Ran J, Yang A, Sun S, et al. - Among participants of the Elderly Health Service Cohort, researchers estimated renal failure (RF) mortality in relation to long-term exposure to fine particulate matter (PM_2.5) in Hong Kong from 1998 to 2010. Using a satellite-based spatiotemporal model, they estimated PM_2.5 level at the residential address of each participant. Data analyses including 61,447 participants were performed. A follow-up of 10 years revealed 443 RF deaths. The hazard ratios of RF mortality for an interquartile-range rise in PM_2.5 levels (3.22 μg/m³) were estimated to be 1.23 and 1.42 among all cohort participants and among patients with chronic kidney disease, respectively. Based on the findings, it was concluded that long-term exposure to atmospheric PM_2.5 might represent a crucial risk factor of RF mortality in the elderly, particularly in individuals with existing renal diseases.