Now, an interdepartmental team of Boston University School of Public Health [BUSPH] researchers is on the case, sifting for answers.
"The disease has, essentially, been a death sentence once you get it," said BUSPH researcher Daniel Brooks, an associate professor of epidemiology who leads the group. "We don't often have public health epidemics [where] we really have no idea what the cause is. In this case, that is the situation."
Since 2009, Brooks has led a research team from BU to probe why residents of two regions of northwestern Nicaragua -- Chinandega and Leon -- are contracting chronic kidney disease at a rate more than 10 times that in the U.S. Under the auspices of the World Bank's Office of the Compliance Advisor/Ombudsman (CAO), the team has developed a strategy to probe possible reasons for the epidemic and is conducting a wide-ranging study to try to pinpoint causes.
The scientists are working with a few clues that they hope may lead them to answers. Previous studies indicate that deaths are more common among men than women, and that the disease is striking people as young as 20 or 30 years old.
Among those with the disease are a large number of former agricultural workers at a sugar cane plantation owned by the largest employer in the area, Nicaragua Sugar Estates Limited (NSEL). A group of former NSEL employees have alleged that the company was exposing workers to something that was causing the epidemic -- a claim disputed by the company. The workers formed a group, ASOCHIVIDA, which lodged a complaint in 2008 with the CAO (the World Bank's private sector arm, IFC, provided a million loan to the sugarcane operation in 2006).
In response, the CAO brought together workers and sugarcane company management to try to find answers, with the BU interdisciplinary team retained to develop a strategy for studying possible causes.
To date, the BUSPH team has done studies on everything from the work processes used at NSEL, to the agrichemicals used on crops, to screening water samples for contaminants known to cause chronic kidney disease. Nothing, so far, has been shown to explain the excess occurrence of chronic kidney disease.
The research team and other stakeholders spoke of their challenges and progress at a recent forum at Boston University Medical Campus, headlined "An Epidemic of Chronic Kidney Disease in Nicaragua: BUSPH Responds to a Public Health Crisis." Attendees included Juan Jose Amador, a Nicaraguan health professional who is working in the affected community; Amar Inamdar, a CAO representative who is overseeing the conflict between the Nicaraguan sugarcane company and the organization of former workers; and Juan Dumas, an expert in conflict management who is mediating the complex dialogue process that is central to the study of this epidemic.
"Nicaragua Sugar Estates Limited may be conducting itself in accordance with work practices that we say [are] okay," said Inamdar, principal specialist, ombudsman at the World Bank's Office of the Compliance Advisor/Ombudsman. "But does that tell you why or how kidney disease is happening among a good 30 percent of the workforce? No."
"People have been looking for an answer for a number of years and they haven't found one," said Brooks. "There have been various theories, from heat to infectious disease to toxin exposure. It's very much still a mystery."
Besides Brooks, other members of the research team include: Ann Aschengrau, professor of epidemiology; Michael McClean, associate professor of environmental health; Madeleine Scammell, assistant professor of environmental health; Kate Applebaum, assistant professor of epidemiology; Bruce Cohen, adjunct assistant professor of epidemiology and director of research and epidemiology at the Massachusetts Department of Public Health; and James Kaufman, MD, a renal specialist at the BU School of Medicine. Also working with the team is Daniel Weiner, a renal specialist at Tufts University School of Medicine, and Oriana Ramirez, a specialist in preventive medicine studying at Universidad Autónoma de Madrid.
While the main goal of the researchers is to identify causes and end the epidemic, Brooks said that the study process itself has fostered important advances, including a growing trust and collaboration between the various stakeholders involved.
"How do we make them work as a group to fight [chronic kidney disease]?" said Dumas, a conflict management expert. "I believe that is our main challenge. This is about people cooperating."
For now, the researchers plan to continue testing sugar cane workers, interviewing local physicians, and examining other possible occupational and nonoccupational exposures.
For his part, Brooks, whose regular areas of research center on tobacco-related disease and cancer epidemiology, said he is hopeful that the combined skills of epidemiologists, environmental health professionals, renal disease specialists, and global health scholars eventually will lead to answers.
"This may be the most challenging, but also the most meaningful, work I've undertaken," Brooks said. "It's not often that we have a chance to do work that could have such a profound and direct impact on people's lives."
Submitted by Lisa Chedekel and Elana Zak