Background Adverse effects of air pollution on cardiovascular disease (CVD) mortality are well established. There are comparatively fewer studies in Europe, and in the UK particularly, than in North America. We examined associations in two British cohorts with > 25 years of follow-up. Methods Annual average NO2, SO2and black smoke (BS) air pollution exposure estimates for 1991 were obtained from land use regression models using contemporaneous monitoring data. From the European Study of Cohorts and Air Pollution (ESCAPE), air pollution estimates in 2010–11 were obtained for NO2, NOx, PM10, PMcoarseand PM2.5. The exposure estimates were assigned to place of residence 1989 for participants in a national birth cohort born in 1946, the MRC National Study of Health and Development (NSHD), and an adult multi-ethnic London cohort, Southall and Brent Revisited (SABRE) recruited 1988–91. The combined median follow-up was 26 years. Single-pollutant competing risk models were employed, adjusting for individual risk factors. Results Elevated non-significant hazard ratios for CVD mortality were seen with 1991 BS and SO2and with ESCAPE PM10and PM2.5in fully adjusted linear models. Per 10 μg/m3increase HRs were 1.11 [95% CI: 0.76–1.61] for BS, 1.05 [95% CI: 0.91–1.22] for SO2, 1.16 [95% CI: 0.70–1.92] for PM10and 1.30 [95% CI: 0.39–4.34] for PM2.5, with largest effects seen in the fourth quartile of BS and PM2.5compared to the first with HR 1.24 [95% CI: 0.91–1.61] and 1.21 [95% CI: 0.88–1.66] respectively. There were no consistent associations with other ESCAPE pollutants, or with 1991 NO2. Modelling using Cox regression led to similar results. Conclusion Our results support a detrimental long-term effect for air pollutants on cardiovascular mortality.
Bibliographical noteFunding Information:
The SABRE Study was funded at baseline by the UK Medical Research Council, Diabetes UK and the British Heart Foundation, and at follow-up by the Wellcome Trust and British Heart Foundation. The Medical Research Council provides core funding for the MRC National Survey of Health and Development and supports RH (MC_UU_12019/1, MC_UU_12019/2). The first author was supported by the British Heart Foundation for this work.
© 2016 The Authors
- Environmental epidemiology
- Follow-up studies
- Long-term exposure
- Particulate matter