Household Fuel Use and Kidney Disease-Related Mortality: The Golestan Cohort Study.

BACKGROUND

A large proportion of the global population uses solid fuels for household purposes, and limited evidence from previous studies suggests that it might be associated with reduced renal function.

OBJECTIVES

To investigate the association between household use of different types of fuels and kidney disease-related mortality.

METHODS

We analyzed data from the Golestan Cohort Study, a population-based prospective cohort study conducted in northeastern Iran, with 50 045 individuals aged 40-75 years enrolled in the period 2004-2008 and followed through April 2023. Information about household fuel use was collected using validated questionnaires. We estimated adjusted hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) using Cox proportional hazards models. The outcome of interest was death due to any kidney disease, excluding kidney cancer (ICD-10 codes: N00-N19 and N25-N29).

RESULTS

During 724,063.62 person-years of follow-up, 262 participants died due to kidney disease. The risk of kidney disease-related mortality was higher with increasing duration of biomass use for cooking or house heating (HR for every 10-year increase: 1.20; 95% CI: 1.04-1.37), while it was not associated with increased duration of using kerosene (10-y HR: 1.09; 95% CI: 0.95-1.24) or gas (10-y HR: 1.00; 95% CI: 0.86-1.16). Estimates for lifetime duration of fuel burning for both cooking and house heating (exclusive fuel use) did not differ according to whether used heating stoves were chimney-equipped or not for kerosene, while they differed for biomass (10-y HR, chimney-equipped: 1.06 [95% CI: 0.95-1.18]; 10-y HR, not chimney-equipped: 1.19 [95% CI: 1.06-1.34]; P difference = 0.025).

DISCUSSION: The findings of our study suggest that burning biomass for household purposes under poor ventilating conditions is associated with kidney disease-related mortality.