Study finds link between climate change and increases in kidney stone occurrence

In a recent study, investigators found that rising global temperatures will cause significant increases in kidney stone occurrence among Earth’s population.¹

Results showed that the projected proportion of heat-related kidney stone disease was 0.62% and 0.77% in the 2025-2029 period, vs 2.2% and 3.9% in the 2085-2089 period, for representative concentration pathways (RCPs) 4.5 and 8.5, respectively.

Gregory E. Tasian, MD, MSc, MSCE

“With climate change, we don’t often talk about the impact on human health, particularly when it comes to children, but a warming planet will have significant effects on human health,” explained senior author Gregory E. Tasian, MD, MSc, MSCE, an attending pediatric urologist in the Division of Urology at Children's Hospital of Philadelphia, in a news release.² “As pediatric researchers, we have a duty to explore the burden of climate change on human health, as children of today will be living this reality in the future.”

First, to examine the correlation between state-wide daily mean wet-bulb temperatures (WBT) and kidney stone disease presentation in South Carolina, Tasian and co-authors performed an aggregated case-crossover study. The study analyzed data (1997-2014) from the NASA Land Data Assimilation Systems.

An additional study was performed to project the number of heat-related kidney stone disease presentations and associated cost to the year 2089. This was based on the projected daily WBT under 2 different climate change scenarios: RCP 4.5 represented an “intermediate” future with lower greenhouse gas emissions, and RCP 8.5 represented a more extreme future with higher greenhouse gas emissions.

“Our analysis is a model to conceptualize how the burden of kidney stone disease is expected to progress with climate change, and also how mitigations to greenhouse gas emissions can offset some of this burden,” said first author Jason Kaufman, a fourth-year medical student at the University of Pennsylvania Perelman School of Medicine, Philadelphia.

Findings of the first study suggested a mean temperature increase projection of 2.3°C per 5-year period from 2010-2014 to 2085-2089 for RCP 4.5. Conversely, there was a mean temperature increase projection of 3.6°C over the same time frame for RCP 8.5. The number of days projected to exceed the historic maximum daily mean from 1997-2014 (26°C) were also expected to increase over time, especially in RCP 8.5.

Findings of the second study suggested an increase in heat-related kidney stone presentations by 5938 (95% CI 3730-9418) and 10,431 (95% CI 6724-15,581) for RCP 4.5 and 8.5, respectively. There was no evidence of a plateau at higher temperatures. Additionally, the total cost associate with these kidney stone presentations were $56,565,091 and $99,365,184 from 2025-2089 for RCP 4.5 and 8.5, respectively.

Limitations of this study included uncertain association assumptions about temperature and kidney stone presentations and the consideration of only 1 geographic area, among others.

“While it’s impossible to predict with certainty how future policies will slow or hasten greenhouse gas emission and anthropogenic climate change, and to know exactly what future daily temperatures will be, our analysis suggests that a warming planet will likely cause an increased burden of kidney stone disease on health care systems,” concluded Tasian.

References

1. Kaufman J, Vicedo-Cabrera AM, Tam V, et al. The impact of heat on kidney stone presentations in South Carolina under two climate change scenarios. Sci Rep. 2022;12(1):369 doi:10.1038/s41598-021-04251-2

2. Study shows climate change will lead to increase in kidney stones. News release. Children’s Hospital of Philadhelpia. January 5, 2022. Accessed January 13, 2022. https://www.newswise.com/articles/study-shows-climate-change-will-lead-to-increase-in-kidney-stones?sc=mwhr&xy=10016681