Environmental and Occupational Risk Factors Associated with Chronic Kidney Disease of Unknown Etiology in West Javanese Rice Farmers, Indonesia

Chronic kidney disease of unknown etiology (CKDu) in agricultural population is an increasing issue. This study aims to obtain a prevalence estimate of CKDu in male rice farmers in West Java, Indonesia; and analyze the relationship between CKDu and environmental and occupational factors. The study design was cross-sectional. This study included 354 healthy male farmers in two rice agriculture areas in West Java with different altitudes (low altitude and high-altitude location). This research included blood and urine sampling from the farmers for serum creatinine (SCr) level and proteinuria; questionnaire on demographic information, occupational factors and other risk factors for CKDu. We measured ambient temperature and humidity in both study locations for environmental factors. From SCr level and proteinuria, we categorized the farmers into five stages of CKD; then we distinguished CKDu from CKD if the farmers had stage 1-4 of CKD but without diabetes, hypertension and other traditional causes. Data were analyzed with multivariate logistic regression to get prevalence odd ratios of CKDu and its relationship with environmental and occupational factors, adjusted with other risk factors of CKDu. The overall prevalence of CKD was 24.9% and CKDu was 18.6%. For the environmental factors, farm location (high altitude versus low altitude location) was associated with CKDu (Prevalence Odds Ratio (POR): 2.0; 95% CI: 1.2-3.5). For the occupational factors, although not significant, the risk of CKDu increased with the longer use of insecticide and with the more frequent of insecticide use. We suggested that there was a need to conduct future research to investigate more on the association of those environmental and occupational factors with CKDu.