Chronic kidney disease in the absence of hypertension and diabetes is a growing problem among agricultural laborers in tropical and subtropical regions. It is unclear if heat stress and dehydration are risk factors for this form of chronic kidney disease (CKDu). To investigate this relationship, agricultural workers in four villages (n = 261) in North Central Province, Sri Lanka completed the US National Institute for Occupational Safety and Health (NIOSH) health hazard evaluation of heat stress, translated into Sinhalese (July 2017). We constructed a heat stress/dehydration index based on the frequency of 16 symptoms (range 0–32; reliability, 0.84). Workers provided a urine sample for dipstick assessment of urine albumin-creatinine ratio (ACR) and refractometer analysis of urine concentration. Of 261 respondents, 41 participants reported diabetes or chronic kidney disease. They scored higher on the heat stress-dehydration index (10.78 vs. 8.03, p < .01) and were more likely to have ACR > 30 (85.4% vs. 69.4%, p < .05). Among 216 non-pregnant agricultural workers without diabetes or kidney disease (mean age, 46.6; 37% male), villagers in the high-CKDu prevalence area were more likely to show signs of dehydration (for example, greater urine concentration, 1.015 vs. 1.012, p < .05, among males); however, the heat stress-dehydration index overall was not associated with ACR or urine concentration. Because an elevated ACR (proteinuria) is not a reliable marker of early CKDu, additional studies are needed to assess the association between heat stress-dehydration symptoms and risk of CKDu.
The urine total-protein-to-creatinine ratio showed a positive significant correlation with urine albumin to creatinine ratio, which is clinically important to identify early stage of diabetic nephropathy. This can be used in rural areas as it is inexpensive.
Objective. We examined heat stress symptoms and urine markers of chronic kidney disease (CKDu) in Sri Lanka to assess differences between endemic vs. non-endemic regions and by occupation. Sample and Methods. We assessed a total of 475 villagers. In the endemic region, 293 were agricultural workers and 67 were not working primarily in agriculture. In the non-endemic region, 76 were agricultural workers. Of the residents, 218 were assessed for neutrophil gelatinase-associated lipocalin (NGAL), an early predictor of acute kidney injury, along with urine markers of chronic kidney disease. Results. The mean (sd) age of the sample was 45.2 (12.6), with males comprising 52.7%; 7.2% reported kidney disease (n = 34), and 5.7% reported diabetes (n = 27). The heat stress index (mean (sd)) was highest among agricultural workers in the endemic region (8.05 (5.9)), intermediate in non-agricultural workers in the endemic region (4.61 (4.5)), and lowest among agricultural workers in the non-endemic region (3.85 (3.3)); p < 0.0001. Correlations were higher between NGAL and serum microalbumin in the endemic agricultural worker sample than in the other two samples (Spearman’s r = 0.34 vs. 0.15 and 0.20). Conclusions. Both heat stress symptoms and NGAL values were higher among agricultural workers in endemic CKDu regions. Correlations between NGAL and microalbumin suggested a link between acute kidney injury and chronic kidney disease in the more-exposed sample.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.