Whilst delineating the genetic factors that influence pathologies can be facilitated through laboratory work or small clinical trials, researchers must often employ large population studies to determine environmental triggers for disease. Chronic kidney disease (CKD) is a highly prevalent condition that can lead to manifestations of nerve damage, anaemia, and cardiovascular disease, and is of keen interest to the medical community. Observations of its prevalence among workers in hot climates prompted researchers from the University of Colorado Anschutz Medical Campus, Colorado, USA, to analyse available cohort-based studies of the disease in order to identify potential environmental risk factors.
The team’s research suggested that agricultural workers in the sugarcane, corn, and cotton industries were more likely to develop CKD compared to workers at higher altitudes. They hypothesised that increasingly high temperatures (caused by climate change), as well as exposure to pesticides, such as glyphosphate, could be fuelling the epidemic. This was evident in Sri Lankan workers who are routinely exposed to this compound, as well as kidney-damaging heavy metals, such as lead and cadmium.
CKD is spreading among North American agricultural workers. The life-threatening effects of CKD become even more serious when considering the rising global population and need for sustainable food production. Dr Richard Johnson from the University of Colorado’s School of Medicine and co-author of the study had obvious concerns: “They are the people who feed the planet. […] If climate change continues like this, who is going to feed us?”
The authors acknowledge that other factors, including kidney-targeting infectious diseases, heavy labour, dehydration, and genetic factors, likely feed into the disease’s regulatory network; however, they commented that this presentation of CKD is not the typical because it is not caused by high blood pressure or diabetes. Dr Johnson and his colleagues advocate for an improvement of worker’s conditions, and that “when clinicians detect clusters of patients with [CKD] who work for the same employer or in similar jobs, they should contact occupational health and safety and public health professionals to promote investigations of workplace conditions.”