Association between heatwave exposure and rapid kidney function decline: a longitudinal cohort study from CHARLS

Area of Science:

• Environmental Health
• Nephrology
• Gerontology

Background:

• Renal disease poses a substantial global health and economic burden.
• Rising global temperatures and heatwaves are projected to disproportionately affect kidney health, particularly in older adults.

Purpose of the Study:

• To investigate the association between heatwave exposure and the risk of rapid kidney function decline in older adults.
• To identify vulnerable populations susceptible to heat-related kidney damage.

Main Methods:

• Utilized data from the China Health and Retirement Longitudinal Study (6450 participants, 2011-2015).
• Assessed individual daily heatwave exposure using 12 definitions (thresholds and durations).
• Measured kidney function via estimated glomerular filtration rate (eGFR) and defined rapid decline as eGFR decrease ≥ 3 mL/min/1.73 m²/year. Employed multivariate logistic regression.

Main Results:

• Increased exposure to moderate to high-intensity heatwaves was significantly linked to a higher risk of rapid kidney function decline.
• Associations remained robust after adjusting for demographic, medical, and lifestyle factors.
• Males, urban residents, smokers, and alcohol consumers were identified as vulnerable groups.

Conclusions:

• Elevated heatwave exposure is associated with an increased risk of accelerated kidney function decline in the elderly population.
• Findings underscore the critical need for targeted public health interventions to protect older adults from heat-related kidney damage.