Recruitment strategies for a pragmatic cluster randomized oral health trial in pediatric primary care settings.

OBJECTIVES: To describe multilevel recruitment strategies for an ongoing clinical trial in pediatric primary care settings, and assess adoption and reach of these strategies via the RE-AIM framework. METHODS: This study is part of a larger pragmatic cluster randomized clinical trial focused on the effectiveness of interventions on the practice, provider, and caregiver levels on dental utilization for Medicaid-enrolled 3-6 year old children. Pediatric practices were recruited according to the proportion of Medicaid-eligible children, geographic region, and County. In accordance with the RE-AIM framework, providers reached were those approached directly and consented, and those who participated in the intervention training adopted to deliver the intervention. Caregivers reached were those approached and consented at their child's well-child visit to participate in the trial. RESULTS: Recruitment goals were met over a 21 month period, with an overall enrollment of 18 practices, 62 providers, and 1024 caregivers-child dyads. The majority of practices enrolled were small, suburban, and located in an urban county. The participation rates among approached providers and caregivers was 93% and 84% respectively. Enablers for recruitment was the one-on-one interaction with the provider and caregivers. Barriers to recruitment for caregivers included no-shows and cancellations at well-child visits. Adoption of intervention among providers was high, and caregiver reached were representative of the eligible target population. CONCLUSIONS: Active approaches to recruitment, such as utilizing opinion leaders, in-person recruitment, and building relationships with practice staff, can result in successful enrollment and imp lementation of a multi-level intervention in pediatric primary care settings.

Formative and Pilot Study for an Effectiveness-Implementation Hybrid Cluster Randomized Trial to Incorporate Oral Health Activities into Pediatric Well-Child Visits.

Background: Dental caries in pediatric patients are noted to have broad impacts on systemic health and well-being. Thus, utilizing an effectiveness-implementation hybrid I design, the Pediatric Providers Against Cavities in Children's Teeth (PACT) trial is investigating multi-level interventions at the practice (incorporation of oral health in electronic medical record [EMR]) and provider levels (theory-based didactic and skills training to communicate oral health facts to parent/caregiver, give a prescription to see a dentist and a list of area dentists) to increase dental utilization among 3 to 6 year old Medicaid-enrolled children attending well-child visits (WCV). The formative and pilot work for the larger main trial are presented. Methods: Formative work-Focus groups with 26 participants (Community leaders, providers, parent/caregivers); and key informant interviews with practice leadership (n = 4). Topics discussed were: core oral health (OH) information to communicate at WCVs and study logistics. Transcripts were coded and analyzed using Atlas.ti; Pilot study was refined using the formative findings and was conducted at two pediatric practices to test the implementation of: the provider didactic and skills training curriculum; EMR incorporation of four OH questions; logistics of incorporating OH activities at a WCV; and parent/caregiver recruitment. Results: Formative work showed that providers and parent/caregivers required knowledge of dental caries, and a list of area Medicaid-accepting dentists. Providers and practice leadership advised on the logistics of incorporating oral health into WCVs. All groups suggested asking parent/caregivers their preferred method of contact and emphasizing importance of OH to motivate participation. Utilizing these findings, the curriculum and protocol was revised. The pilot study in two practices successfully implemented the protocol as follows: all seven providers were trained in two 45 min didactic education and skills session; incorporation of OH questions into practices EMR; recruited 86 child-parent dyads (95% participation) at the WCV; providers delivered the OH intervention to parent/caregivers in <2 min and 90% completed EMR documentation of OH questions. These findings were instrumental in finalizing the main PACT trial in 18 practices. The RE-AIM framework is used in the main trial to collect effectiveness and implementation measures at baseline and follow-up visits. Conclusions: The formative and pilot findings were instrumental in refining the OH intervention and protocol which has resulted in successful implementation of the main trial. Trial Registration: Clinical trials.gov, Registered 9 November 2017, NCT03385629.

Association between ambient air pollution and breast cancer risk: The multiethnic cohort study.

Previous studies using different exposure methods to assess air pollution and breast cancer risk among primarily whites have been inconclusive. Air pollutant exposures of particulate matter and oxides of nitrogen were estimated by kriging (NOx , NO2 , PM10 , PM2.5 ), land use regression (LUR, NOx , NO2 ) and California Line Source Dispersion model (CALINE4, NOx , PM2.5 ) for 57,589 females from the Multiethnic Cohort, residing largely in Los Angeles County from recruitment (1993-1996) through 2010. Cox proportional hazards models were used to examine the associations between time-varying air pollution and breast cancer incidence adjusting for confounding factors. Stratified analyses were conducted by race/ethnicity and distance to major roads. Among all women, breast cancer risk was positively but not significantly associated with NOx (per 50 parts per billion [ppb]) and NO2 (per 20 ppb) determined by kriging and LUR and with PM2.5 and PM10 (per 10 µg/m3 ) determined by kriging. However, among women who lived within 500 m of major roads, significantly increased risks were observed with NOx (hazard ratio [HR] = 1.35, 95% confidence interval [95% CI]: 1.02-1.79), NO2 (HR = 1.44, 95% CI: 1.04-1.99), PM10 (HR = 1.29, 95% CI: 1.07-1.55) and PM2.5 (HR = 1.85, 95% CI: 1.15-2.99) determined by kriging and NOx (HR = 1.21, 95% CI:1.01-1.45) and NO2 (HR = 1.26, 95% CI: 1.00-1.59) determined by LUR. No overall associations were observed with exposures assessed by CALINE4. Subgroup analyses suggested stronger associations of NOx and NO2 among African Americans and Japanese Americans. Further studies of multiethnic populations to confirm the effects of air pollution, particularly near-roadway exposures, on the risk of breast cancer is warranted.

Estimated Nonreimbursed Costs for Care Coordination for Children With Medical Complexity.

: media-1vid110.1542/5852348672001PEDS-VA_2017-3562Video Abstract BACKGROUND AND OBJECTIVES: Multidisciplinary care teams may improve health and control total cost for children with medical complexity (CMC). We aim to quantify the time required to perform nonreimbursed care coordination activities by a multidisciplinary care coordination program for CMC and to estimate the direct salary costs of that time. METHODS: From April 2013 to October 2015, program staff tracked time spent in practicably measured nonbilled care coordination efforts. Staff documented the discipline involved, the method used, and the target of the activity. Cost was estimated by multiplying the time spent by the typical salary of the type of personnel performing the activity. RESULTS: Staff logged 53 148 unique nonbilled care coordination activities for 208 CMC. Dietitians accounted for 26% of total time, physicians and nurse practitioners 24%, registered nurses 29%, and social workers 21% (1.8, 2.3, 1.2, and 1.4 hours per CMC per month per full-time provider, respectively). Median time spent in nonreimbursed care coordination was 2.3 hours per child per month (interquartile range 0.8-6.8). Enrollees required substantially greater time in their first program month than thereafter (median 6.7 vs 2.1 hours per CMC per month). Based on 2015 national salary data, the adjusted median estimated cost of documented activities ranged from $145 to $210 per CMC per month. CONCLUSIONS: In this multidisciplinary model, care coordination for CMC required substantial staff time, even without accounting for all activities, particularly in the first month of program enrollment. Continued advocacy is warranted for the reimbursement of care coordination activities for CMC.

Impact of individual and neighborhood factors on socioeconomic disparities in localized and advanced prostate cancer risk.

PURPOSE: The reasons behind socio-economic disparities in prostate cancer incidence remain unclear. We tested the hypothesis that individual-level factors act jointly with neighborhood-level social and built environment factors to influence prostate cancer risk and that specific social and built environment factors contribute to socio-econmic differences in risk. METHODS: We used multi-level data, combining individual-level data (including education and known prostate cancer risk factors) for prostate cancer cases (n = 775) and controls (n = 542) from the San Francisco Bay Area Prostate Cancer Study, a population-based case-control study, with contextual-level data on neighborhood socio-economic status (nSES) and specific social and built environment factors from the California Neighborhoods Data System. Multivariable logistic regression models were used to compute adjusted odds ratios separately for localized and advanced stage prostate cancer while controlling for neighborhood clustering. RESULTS: We found a more than twofold increased risk of both localized and advanced prostate cancer with increasing levels of nSES, and decreased risk of advanced prostate cancer with increasing levels of education. For localized disease, the nSES association was largely explained by known prostate cancer risk factors and specific neighborhood environment factors; population density, crowding, and residential mobility. For advanced disease, associations with education and nSES were not fully explained by any available individual- or neighborhood-level factors. CONCLUSIONS: These results demonstrate the importance of specific neighborhood social and built environment factors in understanding risk of localized prostate cancer. Further research is needed to understand the factors underpinning the associations between individual- and neighborhood-level SES and risk of advanced prostate cancer.

Disparities in hepatocellular carcinoma incidence by race/ethnicity and geographic area in California: Implications for prevention.

BACKGROUND: The incidence of hepatocellular carcinoma (HCC) has been rising rapidly in the United States. California is an ethnically diverse state with the largest number of incident HCC cases in the country. Characterizing HCC disparities in California may inform priorities for HCC prevention. METHODS: By using data from the Surveillance, Epidemiology, and End Results 18-Registry Database and the California Cancer Registry, age-adjusted HCC incidence in California from 2009 through 2013 was calculated by race/ethnicity and neighborhood ethnic enclave status. A geographic analysis was conducted using Medical Service Study Areas (MSSAs) as the geographic unit, and race/ethnicity-specific standardized incidence ratios (SIRs) were calculated to identify MSSAs with higher-than-expected HCC incidence compared with the statewide average. RESULTS: During 2009 through 2013, the age-adjusted incidence of HCC in California was the highest in Asians/Pacific Islanders (APIs) and Hispanics (>100% higher than whites), especially those living in more ethnic neighborhoods (20%-30% higher than less ethnic neighborhoods). Of the 542 MSSAs statewide, 42 had elevated HCC incidence (SIR ≥ 1.5; lower bound of 95% confidence interval > 1) for whites, 14 for blacks, 24 for APIs, and 36 for Hispanics. These MSSAs have 24% to 52% higher proportions of individuals below the 100% federal poverty line than other MSSAs. CONCLUSIONS: APIs and Hispanics residing in more ethnic neighborhoods and individuals residing in lower income neighborhoods require more extensive preventive efforts tailored toward their unique risk factor profiles. The current race/ethnicity-specific geographic analysis can be extended to other states to inform priorities for HCC targeted prevention at the subcounty level, eventually reducing HCC burden in the country.

Impact of individual and neighborhood factors on disparities in prostate cancer survival.

BACKGROUND: We addressed the hypothesis that individual-level factors act jointly with social and built environment factors to influence overall survival for men with prostate cancer and contribute to racial/ethnic and socioeconomic (SES) survival disparities. METHODS: We analyzed multi-level data, combining (1) individual-level data from the California Collaborative Prostate Cancer Study, a population-based study of non-Hispanic White (NHW), Hispanic, and African American prostate cancer cases (N = 1800) diagnosed from 1997 to 2003, with (2) data on neighborhood SES (nSES) and social and built environment factors from the California Neighborhoods Data System, and (3) data on tumor characteristics, treatment and follow-up through 2009 from the California Cancer Registry. Multivariable, stage-stratified Cox proportional hazards regression models with cluster adjustments were used to assess education and nSES main and joint effects on overall survival, before and after adjustment for social and built environment factors. RESULTS: African American men had worse survival than NHW men, which was attenuated by nSES. Increased risk of death was associated with residence in lower SES neighborhoods (quintile 1 (lowest nSES) vs. 5: HR = 1.56, 95% CI: 1.11-2.19) and lower education (

Characterizing the neighborhood obesogenic environment in the Multiethnic Cohort: a multi-level infrastructure for cancer health disparities research.

PURPOSE: We characterized the neighborhood obesogenic environment in the Multiethnic Cohort (MEC) by examining the associations of obesity with attributes of the social and built environment, establishing a multi-level infrastructure for future cancer research. METHODS: For 102,906 African American, Japanese American, Latino, and white MEC participants residing predominately in Los Angeles County, baseline residential addresses (1993-1996) were linked to census and geospatial data, capturing neighborhood socioeconomic status (nSES), population density, commuting, food outlets, amenities, walkability, and traffic density. We examined neighborhood attributes and obesity (body mass index ≥ 30 kg/m2) associations using multinomial logistic regression, adjusting for individual-level (e.g., demographics, physical activity, and diet) and neighborhood-level factors. RESULTS: NSES was associated with obesity among African Americans, Latinos, and whites (p-trend ≤ 0.02), with twofold higher odds (adjusted odds ratios, 95% confidence intervals) for living in the lowest versus highest quintile among African American women (2.07, 1.62-2.65), white men (2.11, 1.29-3.44), and white women (2.50, 1.73-3.61). Lower density of businesses among African American and white women and lower traffic density among white men were also associated with obesity (p-trends ≤ 0.02). CONCLUSIONS: Our study highlights differential impacts of neighborhood factors across racial/ethnic groups and establishes the foundation for multi-level studies of the neighborhood context and obesity-related cancers.

Association between the neighborhood obesogenic environment and colorectal cancer risk in the Multiethnic Cohort.

BACKGROUND: Information on the role of the neighborhood environment and colorectal cancer risk is limited. We investigated the association between a comprehensive suite of possible obesogenic neighborhood attributes (socioeconomic status, population density, restaurant and retail food environments, numbers of recreational facilities and businesses, commute patterns, traffic density, and street connectivity) and colorectal cancer risk in the Multiethnic Cohort Study. METHODS: Among 81,197 eligible participants living in California (35,397 males and 45,800 females), 1973 incident cases (981 males and 992 females) of invasive colorectal cancer were identified between 1993 and 2010. Separately for males and females, multivariable Cox regression models were used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for colorectal cancer risk overall and by racial/ethnic group (African American, Japanese American, Latino, white). RESULTS: In males, higher traffic density was associated with an increased risk of colorectal cancer (HR=1.29, 95% CI: 1.03-1.61, p=0.03, for quintile 5 vs. quintile 1; p-trend=0.06). While this association may be due to chance, this pattern was seen (albeit non-statistically significant) in all racial/ethnic groups except whites. There were no other significant associations between other neighborhood obesogenic attributes and colorectal cancer risk. CONCLUSION: Findings from our large racial/ethnically diverse cohort suggest neighborhood obesogenic characteristics are not strongly associated with the risk of colorectal cancer.

Contextual Impact of Neighborhood Obesogenic Factors on Postmenopausal Breast Cancer: The Multiethnic Cohort.

Background: While obesity is well-understood to increase breast cancer risk, the role of the neighborhood obesogenic environment, encompassing social and built environment attributes that influence body size, is poorly understood.Methods: Using principal components factor analysis, five composite factors [neighborhood socioeconomic status (nSES), urban, mixed-land development, unhealthy food environment, parks] on the basis of geospatial data were developed to characterize the obesogenic environment for 48,247 postmenopausal women in the Multiethnic Cohort, residing predominately in Los Angeles County. We used Cox proportional hazards regression to examine the association between neighborhood obesogenic factors and breast cancer risk (n = 2,341 cases after 17 years of follow-up), adjusting for body mass index (BMI), weight gain since age 21, education, established risk factors, other neighborhood factors, and clustering by block group.Results: Lower nSES was associated with lower breast cancer risk [quintile 1 vs. 5: HR, 0.79; 95% confidence interval (CI), 0.66-0.95], with a more pronounced association observed in Latinos (quintile 1 vs. 5: HR, 0.60; 95% CI, 0.43-0.85). More urban environments were associated with lower breast cancer risk in Japanese Americans (quintile 5 vs. 1: HR, 0.49; 95% CI, 0.26-0.90), and lower mixed-land development was associated with higher breast cancer risk in Latinos (quintile 1 vs. 5: HR, 1.46; 95% CI, 1.10-1.93).Conclusions: Obesogenic neighborhood environment factors, especially nSES, urbanicity, and mixed-land development, were differentially and independently associated with breast cancer risk in this multiethnic population.Impact: These findings highlight the need for additional studies of the driving contextual aspects of nSES that influence breast cancer risk. Cancer Epidemiol Biomarkers Prev; 26(4); 480-9. ©2017 AACRSee all the articles in this CEBP Focus section, "Geospatial Approaches to Cancer Control and Population Sciences."

Pediatric Accountable Care Organizations: Insight From Early Adopters.

Partly in response to incentives in the Affordable Care Act, there has been major growth in accountable care organizations (ACO) in both the private and public sectors. For several reasons, growth of ACOs in pediatric care has been more modest than for older populations. The American Academy of Pediatrics collaborated with Leavitt Partners, LLC, to carry out a study of pediatric ACOs, including a series of 5 case studies of diverse pediatric models, a scan of Medicaid ACOs, and a summit of leaders in pediatric ACO development. These collaborative activities identified several issues in ACO formation and sustainability in pediatric settings and outlined a number of opportunities for the pediatric community in areas of organization, model change, and market dynamics; payment, financing, and contracting; quality and value; and use of new technologies. These insights can guide future work in pediatric ACO development.

Impact of Social and Built Environment Factors on Body Size among Breast Cancer Survivors: The Pathways Study.

Background: As social and built environment factors have been shown to be associated with physical activity, dietary patterns, and obesity in the general population, they likely also influence these health behaviors among cancer survivors and thereby impact survivorship outcomes.Methods: Enhancing the rich, individual-level survey and medical record data from 4,505 breast cancer survivors in the Pathways Study, a prospective cohort drawn from Kaiser Permanente Northern California, we geocoded baseline residential addresses and appended social and built environment data. With multinomial logistic models, we examined associations between neighborhood characteristics and body mass index and whether neighborhood factors explained racial/ethnic/nativity disparities in overweight/obesity.Results: Low neighborhood socioeconomic status, high minority composition, high traffic density, high prevalence of commuting by car, and a higher number of fast food restaurants were independently associated with higher odds of overweight or obesity. The higher odds of overweight among African Americans, U.S.-born Asian Americans/Pacific Islanders, and foreign-born Hispanics and the higher odds of obesity among African Americans and U.S.-born Hispanics, compared with non-Hispanic whites, remained significant, although somewhat attenuated, when accounting for social and built environment features.Conclusions: Addressing aspects of neighborhood environments may help breast cancer survivors maintain a healthy body weight.Impact: Further research in this area, such as incorporating data on individuals' perceptions and use of their neighborhood environments, is needed to ultimately inform multilevel interventions that would ameliorate such disparities and improve outcomes for breast cancer survivors, regardless of their social status (e.g., race/ethnicity, socioeconomic status, nativity). Cancer Epidemiol Biomarkers Prev; 26(4); 505-15. ©2017 AACRSee all the articles in this CEBP Focus section, "Geospatial Approaches to Cancer Control and Population Sciences."

Racial/Ethnic Differences in the Impact of Neighborhood Social and Built Environment on Breast Cancer Risk: The Neighborhoods and Breast Cancer Study.

Background: Neighborhood socioeconomic status (nSES) has been found to be associated with breast cancer risk. It remains unclear whether this association applies across racial/ethnic groups independent of individual-level factors and is attributable to other neighborhood characteristics.Methods: We examined the independent and joint associations of education and nSES with odds of breast cancer. Residential addresses were geocoded for 2,838 cases and 3,117 controls and linked to nSES and social and built environment characteristics. We estimated ORs and 95% confidence intervals (CI) using multilevel logistic regression controlling for individual-level breast cancer risk factors and assessed the extent to which nSES associations were due to neighborhood characteristics.Results: Women living in the highest versus lowest nSES quintile had a nearly 2-fold greater odds of breast cancer, with elevated odds (adjusted ORs, 95% CI) for non-Hispanic whites (NHWs; 2.27; 1.45-3.56), African Americans (1.74; 1.07-2.83), U.S.-born Hispanics (1.82; 1.19-2.79), and foreign-born Hispanics (1.83; 1.06-3.17). Considering education and nSES jointly, ORs were increased for low education/high nSES NHWs (1.83; 1.14-2.95), high education/high nSES NHWs (1.64; 1.06-2.54), and high education/high nSES foreign-born Hispanics (2.17; 1.52-3.09) relative to their race/ethnicity/nativity-specific low education/low nSES counterparts. Adjustment for urban and mixed-land use characteristics attenuated the nSES associations for most racial/ethnic/nativity groups except NHWs.Conclusions: Our study provides empirical evidence for a role of neighborhood environments in breast cancer risk, specifically social and built environment attributes.Impact: Considering the role of neighborhood characteristics among diverse populations may offer insights to understand racial/ethnic disparities in breast cancer risk. Cancer Epidemiol Biomarkers Prev; 26(4); 541-52. ©2017 AACR.

Tracing a Path to the Past: Exploring the Use of Commercial Credit Reporting Data to Construct Residential Histories for Epidemiologic Studies of Environmental Exposures.

Large-scale environmental epidemiologic studies often rely on exposure estimates based on linkage to residential addresses. This approach, however, is limited by the lack of residential histories typically available for study participants. Our objective was to evaluate the feasibility of using address data from LexisNexis (a division of RELX, Inc., Dayton, Ohio), a commercially available credit reporting company, to construct residential histories for participants in the California Teachers Study (CTS), a prospective cohort study initiated in 1995-1996 to study breast cancer (n = 133,479). We evaluated the degree to which LexisNexis could provide retrospective addresses prior to study enrollment, as well as the concordance with existing prospective CTS addresses ascertained at the time of the completion of 4 self-administered questionnaires. For approximately 80% of CTS participants, LexisNexis provided at least 1 retrospective address, including nearly 25,000 addresses completely encompassed by time periods prior to enrollment. This approach more than doubled the proportion of the study population for whom we had an address of residence during the childbearing years-an important window of susceptibility for breast cancer risk. While overall concordance between the prospective addresses contained in these 2 data sources was good (85%), it was diminished among black women and women under the age of 40 years.

Association between Serum Polybrominated Diphenyl Ether Levels and Residential Proximity to Solid-Waste Facilities.

As consumer products treated with polybrominated diphenyl ethers (PBDEs) reach the end of their life cycle, they often are discarded into solid-waste facilities, offering a potential reservoir for exposure. The likelihood of exposures to PBDEs by residents living near those sites rarely has been explored. This study collected blood samples from 923 female participants in the California Teachers Study in 2011-2013 and examined the association between participants' residential proximity to solid-waste facilities with potential release of PBDEs and serum levels of three congeners (BDE-47, BDE-100, and BDE-153). General linear regression analysis was used to examine the association, adjusting for age, race, body-mass index, neighborhood socioeconomic status, and urban residency. Compared to participants living >10 km from any selected site, those living within 2 km had 45% higher BDE-47 (95% CI: 5-100%) and BDE-100 (95% CI: 0-109%) levels, and those living between 2 and 10 km had 35% higher BDE-47 (95% CI: 0-82%) and 29% higher BDE-100 (95% CI: -9 to 82%) levels. No associations were found for BDE-153. Living close to some solid waste sites may be related to higher serum BDE-47 and BDE-100 levels. Studies with comprehensive exposure assessments are needed to confirm these initial observations.

Impact of neighborhoods and body size on survival after breast cancer diagnosis.

With data from the Neighborhoods and Breast Cancer Study, we examined the associations between body size, social and built environments, and survival following breast cancer diagnosis among 4347 women in the San Francisco Bay Area. Lower neighborhood socioeconomic status and greater neighborhood crowding were associated with higher waist-to-hip ratio (WHR). After mutual adjustment, WHR, but not neighborhood characteristics, was positively associated with overall mortality and marginally with breast cancer-specific mortality. Our findings suggest that WHR is an important modifiable prognostic factor for breast cancer survivors. Future WHR interventions should account for neighborhood characteristics that may influence WHR.

Residential exposure to estrogen disrupting hazardous air pollutants and breast cancer risk: the California Teachers Study.

BACKGROUND: Some studies show increased breast cancer risk from exposure to xenoestrogens, but few have explored exposures via ambient air, which could impact large populations. OBJECTIVES: This study explored the association between breast cancer risk and residential exposures to ambient estrogen disruptors among participants in a large cohort study, the California Teachers Study. METHODS: Participants consisted of 112,379 women free of breast cancer and living at a California address in 1995/1996. Eleven hazardous air pollutants from the US Environmental Protection Agency 2002 list were identified as estrogen disruptors based on published endocrine disrupting chemical lists and literature review. Census-tract estrogen disruptor air concentrations modeled by the US Environmental Protection Agency in 2002 were assigned to participants' baseline addresses. Cox proportional hazards models were used to estimate hazard ratios associated with exposure to each estrogen disruptor and a summary measure of nine estrogenic hazardous air pollutants among all participants and selected subgroups, adjusting for age, race/birthplace, socioeconomic status, and known breast cancer risk factors. RESULTS: Five thousand three hundred sixty-one invasive breast cancer cases were identified between 1995 and 2010. No associations were found between residential exposure to ambient estrogen disruptors and overall breast cancer risk or hormone receptor-positive breast cancer risk, nor among targeted subgroups of participants (pre-/peri-menopausal women, post-menopausal women, never-smokers, non-movers, and never-smoking non-movers). However, elevated risks for hormone receptor-negative tumors were observed for higher exposure to cadmium compounds and possibly inorganic arsenic among never-smoking non-movers. CONCLUSION: Long-term, low-dose exposure to ambient cadmium compounds or possibly inorganic arsenic may be a risk factor for breast cancer.

Hazardous air pollutants and breast cancer risk in California teachers: a cohort study.

BACKGROUND: Studies suggest that higher breast cancer rates in urban areas persist after accounting for the prevalence of known risk factors, leading to speculation that urban environmental exposures, such as air pollution, may play a role in the etiology of breast cancer. Combining modeled ambient air concentrations with data from a large prospective cohort of California women with over 15 years of follow-up, we examined the relationship between breast cancer incidence and modeled concentrations of air pollutants shown to be mammary gland carcinogens (MGCs). METHODS: The study population of 112,378 California Teachers Study participants included 5,676 women diagnosed with invasive breast cancer. Modeled annual average ambient air concentrations of 24 MGCs from the U.S. Environmental Protection Agency were linked to participants' addresses. Cox proportional hazards models were used to estimate hazard rate ratios and 95% confidence intervals associated with residential MGC levels. MGCs were examined individually and as a combined summary variable for all participants, in selected subsets, and by tumor hormone responsiveness. RESULTS: Initial models yielded some evidence for increased risk for several compounds, including acrylamide, carbon tetrachloride, chloroprene, 4,4'-methylene bis(2-chloroaniline), propylene oxide, and vinyl chloride, but after adjustment for multiple comparisons, only results for propylene oxide and vinyl chloride remained statistically significant. In subset analyses, estrogen-receptor positive or progesterone-receptor positive (ER+/PR+) tumors were associated with higher ambient levels of acrylamide, benzidine, carbon tetrachloride, ethylidene dichloride, and vinyl chloride, while ER-/PR- tumors were associated with higher ambient levels of benzene. Interesting results for different compounds were observed within certain subsets of the population. CONCLUSION: While our initial models yielded several elevated risk estimates, after adjusting for multiple comparisons and breast cancer risk factors, most hazard ratios were no longer statistically significant. Our subset analyses, however, suggest that elevated risk may be associated with some compounds for certain subgroups of interest. A summary variable for all 24 MGCs did not offer any advantage over the models for individual compounds. Results must be interpreted cautiously, as estimated exposure was limited to modeled annual average ambient air concentrations, and could not account for other sources or routes other than inhalation.

Associations of mortality with long-term exposures to fine and ultrafine particles, species and sources: results from the California Teachers Study Cohort.

BACKGROUND: Although several cohort studies report associations between chronic exposure to fine particles (PM2.5) and mortality, few have studied the effects of chronic exposure to ultrafine (UF) particles. In addition, few studies have estimated the effects of the constituents of either PM2.5 or UF particles. METHODS: We used a statewide cohort of > 100,000 women from the California Teachers Study who were followed from 2001 through 2007. Exposure data at the residential level were provided by a chemical transport model that computed pollutant concentrations from > 900 sources in California. Besides particle mass, monthly concentrations of 11 species and 8 sources or primary particles were generated at 4-km grids. We used a Cox proportional hazards model to estimate the association between the pollutants and all-cause, cardiovascular, ischemic heart disease (IHD), and respiratory mortality. RESULTS: We observed statistically significant (p < 0.05) associations of IHD with PM2.5 mass, nitrate, elemental carbon (EC), copper (Cu), and secondary organics and the sources gas- and diesel-fueled vehicles, meat cooking, and high-sulfur fuel combustion. The hazard ratio estimate of 1.19 (95% CI: 1.08, 1.31) for IHD in association with a 10-µg/m3 increase in PM2.5 is consistent with findings from the American Cancer Society cohort. We also observed significant positive associations between IHD and several UF components including EC, Cu, metals, and mobile sources. CONCLUSIONS: Using an emissions-based model with a 4-km spatial scale, we observed significant positive associations between IHD mortality and both fine and ultrafine particle species and sources. Our results suggest that the exposure model effectively measured local exposures and facilitated the examination of the relative toxicity of particle species.

Disaggregating data on Asian American and Pacific Islander women to provide new insights on potential exposures to hazardous air pollutants in California.

BACKGROUND: The Asian American and Pacific Islander (AAPI) population is heterogeneous and rapidly growing in the United States, with a high proportion concentrated in California. Although traditionally assumed to have lower rates of breast cancer than non-Hispanic white women, recent studies have suggested considerable variation in incidence by AAPI ethnic group, with rates in some exceeding those in non-Hispanic whites. The potential role of environmental toxicants has not been well explored and may provide insights into these patterns. METHODS: We created an exposure potential index (EPI) score for 24 hazardous air pollutants modeled by the U.S. Environmental Protection Agency National-Scale Air Toxics Assessment considered to be mammary gland carcinogens, and compared values at the census tract level for "geographically concentrated" AAPI groups throughout the State. "Geographically concentrated" populations were defined as census tracts with at least 100 individuals from a specified racial/ethnic population as enumerated by the 2000 Census. RESULTS: Although EPI scores differed little between census tracts with aggregated AAPI (mean EPI = 0.53) and non-Hispanic white women (mean EPI = 0.63), there was substantial variation between tracts for disaggregated AAPI groups, with notably higher EPI scores for tracts enumerated for Korean or Japanese women (mean EPI of 0.78 and 0.77, respectively) compared with other AAPI groups. CONCLUSIONS: Our findings underscore the importance of disaggregating data for the heterogeneous AAPI population to identify differences in potential environmental exposures across groups. IMPACT: Future cancer etiology studies should examine environmental exposure differences within and across groups for the diverse AAPI population.