ENVIRONMENTAL RISK: A Case Example from the Detroit Metropolitan Area.

Since W. E. B. Du Bois documented the physical and social environments of Philadelphia's predominantly African American Seventh Ward over a century ago, there has been continued interest in understanding the distribution of social and physical environments by racial make-up of communities. Characterization of these environments allows for documentation of inequities, identifies communities which encounter heightened risk, and can inform action to promote health equity. In this paper, we apply and extend Du Bois's approach to examine the contemporary distribution of physical environmental exposures, health risks, and social vulnerabilities in the Detroit metropolitan area, one of the most racially-segregated areas in the United States. We begin by mapping the proximity of sensitive populations to hazardous land uses, their exposure to air pollutants and associated health risks, and social vulnerabilities, as well as cumulative risk (combined proximity, exposure, and vulnerability), across Census tracts. Next, we assess, quantitatively, the extent to which communities of color experience excess burdens of environmental exposures and associated health risks, economic and age-related vulnerabilities, and cumulative risk. The results, depicted in maps presented in the paper, suggest that Census tracts with greater proportions of people of color disproportionately encounter physical environmental exposures, socioeconomic vulnerabilities, and combined risk. Quantitative tests of inequality confirm these distributions, with statistically greater exposures, vulnerabilities, and cumulative risk in Census tracts with larger proportions of people of color. Together, these findings identify communities that experience disproportionate cumulative risk in the Detroit metropolitan area and quantify the inequitable distribution of risk by Census tract relative to the proportion of people of color. They identify clear opportunities for prioritizing communities for legislative, regulatory, policy, and local actions to promote environmental justice and health equity.

Effectiveness of a walking group intervention to promote physical activity and cardiovascular health in predominantly non-Hispanic black and Hispanic urban neighborhoods: findings from the walk your heart to health intervention.

OBJECTIVES: The purpose of this study was to evaluate the effectiveness of the Walk Your Heart to Health (WYHH) intervention, one component of the multilevel Community Approaches to Cardiovascular Health: Pathways to Heart Health (CATCH:PATH) intervention designed to promote physical activity and reduce cardiovascular risk among non-Hispanic Black and Hispanic residents of Detroit, Michigan. The study was designed and implemented using a community-based participatory research approach that actively engaged community residents, health service providers and academic researchers. It was implemented between 2009 and 2012. METHOD: WYHH was a 32-week community health promoter-facilitated walking group intervention. Groups met three times per week at community-based or faith-based organizations, and walked for 45 to 90 minutes (increasing over time). The study used a cluster randomized control design to evaluate effectiveness of WYHH, with participants randomized into intervention or lagged intervention (control) groups. Psychosocial, clinical, and anthropometric data were collected at baseline, 8, and 32 weeks, and pedometer step data tracked using uploadable peisoelectric pedometers. RESULTS: Participants in the intervention group increased steps significantly more during the initial 8-week intervention period, compared with the control group (ß = 2004.5, p = .000). Increases in physical activity were associated with reductions in systolic blood pressure, fasting blood glucose, total cholesterol, waist circumference and body mass index at 8 weeks, and maintained at 32 weeks. CONCLUSION: The WYHH community health promoter-facilitated walking group intervention was associated with significant reductions in multiple indicators of cardiovascular risk among predominantly Hispanic and non-Hispanic Black participants in a low-to-moderate income urban community. Such interventions can contribute to reductions in racial, ethnic, and socioeconomic inequities in cardiovascular mortality.

Effects of particulate matter and antioxidant dietary intake on blood pressure.

OBJECTIVES: We assessed 2 pathways through which dietary antioxidants may counter adverse effects of exposure to particulate matter less than 2.5 micrometers in diameter (PM2.5) on blood pressure (BP): main (compensatory) and modifying (protective) models. METHODS: We used 2002 to 2003 data from the Detroit Healthy Environments Partnership community survey conducted with a multiethnic sample of adults (n = 347) in low- to moderate-income, predominantly Hispanic and non-Hispanic Black neighborhoods in Detroit, Michigan. We used generalized estimating equations to test the effects of ambient exposure to PM2.5 and dietary antioxidant intake on BP, with adjustment for multiple confounders. RESULTS: Dietary antioxidant intake was inversely associated with systolic BP (b = -0.5; P < .05) and pulse pressure (b = -0.6; P < .05) in neighborhoods closest to major sources of air pollutants. Adverse effects of PM2.5 remained significant after accounting for antioxidant intakes. Exploratory analyses suggested potential modifying effects of antioxidant intake on associations between ambient PM2.5 exposure and BP. CONCLUSIONS: Interventions to improve access to antioxidant-rich foods in polluted urban areas may be protective of cardiovascular health. However, efforts to reduce PM2.5 exposure remain critical for cardiovascular health promotion.

Associations between observed neighborhood characteristics and physical activity: findings from a multiethnic urban community.

BACKGROUND: There is growing interest in the contributions of characteristics of the neighborhood environment to inequalities in physical activity. However, few studies have examined the relationship between observed neighborhood environmental characteristics and physical activity in a multiethnic urban area. PURPOSE: The purpose of this study was to assess relationships between neighborhood environments and physical activity and the extent to which these associations varied by demographic characteristics or perceptions of the physical and social environment. METHODS: Cross-sectional analyses drew upon data collected from a stratified proportional probability sample of non-Hispanic Black, Hispanic and non-Hispanic White (NHW) adults (n = 919) in low-to-moderate income neighborhoods in Detroit, Michigan. Physical activity was assessed as self-reported duration and frequency of vigorous and moderate physical activity. Observed physical environment was assessed through systematic social observation by trained observers on blocks adjacent to survey respondents' residences. RESULTS: We find a positive association of sidewalk condition with physical activity, with stronger effects for younger compared with older residents. In addition, physical disorder was more negatively associated with physical activity among NHW and older residents. CONCLUSIONS: These findings suggest that sidewalk improvements and reductions in physical disorder in urban communities may promote greater equity in physical activity.

Air pollution and respiratory symptoms among children with asthma: vulnerability by corticosteroid use and residence area.

RATIONALE: Information on how ambient air pollution affects susceptible populations is needed to ensure protective air quality standards. OBJECTIVES: To estimate the effect of community-level ambient particulate matter (PM) and ozone (O) on respiratory symptoms among primarily African-American and Latino, lower-income asthmatic children living in Detroit, Michigan and to evaluate factors associated with heterogeneity in observed health effects. METHODS: A cohort of 298 children with asthma was studied prospectively from 1999 to 2002. For 14days each season over 11 seasons, children completed a respiratory symptom diary. Simultaneously, ambient pollutant concentrations were measured at two community-level monitoring sites. Logistic regression models using generalized estimating equations were fit for each respiratory symptom in single pollutant models, looking for interactions by area or by corticosteroid use, a marker of more severe asthma. Exposures of interest were: daily concentrations of PM<10µm, <2.5µm, and between 10 and 2.5µm in aerodynamic diameter (PM, PM, and PM respectively), the daily 8-hour maximum concentration of O (8HrPeak), and the daily 1-hour maximum concentration of O (1HrPeak). RESULTS: Outdoor PM, PM, 8HrPeak, and 1HrPeak O concentrations were associated with increased odds of respiratory symptoms, particularly among children using corticosteroid medication and among children living in the southwest community of Detroit. Similar patterns of associations were not seen with PM. CONCLUSIONS: PM and O at levels near or below annual standard levels are associated with negative health impact in this population of asthmatic children. Variation in effects within the city of Detroit and among the subgroup using steroids emphasizes the importance of spatially refined exposure assessment and the need for further studies to elucidate mechanisms and effective risk reduction interventions.