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Background: Exposure to fine particulate (PM2.5) air pollution is associated with increased cardiovascular disease (CVD), but less is known about its specific components, such as metals originating from non-tailpipe emissions. We investigated the associations of long-term exposure to metal components [iron (Fe) and copper (Cu)] in PM2.5 with CVD incidence.Methods: We conducted a population-based cohort study in Toronto, Canada. Exposures to Fe and Cu in PM2.5 and their combined impact on the concentration of reactive oxygen species (ROS) in lung fluid were estimated using land use regression models. Incidence of acute myocardial infarction (AMI), congestive heart failure (CHF) and CVD death was ascertained using health administrative datasets. We used mixed-effects Cox regression models to examine the associations between the exposures and health outcomes. A series of sensitivity analyses were conducted, including indirect adjustment for individual-level cardiovascular risk factors (e.g. smoking), and adjustment for PM2.5 and nitrogen dioxide (NO2).Results: In single-pollutant models, we found positive associations between the three exposures and all three outcomes, with the strongest associations detected for the estimated ROS. The associations of AMI and CHF were sensitive to indirect adjustment, but remained robust for CVD death in all sensitivity analyses. In multi-pollutant models, the associations of the three exposures generally remained unaltered. Interestingly, adjustment for ROS did not substantially change the associations between PM2.5 and CVD, but attenuated the associations of NO2.Conclusions: Long-term exposure to Fe and Cu in PM2.5 and their combined impact on ROS were consistently associated with increased CVD death. [ABSTRACT FROM AUTHOR]

Background: Disease management programs (DMPs) that use multidisciplinary teams and specialized clinics reduce hospital admissions and improve quality of life and functional status. Evaluations of cardiac DMPs delivered by home health nurses are required. Methods: Between August 1999 and August 2000 we identified consecutive patients admitted to hospital with elevated cardiac enzymes. Patients who agreed were randomly assigned to participate in a DMP or to receive usual care. The DMP included 6 home visits by a cardiac-trained nurse, a standardized nurses' checklist, referral criteria for specialty care, communication with the family physician and patient education. We measured readmission days per 1000 follow-up days for angina, congestive heart failure (CHF) and chronic obstructive pulmonary disease (COPD); all-cause readmission days; and provincial claims for emergency department visits, physician visits, diagnostic or therapeutic services and laboratory services. Results: We screened 715 consecutive patients admitted with elevated cardiac markers between August 1999 and August 2000. Of those screened 71 DMP and 75 usual care patients met the diagnostic criteria for myocardial infarction, were eligible for visits from a home health nurse and consented to participate in the study. Readmission days for angina, CHF and COPD per 1000 follow-up days were significantly higher for usual care patients than for DMP patients (incidence density ratio [IDR] = 1.59, 95% confidence interval [CI] 1.27-2.00, p < 0.001). All-cause readmission days per 1000 follow-up days were significantly higher for usual care patients than for DMP patients (IDR = 1.53, 95% CI 1.37-1.71, p< 0.001). The difference in emergency department encounters per... [ABSTRACT FROM AUTHOR]