A new study published in The Lancet Regional Health – Southeast Asia has revealed that 5.31% of agricultural workers in Tamil Nadu suffer from chronic kidney disease (CKD), with nearly half of these cases (2.66%) classified as chronic kidney disease of unknown cause (CKDu).
The large-scale, population-based study is the first of its kind in India to systematically assess CKD and CKDu prevalence among agricultural workers. Conducted across five agroclimatic zones in Tamil Nadu, the research involved 3,350 participants selected through stratified multi-stage cluster sampling. All participants underwent detailed clinical evaluations and laboratory tests in two phases.
During the first phase, 584 individuals were found to have an estimated glomerular filtration rate (eGFR) of ≤60 mL/min per 1.73 m² — a key indicator of kidney function. However, when re-evaluated three months later, only 178 participants remained in this category, suggesting that many cases may involve transient subclinical acute kidney injury (AKI), which could potentially contribute to long-term CKD progression.
The study identified several risk factors significantly associated with CKD, including older age, diabetes, hypertension, anaemia, use of smokeless tobacco, lack of formal education, and prolonged outdoor work hours.
Researchers emphasized that CKDu — not linked to diabetes or hypertension — continues to be a major public health concern, especially in regions with high heat exposure and heavy agricultural activity. They called for further investigation into the effects of subclinical AKI, occupational heat stress, agrochemical exposure, and environmental toxins on kidney health.
The findings underscore the urgent need for targeted health interventions and preventive strategies for agricultural workers in India, who remain at heightened risk due to occupational and environmental conditions.