Chronic Kidney Disease in Nicaragua

Funding Source: World Bank Award
PI: Daniel Brooks, DSc, BUSPH
Co-Investigators: Michael McClean, ScD, BUSPH; Ann Aschengrau, ScD, BUSPH; Kate Applebaum, ScD, BUSPH; Madeleine Scammell, DSc, BUSPH

ebrg_3We are currently conducting an investigation of chronic kidney disease (CKD) in the northwestern region of Nicaragua in conjunction with the World Bank and Nicaraguan partners. CKD is a major international public health concern that is increasing worldwide, and while the most common causes in developed countries are diabetes and hypertension, the etiology of CKD in Nicaragua is unknown. If not properly treated, CKD can lead to end stage renal disease (ESRD) and often death, particularly in developing countries where patients do not typically have access to dialysis and kidney transplants.

Prevalence and mortality studies have demonstrated that the occurrence of CKD is higher in the northwestern region as compared to other areas of Nicaragua. Here, CKD is also higher in men than in women and is elevated among younger age groups as compared to other areas of Nicaragua and the United States. This area of the country is home to the Ingenio San Antonio (ISA), the operational center of the National Sugar Estates Limited (NSEL), the largest of four sugar cane companies in Nicaragua such that thousands of young men in this region are ISA employees. Northwestern Nicaragua is also unique in its geography because it contains several active volcanoes, which may increase the background levels of heavy metals in environmental media. Some of these metals are associated with adverse renal function, but a causal link between exposure to metals and CKD in this area has not been established. Though many other causes have been hypothesized, it is unlikely that any one agent is causing the excess of CKD in northwestern Nicaragua. Rather, several of these factors acting in synergy could be responsible for the epidemic, making the goal of determining the root cause very complex.

Some former ISA workers who have been diagnosed with CKD have formed ASOCHIVIDA (translates to the Chichigalpa Association for Life), a citizens group that has fueled investigations of CKD in this region. The two major objectives (identified by both NSEL and ASOCHIVIDA as key partners) are: (1) to determine the causes of CKD in this region of Nicaragua and (2) to determine if there is any link between the work practices at ISA and the causes of CKD. Our team has conducted a scoping study (to define the problem, develop hypotheses, and propose research activities) as well as an industrial hygiene assessment at ISA and a preliminary investigation of contaminants in drinking water. We continue to plan and conduct additional research activities which include the analysis of metals and agrichemicals in soil and drinking water, an assessment of exposures and kidney function among ISA field workers, and biological sampling. We are also designing a pilot study of ISA workers to provide preliminary data in support of a subsequent larger cohort study. Importantly, there will be ongoing dialogue sessions with NSEL and ASOCHIVIDA to keep them informed and engaged in the process.