Improved estimation of wildfire smoke exposures: Characterizing kidney disease risk - PROJECT SUMMARY/ABSTRACT This application proposes improved exposure estimation approaches to wildfire smoke impacts to conduct better epidemiologic assessment of kidney health risks, in the setting of a career development proposal. Dr. Jianzhao Bi will create novel wildfire-derived PM2.5 (particulate matter < 2.5 µm in aerodynamic diameter) exposure estimates with spatiotemporally complete coverage to characterize the effects of wildfire PM2.5 exposure on individuals with or at risk of chronic kidney disease (CKD) and end-stage kidney disease (ESKD), a large population extremely vulnerable to natural disasters, including wildfire smoke. Under the mentorship of Dr. Joel Kaufman, this training and research plan will build upon Dr. Bi’s expertise in air pollution exposure and epidemiology and prepare him for a career studying advanced analytic methods to understand environmental exposures and their application in epidemiologic research. During the K99 phase, Dr. Bi will use didactic instruction and independent study to gain additional training in 1) advanced data analysis and statistical methods for “big data”, 2) analysis of PM2.5 speciation related to wildfire smoke, 3) epidemiologic analysis for long-term air pollution exposure, 4) nephrotoxicity and mechanisms of PM2.5, and 5) electronic health data processing. This training will provide Dr. Bi with interdisciplinary skills and knowledge as he moves toward an independent research career in advanced environmental exposure and epidemiologic analyses. Dr. Bi’s research in the K99 phase aims to 1) develop innovative statistical prediction models to accurately separate wildfire PM2.5 from total PM2.5 and 2) incorporate novel quantitative satellite and dense low-cost monitoring data into wildfire PM2.5 prediction. Dr. Bi’s wildfire PM2.5 models will require substantially fewer computational resources than chemical transport models (CTMs), while producing exposure estimates expected to be more accurate than the estimates derived by CTM and current statistical methods. During the R00 phase, Dr. Bi’s research focuses on assessing 1) chronic effects of multi-year wildfire PM2.5 exposure on individuals with or at risk of CKD and 2) acute effects of multi-day wildfire PM2.5 exposure on ESKD patients receiving in-center hemodialysis (HD). His epidemiologic analyses will rely on the Center for Kidney Disease Research, Education and Hope (CURE-CKD) registry with individuals from inpatient, outpatient, and ambulatory settings following strict guideline-based CKD or at risk of CKD criteria in the western U.S., and the United States Renal Data System (USRDS) with patient-level demographics and dialysis/medical/mortality records on nearly all U.S. patients with ESKD receiving HD (with a focus on the western U.S.). The R00 phase also examines effect modification by key variables and differences in toxicity between wildfire and non-wildfire PM2.5. Dr. Bi’s epidemiologic studies will allow crucial new insights into the concentration-response relationships between wildfire PM2.5 exposure and its effects on the vulnerable kidney disease population. Better understanding the health impacts of wildfire smoke will facilitate more effective smoke management decisions and policies, and in turn reduce the associated substantial health costs.
