A Comparison of Short-term and Long-term Air Pollution Exposure Associations with Mortality in Two Cohorts in Scotland

作者：Beverland Iain J^*; Cohen Geoffrey R; Heal Mathew R; Carder Melanie; Yap Christina; Robertson Chris; Hart Carole L; Agius Raymond M

来源：Environmental Health Perspectives, 2012, 120(9): 1280-1285.

DOI：10.1289/ehp.1104509

• air
• associations
• cohort
• exposure-mortality
• long term
• pollution
• short term
• time-series

BACKGROUND: Air pollution-mortality risk estimates are generally larger at longer-term, compared with short-term, exposure time scales. %26lt;br%26gt;OBJECTIVE: We compared associations between short-term exposure to black smoke (BS) and mortality with long-term exposure-mortality associations in cohort participants and with short-term exposure-mortality associations in the general population from which the cohorts were selected. %26lt;br%26gt;METHODS: We assessed short-to-medium term exposure-mortality associations in the Renfrew Paisley and Collaborative cohorts (using nested case-control data sets), and compared them with long-term exposure-mortality associations (using a multilevel spatiotemporal exposure model and survival analyses) and short-to-medium term exposure-mortality associations in the general population (using time-series analyses). %26lt;br%26gt;RESULTS: For the Renfrew-Paisley cohort (15,331 participants), BS exposure-mortality associations were observed in nested case-control analyses that accounted for spatial variations in pollution exposure and individual-level risk factors. These cohort-based associations were consistently greater than associations estimated in time-series analyses using a single monitoring site to represent general population exposure [e.g., 1.8% [95% confidence interval (CI): 0.1, 3.4%] vs. 0.2% (95% CI: 0.0, 0.4%) increases in mortality associated with 10-mu g/m(3) increases in 3-day lag BS, respectively]. Exposure-mortality associations were of larger magnitude for longer exposure periods [e.g., 3.4% (95% CI: -0.7, 7.7%) and 0.9% (95% CI: 0.3, 1.5%) increases in all-cause mortality associated with 10-mu g/m(3) increases in 31-day BS in case-control and time-series analyses, respectively; and 10% (95% CI: 4, 17%) increase in all-cause mortality associated with a 10-mu g/m(3) increase in geometic mean BS for 1970-1979, in survival analysis]. %26lt;br%26gt;CONCLUSIONS: After adjusting for individual-level exposure and potential confounders, short-term exposure mortality associations in cohort participants were of greater magnitude than in comparable general population time-series study analyses. However, short-term exposure-mortality associations were substantially lower than equivalent long-term associations, which is consistent with the possibility of larger, more persistent cumulative effects from long-term exposures.

• 出版日期2012-9