Cardiopulmonary Mortality and Fine Particulate Air Pollution by Species and Source in a National U.S. Cohort.

The purpose of this study was to estimate cardiopulmonary mortality associations for long-term exposure to PM2.5 species and sources (i.e., components) within the U.S. National Health Interview Survey cohort. Exposures were estimated through a chemical transport model for six species (i.e., elemental carbon (EC), primary organic aerosols (POA), secondary organic aerosols (SOA), sulfate (SO4), ammonium (NH4), nitrate (NO3)) and five sources of PM2.5 (i.e., vehicles, electricity-generating units (EGU), non-EGU industrial sources, biogenic sources (bio), "other" sources). In single-pollutant models, we found positive, significant (p < 0.05) mortality associations for all components, except POA. After adjusting for remaining PM2.5 (total PM2.5 minus component), we found significant mortality associations for EC (hazard ratio (HR) = 1.36; 95% CI [1.12, 1.64]), SOA (HR = 1.11; 95% CI [1.05, 1.17]), and vehicle sources (HR = 1.06; 95% CI [1.03, 1.10]). HRs for EC, SOA, and vehicle sources were significantly larger in comparison to those for remaining PM2.5 (per unit µg/m3). Our findings suggest that cardiopulmonary mortality associations vary by species and source, with evidence that EC, SOA, and vehicle sources are important contributors to the PM2.5 mortality relationship. With further validation, these findings could facilitate targeted pollution regulations that more efficiently reduce air pollution mortality.

Radiation modality use and cardiopulmonary mortality risk in elderly patients with esophageal cancer.

BACKGROUND: It is currently unclear whether the superior normal organ-sparing effect of intensity-modulated radiotherapy (IMRT) compared with 3-dimensional radiotherapy (3D) has a clinical impact on survival and cardiopulmonary mortality in patients with esophageal cancer (EC). METHODS: The authors identified 2553 patients aged > 65 years from the Surveillance, Epidemiology, and End Results (SEER)-Medicare and Texas Cancer Registry-Medicare databases who had nonmetastatic EC diagnosed between 2002 and 2009 and were treated with either 3D (2240 patients) or IMRT (313 patients) within 6 months of diagnosis. The outcomes of the 2 cohorts were compared using inverse probability of treatment weighting adjustment. RESULTS: Except for marital status, year of diagnosis, and SEER region, both radiation cohorts were well balanced with regard to various patient, tumor, and treatment characteristics, including the use of IMRT versus 3D in urban/metropolitan or rural areas. IMRT use increased from 2.6% in 2002 to 30% in 2009, whereas the use of 3D decreased from 97.4% in 2002 to 70% in 2009. On propensity score inverse probability of treatment weighting-adjusted multivariate analysis, IMRT was not found to be associated with EC-specific mortality (hazard ratio [HR], 0.93; 95% confidence interval [95% CI], 0.80-1.10) or pulmonary mortality (HR, 1.11; 95% CI, 0.37-3.36), but was significantly associated with lower all-cause mortality (HR, 0.83; 95% CI, 0.72-0.95), cardiac mortality (HR, 0.18; 95% CI, 0.06-0.54), and other-cause mortality (HR, 0.54; 95% CI, 0.35-0.84). Similar associations were noted after adjusting for the type of chemotherapy, physician experience, and sensitivity analysis removing hybrid radiation claims. CONCLUSIONS: In this population-based analysis, the use of IMRT was found to be significantly associated with lower all-cause mortality, cardiac mortality, and other-cause mortality in patients with EC.

Ambient PM2.5 and cardiopulmonary mortality in the oldest-old people in China: A national time-stratified case-crossover study.

BACKGROUND: Evidence on the associations of fine particulate matter (PM2.5) with cardiopulmonary mortality in the oldest-old (aged 80+ years) people remains limited. METHODS: We conducted a time-stratified case-crossover study of 1,475,459 deaths from cardiopulmonary diseases in China to estimate the associations between short-term exposure to ambient PM2.5 and cardiopulmonary mortality among the oldest-old people. FINDINGS: Each 10 µg/m3 increase in PM2.5 concentration (6-day moving average [lag05]) was associated with higher mortality from cardiopulmonary diseases (excess risks [ERs] = 1.69%, 95% confidence interval [CI]: 1.54%, 1.84%), cardiovascular diseases (ER = 1.72%, 95% CI: 1.54%, 1.90%), and respiratory diseases (ER = 1.62%, 95% CI: 1.33%, 1.91%). Compared to the other groups, females (ER = 1.94%, 95% CI: 1.73%, 2.15%) (p for difference test = 0.043) and those aged 95-99 years (ER = 2.31%, 95% CI: 1.61%, 3.02%) (aged 80-85 years old was the reference, p for difference test = 0.770) presented greater mortality risks. We found 14 specific cardiopulmonary causes associated with PM2.5, out of which emphysema (ER = 3.20%, 95% CI: 1.57%, 4.86%) had the largest association. Out of the total deaths, 6.27% (attributable fraction [AF], 95% CI: 5.72%, 6.82%) were ascribed to short-term PM2.5 exposure. CONCLUSIONS: This study provides evidence of PM2.5-induced cardiopulmonary mortality and calls for targeted prevention actions for the oldest-old people. FUNDING: This work was supported by the National Key Research and Development Program of China, the National Natural Science Foundation of China, the Foreign Expert Program of the Ministry of Science and Technology, the Natural Science Foundation of Guangdong, China, and the Science and Technology Program of Guangzhou.

The mediating role of lung function on air pollution-induced cardiopulmonary mortality in elderly women: The SALIA cohort study with 22-year mortality follow-up.

BACKGROUND: Air pollution exposure is associated with reduced lung function and increased cardio-pulmonary mortality (CPM). OBJECTIVES: We analyzed the potential mediating effect of reduced lung function on the association between air pollution exposure and CPM. METHODS: We used data from the German SALIA cohort including 2527 elderly women (aged 51-56 years at baseline 1985-1994) with 22-year follow-up to CPM. Exposures to PM10, PM2.5, PM2.5 absorbance, NO2 and NOx were assessed by land-use regression modelling and back-extrapolated to estimate exposures at baseline. Lung function (FVC, FEV1) was measured by spirometry and transformed to GLI z-scores. Adjusted Cox proportional hazards and causal proportional hazards mediation analysis models were fitted. RESULTS: The survival analysis showed that reduced lung function (z-scores of FVC or FEV1 below 5% predicted) reflected significantly lower survival probability from CPM (p < 0.0001). Longterm exposures to NOx and NO2 were associated with increased risks of CPM (eg. HR = 1.215; 95%CI: 1.017-1.452 for IQR increase in NOx and HR = 1.209; 95%CI: 1.011-1.445 for IQR increase in NO2) after adjusting for reduced lung function and additional covariates. The associations of PM2.5 absorbance and CPM remained significant in models adjusted for FEV1/FVC, but the associations with PM10 and PM2.5 were not significant. The mediation analysis showed significant indirect effects of NO2 and NOx on CPM mediated through reduced FEV1 and FVC. The largest indirect effects were found for exposures to NO2 (HR = 1.037; 95%CI: 1.005-1.070) and NOx (HR = 1.028; 95%CI: 1.004-1.052) mediated through reduced FVC. The mediated proportion effect ranged from 13.9% to 19.6% in fully adjusted models. DISCUSSION: This study provides insights into the mechanism of reduced lung function in association between long-term air pollution exposure and CPM. The mediated effect was substantial for exposure to nitrogen oxides (NOx and NO2), but less pronounced for PM10 and PM2.5.