Impact of air pollution on hospital admissions in Southwestern Ontario, Canada: Generating hypotheses in sentinel high-exposure places

<p>Abstract</p> <p>Background</p> <p>Southwestern Ontario (SWO) in Canada has been known as a 'hot spot' in terms of environmental exposure and potential effects. We chose to study 3 major cities in SWO in this paper. We compared age-standardized hospital admission ratios of Sarnia and Windsor to London, and to generate hypotheses about potential pollutant-induced health effects in the 'Chemical Valley', Sarnia.</p> <p>Methods</p> <p>The number of daily hospital admissions was obtained from all hospitals in London, Windsor and Sarnia from January 1, 1996 to December 31, 2000. We used indirect age adjustment method to obtain standardized admissions ratios for males and females and we chose London as the reference population. This process of adjustment was to apply the age-specific admission rates of London to the population of Sarnia and Windsor in order to yield expected admissions. The observed number of admissions was then compared to the expected admissions in terms of a ratio. These standardized admissions ratios and their corresponding confidence intervals were calculated for Sarnia and Windsor.</p> <p>Results</p> <p>Our findings showed that Sarnia and Windsor had significantly higher age-adjusted hospital admissions rates compared to London. This finding was true for all admissions, and especially pronounced for cardiovascular and respiratory admissions. For example, in 1996, the observed number of admissions in Sarnia was 3.11 (CI: 2.80, 3.44) times for females and 2.83 (CI: 2.54, 3.14) times for males as would be expected by using London's admission rates.</p> <p>Conclusion</p> <p>Since hospital admissions rates were significantly higher in 'Chemical Valley' as compared to both London and Windsor, we hypothesize that these higher rates are pollution related. A critical look at the way ambient air quality and other pollutants are monitored in this area is warranted. Further epidemiological research is needed to verify our preliminary indications of harmful effects in people living in 'Chemical Valley'.</p

Breast Cancer Care in California and Ontario: Primary Care Protections Greatest Among the Most Socioeconomically Vulnerable Women Living in the Most Underserved Places

Background: Better health care among Canada’s socioeconomically vulnerable versus America’s has not been fully explained. We examined the effects of poverty, health insurance and the supply of primary care physicians on breast cancer care. Methods: We analyzed breast cancer data in Ontario (n = 950) and California (n = 6300) between 1996 and 2000 and followed until 2014. We obtained socioeconomic data from censuses, oversampling the poor. We obtained data on the supply of physicians, primary care and specialists. The optimal care criterion was being diagnosed early with node negative disease and received breast conserving surgery followed by adjuvant radiation therapy. Results: Women in Ontario received more optimal care in communities well supplied by primary care physicians. They were particularly advantaged in the most disadvantaged places: high poverty neighborhoods (rate ratio = 1.65) and communities lacking specialist physicians (rate ratio = 1.33). Canadian advantages were explained by better health insurance coverage and greater primary care access. Conclusions: Policy makers ought to ensure that the newly insured are adequately insured. The Medicaid program should be expanded, as intended, across all 50 states. Strengthening America’s system of primary care will probably be the best way to ensure that the Affordable Care Act’s full benefits are realized

Health insurance mediation of the Mexican American non-Hispanic white disparity on early breast cancer diagnosis

We examined health insurance mediation of the Mexican American (MA) non-Hispanic white (NHW) disparity on early breast cancer diagnosis. Based on social capital and barrio advantage theories, we hypothesized a 3-way ethnicity by poverty by health insurance interaction, that is, that 2-way poverty by health insurance interaction effects would differ between ethnic groups. We secondarily analyzed registry data for 303 MA and 3,611 NHW women diagnosed with breast cancer between 1996 and 2000 who were originally followed until 2011. Predictors of early, node negative (NN) disease at diagnosis were analyzed. Socioeconomic data were obtained from the 2000 census to categorize neighborhood poverty: high (30% or more of the census tract households were poor), middle (5% to 29% poor) and low (less than 5% poor). Barrios were neighborhoods where 50% or more of the residents were MA. Primary health insurers were Medicaid, Medicare, private or none. MA women were 13% less likely to be diagnosed early with NN disease (RR = 0.87), but this MA-NHW disparity was completely mediated by the main and interacting effects of health insurance. Advantages of health insurance were largest in low poverty neighborhoods among NHW women (RR = 1.20) while among MA women they were, paradoxically, largest in high poverty, MA barrios (RR = 1.45). Advantages of being privately insured were observed for all. Medicare seemed additionally instrumental for NHW women and Medicaid for MA women. These findings are consistent with the theory that more facilitative social and economic capital is available to MA women in barrios and to NHW women in more affluent neighborhoods. It is there that each respective group of women is probably best able to absorb the indirect and direct, but uncovered, costs of breast cancer screening and diagnosis

The supply of physicians and care for breast cancer in Ontario and California, 1998 to 2006

INTRODUCTION: We examined the differential effects of the supply of physicians on care for breast cancer in Ontario and California. We then used criteria for optimum care for breast cancer to estimate the regional needs for the supply of physicians. METHODS: Ontario and California registries provided 951 and 984 instances of breast cancer diagnosed between 1998 and 2000 and followed until 2006. These cohorts were joined with the supply of county-level primary care physicians (PCPs) and specialists in cancer care and compared on care for breast cancer. RESULTS: Significant protective PCP thresholds (7.75 to = 8.25 PCPs per 10 000 inhabitants) were observed for breast cancer diagnosis (odds ratio [OR] 1.62), receipt of adjuvant radiotherapy (OR 1.64) and 5-year survival (OR 1.87) in Ontario, but not in California. The number of physicians seemed adequate to optimize care for breast cancer across diverse places in California and in most Ontario locations. However, there was an estimated need for 550 more PCPs and 200 more obstetrician-gynecologists in Ontario\u27s rural and small urban areas. We estimated gross physician surpluses for Ontario\u27s 2 largest cities. CONCLUSION: Policies are needed to functionally redistribute primary care and specialist physicians. Merely increasing the supply of physicians is unlikely to positively affect the health of Ontarians

Gender differences on the interacting effects of marital status and health insurance on long-term colon cancer survival in California, 1995-2014

Objectives. Long-term colon cancer survival is not well explained by main effects. We explored the interaction of age, gender, marital status, health insurance and poverty on 10-year colon cancer survival. Methods. California registry data were analyzed for 5,776 people diagnosed from 1995 to 2000; followed until 2014. Census data classified neighborhood poverty. We tested interactions with regressions and described them with standardized rates and rate ratios (RR). Results. The 5-way interaction was significant, suggesting larger 4-way disadvantages among non-Medicare-eligible people. A significant 4-way interaction was a 3-way interaction in non-high poverty neighborhoods only. Private insurance was protective for unmarried men (RR = 1.60) but not women, while it was protective for married women (RR = 1.22) but not men. This pattern seemed explained by lower-incomes of certain groups of unmarried women and married men and more prevalent underinsuring of unmarried men. Conclusions. Structural inequities related to the institutions of marriage and health care seem to affect women and men quite differently. Policy makers ought to be cognizant of such structural imbalances as future reforms of American health care are considered

Disparities among Minority Women with Breast Cancer Living in Impoverished Areas of California

Background: Interaction effects of poverty and health care insurance coverage on overall survival rates of breast cancer among women of color and non-Hispanic white women were explored. Methods: We analyzed California registry data for 2,024 women of color (black, Hispanic, Asian, Pacific Islander, American Indian, or other ethnicity) and 4,276 non-Hispanic white women (Anglo-European ancestries and no Hispanic-Latin ethnic backgrounds) diagnosed with breast cancer between the years 1996 and 2000 who were then followed until 2011. The 2000 US census categorized rates of neighborhood poverty. Health care insurance coverage was either private, Medicare, Medicaid, or none. Cox regression was used to model rates of survival. Results: A 3-way interaction between ethnicity, health care insurance coverage, and poverty was observed. Women of color inadequately insured and living in poor or near-poor neighborhoods in California were the most disadvantaged. Women of color adequately insured and who lived in such neighborhoods in California were also disadvantaged. The incomes of such women of color were typically lower than the incomes of non-Hispanic white women. Conclusions: Women of color with or without insurance coverage are disadvantaged in poor and near-poor neighborhoods of California. Such women may be less able to bare the indirect, direct, or uncovered costs of health care for breast cancer treatment

Colon cancer care of Hispanic people in California: Paradoxical barrio protections seem greatest among vulnerable populations

Background: We examined paradoxical and barrio advantaging effects on cancer care among socioeconomically vulnerable Hispanic people in California. Methods: We secondarily analyzed a colon cancer cohort of 3,877 non-Hispanic white (NHW) and 735 Hispanic people treated between 1995 and 2005. A third of the cohort was selected from high poverty neighborhoods. Hispanic enclaves and Mexican American (MA) barrios were neighborhoods where 40% or more of the residents were Hispanic or MA. Key analyses were restricted to high poverty neighborhoods. Results: Hispanic people were more likely to receive chemotherapy (RR=1.18), especially men in Hispanic enclaves (RR=1.33) who were also advantaged on survival (RR=1.20). A survival advantage was also suggested among MA men who resided in barrios (RR=1.80). Conclusions: The findings were supportive of Hispanic paradox and MA barrio advantage theories. They further suggested that such advantages are greater for men, perhaps due to their greater spousal and extended familial support

Breast Cancer among Women Living in Poverty: Better Care in Canada than in the United States

This historical study estimated the protective effects of a universally accessible, single-payer health care system versus a multipayer system that leaves many uninsured or underinsured by comparing breast cancer care of women living in high-poverty neighborhoods in Ontario and California between 1996 and 2011. Women in Canada experienced better care, particularly as compared with women who were inadequately insured in the United States. Women in Canada were diagnosed earlier (rate ratio [RR] = 1.12) and enjoyed better access to breast conserving surgery (RR = 1.48), radiation (RR = 1.60), and hormone therapies (RR = 1.78). Women living in high-poverty Canadian neighborhoods even experienced shorter waits for surgery (RR = 0.58) and radiation therapy (RR = 0.44) than did such women in the United States. Consequently, women in Canada were much more likely to survive longer. Regression analyses indicated that health insurance could explain most of the better care and better outcomes in Canada. Over this study’s 15-year time frame 31,500 late diagnoses, 94,500 suboptimum treatment plans, and 103,500 early deaths were estimated in high-poverty U.S. neighborhoods due to relatively inadequate health insurance coverage. Implications for social work practice, including advocacy for future reforms of U.S. health care, are discussed

Effects of socioeconomic status on colon cancer treatment accessibility and survival in Toronto, Ontario, and San Francisco, California, 1996-2006

OBJECTIVES: We examined the differential effects of socioeconomic status on colon cancer care and survival in Toronto, Ontario, Canada, and San Francisco, California. METHODS: We analyzed registry data for colon cancer patients from Ontario (n = 930) and California (n = 1014), diagnosed between 1996 and 2000 and followed until 2006, on stage, surgery, adjuvant chemotherapy, and survival. We obtained socioeconomic data for individuals\u27 residences from population censuses. RESULTS: Income was directly associated with lymph node evaluation, chemotherapy, and survival in San Francisco but not in Toronto. High-income persons had better survival rates in San Francisco than in Toronto. After adjustment for stage, survival was better for low-income residents of Toronto than for those of San Francisco. Middle- to low-income patients were more likely to receive indicated chemotherapy in Toronto than in San Francisco. CONCLUSIONS: Socioeconomic factors appear to mediate colon cancer care in urban areas of the United States but not in Canada. Improvements are needed in screening, diagnostic investigations, and treatment access among low-income Americans