Chronic Kidney Disease in Central American Workers - Interventions (Part 4 of 4)

Part 1- Introduction

History of the Epidemic in Central America

Statistics

Chronic Kidney Disease – basics

Part 2 – Research and Literature Review

                        Introduction to the Research

                        Etiology

                        Morphology and Pathology

                        Possible Solutions

                        Areas for Additional Research

Part 3 – Social Impacts

                        Narrative

                        Financial Impacts

Part 4 - Interventions

 Sugarcane worker in Nicaragua chopping down sugarcane

http://www.fairfood.org/project/sugarcane-central-america/

Interventions

Setting workplace interventions to alleviate and reduce the intensity of labor and heat exhaustion has been the primary message of several organizations that aim to end Chronic Kidney Disease . The Worker Health Efficiency (WE) Program in El Salvador works with several organizations to provide sugar cane workers with water, rest, shade and more effective tools. Representatives from OSHA provide recommendations for safe working conditions, and Camelbak provides discounted water packs to the WE program.  Allowing workers to properly hydrate and rest in shaded areas has reduced heat stress thus preventing the repeated acute kidney damage that leads to Chronic Kidney Disease. The Australian Cane Farmers Association  teach cane cutters techniques to preserve energy and increase productivity.  The WE program has taken responsible measures to reduce occupational hazards for sugarcane workers.

Sugarcane workers refilling their water packs

Communities across Latin America are pushing for the industry to reconsider paying hourly wages. Many workers are paid by the weight of sugar cane harvested and are under extreme pressure to be as efficient as possible. In the short video "OFF AIR" by the Isla Foundation, sugarcane workers discuss the reality and fear of retribution when speaking out.  In Nicaragua, the Nicaragua Sugar Estates Limited (NSEL) cut off the monthly food stipend of workers who talked about working conditions to the media. The primary source of income for many families is working sugarcane fields. The risk of losing jobs, food stipends and medical provisions will  discourage communities from demanding change.

The cause of Chronic Kidney Disease is widely discussed and consensus has not been reached on causal relationships. In El Salvador, pesticides are the primary concern. In 2013 El Salvadoran congress passed legislation to ban the import of pesticides in an effort to protect  against diseases. Researchers are attempting to collect stronger evidence on the causes of Chronic Kidney Disease to cement the relationship between occupational hazards and CKD. Many believe an extreme ban of pesticides will derail the conversation and impede occupational interventions.  

This series was researched and written by (in alphabetical order by last name): Jessica Chepp, Aleena McDaniel, Cara McShane, Christine Spees, and Kimberly Vargas
All are Master of Public Health candidates at the University of Illinois - Chicago

Chronic Kidney Disease in Central American Workers - Social Impacts (Part 3 of 4)

Photo Credit: Ed Kashi

Part 1- Introduction

History of the Epidemic in Central America

Statistics

Chronic Kidney Disease – basics

Part 2 – Research and Literature Review

                        Introduction to the Research

                        Etiology

                        Morphology and Pathology

                        Possible Solutions

                        Areas for Additional Research

Part 3 – Social Impacts

                        Narrative

                        Financial Impacts

Part 4 - Interventions

Narrative

Barú Ordoñez was 13 years old when he began working on the sugar cane plantations of Ingenio San Antonio, the predominant sugar cane producer in his town of Chichigalpa, Nicaragua. After only two seasons of work as a cañero, he had abnormal levels of creatinine, calcium, and potassium. Upon finding this out, he began to imagine his future unfolding the same way his father’s did; also a cañero, his father died from failed kidneys when Barú was young. Barú never wanted to work as a cañero, but it was his only choice. After becoming ill, he could not go on to study and find better work; at 20 years old, he says, “my dreams have already passed me by.” In Ordoñez’s village, La Isla, almost three quarters of the men have Chronic Kidney Disease; it is so prevalent, and death is so common, that the village has become known as “The Isle of Widows”.

In the same town, Maudiel Martinez says through protruding cheekbones and a pale face, while hunched over like a much older man - he is 19 - “The way this sickness is - you see me now, but in a month I could be gone. It can take you down all of a sudden”. Those dying are young – in their 20’s and 30’s – and are being taken at the prime of their lives. Martinez’ father, grandfather, and three brothers were all affected by CKDu. The disease has devastated communities where men work in the sugar cane fields, leaving grieving loved ones behind as more young men continue to die far too young.

Man receiving dialysis at home. After years of working on sugar cane plantations, he developed CKDu.
http://www.cnn.com/2016/05/02/health/mystery-kidney-disease-global-spread/

Communities

The people of affected communities can only guess at the possible cause for the deadly epidemic. As the BBC reported, “most of the men who are ill show no signs of high blood pressure or diabetes - the most common causes of CKD elsewhere in the world” (“Mystery Kidney Disease in Central America”). Some communities believe that the men are becoming severely dehydrated from long days of work in the hot sun, making them more susceptible to toxins, noting that “it has been seen that a person who works in the sugar cane fields loses approximately 2.4 kg [5.3 lbs] of weight in one working day” Many of the sugar cane workers have pointed to agrochemicals as a potential culprit, though the association between the widely used Roundup chemical and the disease has yet to be proven. As discussed in part 2 of this series, there may be a variety of causes of CKDu, making it difficult to impossible for researchers to find a single cause. This provides few concrete solutions, and little comfort, for the victims and their families. The intervention methods of providing shade and encouraging workers to try to stay hydrated are a start, but it is not clear yet how much of an impact these interventions will be – or how closely they will be followed by the workers.

Financial Impacts

In addition to the emotional toll of the disease on families losing their fathers, brothers, sons, and husbands, the financial toll is also great -  as the disease progresses, the cost of treatment to stay alive far exceeds their income;
dialysis costs tens of thousands of dollars annually, while the laborers might only make a couple thousand dollars a year, if they are fortunate. In Chichigalpa, Ingenio San Antonio (the sugar can plantation where Barú Ordoñez worked) decided to begin testing employees for kidney failure; if they were affected, they were laid off. This has also been true for employees of the Pellas Group, another major sugar can plantation. “The sick workers who have been dismissed say what they receive from the companies and from social security isn't enough to live on — and when they lose their jobs, they lose the right to be treated at company clinics,” making treatment unlikely.

Continue to Part 4 - Interventions

This series was researched and written by (in alphabetical order by last name): Jessica Chepp, Aleena McDaniel, Cara McShane, Christine Spees, and Kimberly Vargas
All are Master of Public Health candidates at the University of Illinois - Chicago

Chronic Kidney Disease in Central American Workers - Research and Review of Literature (part 2 of 4)

Part 1- Introduction

History of the Epidemic in Central America

Statistics

Chronic Kidney Disease – basics

Part 2 – Research and Literature Review

                        Introduction to the Research

                        Etiology

                        Morphology and Pathology

                        Possible Solutions

                        Areas for Additional Research

Part 3 – Social Impacts

                        Narrative

                        Financial Impacts

Part 4 - Interventions

Research Introduction

There have been numerous studies regarding the etiology, diagnosis, and epidemiological trends surrounding Mesoamerican nephropathy (MeN), however, there is much that remains unknown about MeN as a form of chronic kidney disease. With an estimated twenty thousand deaths since 2002, it is crucial that research is conducted to fully understand what causes MeN. Not only is this a major public health concern because this form of kidney disease is associated with significant morbidity and high mortality rates in affected areas, but dialysis and transplants as methods of replacing renal function is not widely offered or available in many areas where Mesoamerican nephropathy is endemic (Correa-Rotter, Wesseling, & Johnson, 2014).

Etiology

In the academic article, “CKD of Unknown Origin in Central America: The Case for a Mesoamerican Nephropathy”, several possible causes for this disease are summarized. Authors include possible chemical or pesticide exposure, infectious diseases including leptospirosis, repeated heat stress and associated dehydration, childhood exposures, and illegal alcohol use. Social determinants of health, including low socioeconomic status, are also addressed as it is believed it may push people to work long hours in very difficult physical conditions to achieve economic stability (Correa-Rotter, Wesseling, & Johnson, 2014).

            Many of these causes were addressed at the First International Research Workshop on Mesoamerican Nephropathy that took place in Costa Rica in 2012 (Wesseling, et al, Program on Work, Environment and Health in Central America, & Central American Institute for Studies on Toxic Substances). Research on MeN has increased and evolved over the last several years. For instance, at the Second International Research Workshop on Mesoamerican Nephropathy, held in 2015, it was emphasized that deleterious health effects of repeated dehydration and heat stress may be more strongly linked to chronic kidney disease of unknown origin than previously thought, while other possible theories, such as heavy metals and pesticide use, have become less widely accepted (Wesseling, et al, Program on Work, Environment and Health in Central America, & Central American Institute for Studies on Toxic Substances, 2015). Additional research has led to an even stronger association between MeN and occupational health, while diseases of similar pathology have been identified in other areas of the world. Due to the wide variety of possible causal factors, it seems unlikely that there is only one true cause of Mesoamerican nephropathy.

Morphology and Pathology

A study published in the American Journal of Kidney Disease, assessed the morphologic findings of Mesoamerican kidney disease. Although a small study of eight men with clinical diagnosis of Mesoamerican nephropathy and a history of agricultural work, all participants had similar findings on kidney biopsies.  Their idney biopsies demonstrated chronic glomerular and tubulointerstitial damage (Wiljkstrom, et al, 2013).  Other tests that aid in diagnosis that have been used in this study, as well as other studies addressing pathology include blood tests that look at estimated glomerular filtration rate and low potassium, as well as urine tests that look for protein in the urine (Wiljkstrom, Leiva, et al, 2013).

Another study that highlights the biological changes that occurs in MeN, was a longitudinal study conducted amongst twenty-nine male sugarcane workers from the Leon and Chinandega areas of Nicaragua; both are areas that are heavily affected by MeN. All participants included in the study did not have preexisting kidney disease or diabetes. (Note: Diabetes is a known factor in many cases of kidney disease.)

Some of the defining characteristics that distinguish more traditional chronic kidney disease from chronic kidney disease of unknown origin, also referred to as MeN
https://laislafoundation.org/wp-content/uploads/2012/08/CKDu.jpg?7a2409

The participants had urine and blood taken before and after their work shift on the first day, sixth day, and after 9 weeks. The blood and urine results were shown to have increases in creatinine and blood urea nitrogen with a decrease in glomerular filtration rate - all of which are associated with renal disease - when compared with a reference group. Furthermore, changes were even noted across the workers’ shifts. The authors suggest repeated heat stress and possible use of non-steroidal anti-inflammatory drugs (NSAIDS), which can strain the kidneys as possible causes of MeN (Wesseling, Aragon, Gonzalez, Weiss, Glaser, Bobadilla, Roncal-Jimenez, Correa-Rotter, Johnson, & Barregard, 2016).

           

Possible Solutions

Given a likely multifactorial cause, there are a variety of suggestions throughout research to prevent development of MeN. For those working in the heat, protection from the sun and rest periods are recommended, as well as adequate hydration. It is also recommended to avoid the use of NSAID medications to prevent additional strain to the kidneys. Controlling pesticide use is also recommended to minimize the plethora of health risks that often accompany its use (Elinder, Wernerson, & Wijkstrom, 2015). Due to the likely involvement of numerous social determinants of health, it is important to also consider public health interventions that may alleviate poverty and health disparities in affected countries.

Areas for Additional Research

Additional research regarding the etiology of Mesoamerican nephropathy is necessary for specific public health prevention and treatment programs to be implemented.  Further detailing and examining the role of social determinants of health may also provide additional insight and can help frame public health interventions (Wesseling, Crowe, Hogstedt, Jakobsson, Lucas, Wegman, Program on Work, Environment and Health in Central America, & Central American Institute for Studies on Toxic Substances, 2012). It is critical that more research be conducted on the morphology of MeN so that a diagnosis can be confirmed by objective means. This will provide researchers and clinicians a clearer understanding of the disease, and will ideally help to decrease the associated morbidity and mortality. As a step in that direction, at the First International Research Workshop on Mesoamerican Nephropathy, it was suggested that more resources be allocated to active surveillance of the disease. More resources will open the door for obtaining more data regarding incidence, mortality, and natural history of the disease, as well as focus efforts on improving active surveillance of the disease (Wesseling, Crowe, Hogstedt, Jakobsson, Lucas, Wegman, Program on Work, Environment and Health in Central America, & Central American Institute for Studies on Toxic Substances, 2012).

Continue to Part 3 - Social Impacts

References

Brooks, D., Ramirez-Rubio, O., & Amador, J. (2012, April). CKD in Central America: A

              Hot Issue. American Journal of Kidney Diseases, 59(4), 481-484.

              http://dx.doi.org/10.1053/j.ajkd.2012.01.005

Correa-Rotter, R., Wesseling, C., & Johnson, R. (2014, March). CKD of Unknown

              Origin in Central America: The Case for a Mesoamerican Nephropathy.

              American Journal of Kidney Diseases, 63(3), 506-520.

              http://dx.doi.proxy.cc.uic.edu/10.1053/j.ajkd.2013.10.062

Elinder, G., Wernerson, A, & Wijkstrom, J. (2015, August 25). Mesoamerican

              Nephropathy (MeN): A “New” Chronic Kidney Disease related to                                           Occupational Heat Exposure with Repeated Deprivation of Salts and Water.

International Journal of Nephrology and Kidney Failure, 1(2).

http://dx.doi.org/10.16966/2380-5498.109

Wesseling, C, Aragon, A., Gonzalez, M., Weiss, I., Glaser, J., Bobadilla, N., Roncal-

              Jimenez, C., Correa-Rotter, R., Johnson, R., Barregard, L. (2016, May). Kidney

              function in sugarcane cutters in Nicaragua- A longitudinal study of workers

              at risk of Mesoamerican nephropathy. Environmental Research 147, 125-132.

              http://dx.doi.org/10.1016/j.envres.2016.02.002

Wesseling, C., Crowe, J., Hogstedt, C., Jakobsson, K., Lucas, R., & Wegman, D. (2012).

              Mesoamerican Nephropathy: Report from the International Research

              Workship on MeN. Retrieved from

        http://www.regionalnephropathy.org/wpcontent/uploads/2013/04/Techni               

              cal-Report-for-Website-Final.pdf

Wesseling, C., Crowe, J., Hogstedt, C., Jakobsson, K., Wegman, D, Program on Work,       

Environment and Health in Central America, & Central American Institute for

Studies on Toxic Substances. (2015). Mesoamerican Nephropathy: Report

from the Second International Research Workshop on MeN. Retrieved from   http://www.regionalnephropathy.org/wp-content/uploads/2016/08/MeN-  2015-Scientific-Report-high-resolution_final.pdf

Wijkstrom, J., Leiva, R., Elinder, C., Leiva, S., Trujillo, Z., Trujillo, L., Soderberg, M.,

              Hultenby, K., & Wernerson, A. (2013, November). Clinical and Pathological

              Characterization of Mesoamerican Nephropathy: A New Kidney Disease in

              Central America. American Journal of Kidney Disease, 62(5), 908-918.

              http://dx.doi.org.proxy/uic.edu/10.1053/j.ajkd.2013.05.019

World Health Organization. (2008). Disease and Injury Country Estimates. Retrieved

              October 24, 2016, from

        http://www.who.int/healthinfo/golbal_burden_disease/estimates_country/

              en/

World Health Organization. (Last Updated 2015, January). El Salvador: WHO

              Statistical Profile. Retrieved from

              http://www.who.int/gho/countries/slv.pdf?ua=1.

World Health Organization. (Last Updated 2015, January). Nicaragua: WHO

Statistical Profile. Retrieved from http://www.who.int/gho/countries/nic.pdf?ua=1

  

This series was researched and written by (in alphabetical order): Jessica Chepp, Aleena McDaniel, Cara McShane, Christine Spees, and Kimberly Vargas
All are Master of Public Health candidates at the University of Illinois - Chicago

Chronic Kidney Disease in Central American Workers - Introduction and Statistics (Part 1 of 4)

Workers in the sugar cane fields of the  San Antonio sugar mill in Chichigalpa, Nicaragua.

Photograph: Estban Felix/AP

https://www.theguardian.com/world/2015/feb/16/-sp-nicaragua-kidney-disease-killing-sugar-cane-workers#img-1

Introduction 
Chronic Kidney Disease of unknown causes has become a fatal epidemic in Mesoamerican countries over the past 15 years. This four-part series of blog posts will investigate the issue in-depth, reviewing current literature and covering the following topics:

Part 1- Introduction and Statistics
                        History of the Epidemic in Central America 
                        Statistics
                        Chronic Kidney Disease – basics
  Mesoamerican Nephropathy 

Part 2 – Research and Literature Review
                        Introduction to the Research
                        Etiology
                        Morphology and Pathology
                        Possible Solutions
                        Areas for Additional Research

Part 3 – Social Impacts
                        Narrative
                        Financial Impacts 

Part 4 - Interventions

History of the Epidemic in Central America

Chronic Kidney Disease (CKD) is not a new disease, however in 2002 a spike in chronic kidney disease of unknown causes (CDKu) was noted in Central American agricultural communities. For the following ten years, the spike persisted and what originally appeared to be endemic grew. It became clear that this endemic was, in fact, an epidemic.

In November 2012, the Central American Program for Work, Environment and Health (SALTRA), Central American Institute for Studies on Toxic Substances (IRET), and the Universidad Nacional Costa Rica (UNA) organized a workshop to officially acknowledge the epidemic of CDKu in Central America, and to implement a plan for immediate prevention. Titled “The International Research Workshop on Mesoamerican Nephropathy (MeN)”, the goals of the conference were to:

1. Identify variables in studying at-risk populations
2. Determine a clinical definition of Mesoamerican nephropathy
3. Address and define the epidemic by using current scientific evidence
4. Investigate and prevent fatalities in the most effected populations through collaboration across research groups

In October of 2013, the members of the Pan American Health Organization (PAHO) recognized the epidemic and approved a resolution which called for “stepped-up efforts to investigate and address the environmental and occupational factors believed to underlie the problem” and to “address the problem and mitigate the health, social and economic impacts of the disease."

During the decade between the spike in 2002 and the recognition of the epidemic in 2013 by PAHO, it was estimated that over 20,000 Central Americans died of the disease.  

The interactive map, below, from the PAHO and World Health Organization (WHO), demonstrates the progression of the epidemic along with the countries most affected. Use the slider on the far right to adjust the year and select a country of interest (on the map) for more information on that country. Data can also be stratified by sex and chronic kidney disease or renal failure. 

http://www.paho.org/hq/index.php?option=com_content&view=article&id=9402

Statistics

• Nicaragua and Honduras are in the top 10 for highest mortality rates from kidney disease, with El Salvador having highest in the world (World Health Organization, 2008)
• In 2012, Kidney disease was the sixth leading cause of death in El Salvador and the third leading cause of death in Nicaragua (World Health Organization, 2015)
• Chronic kidney disease was the second leading cause of death in men of working ages in El Salvador (World Health Organization, 2008)
• Several studies have found that men are affected by MeN at about a 3:1 ratio to women (Brooks, Ramirez-Rubio, & Amador, 2012)

Chronic Kidney Disease – The Basics

To gain a better understanding of the epidemic in Mesoamerica, a base line in understanding of kidney function and chronic kidney disease is to be established.

The primary function of the kidneys is to filter excess waste and fluid from the blood which produces the waste product, urine. The additional functions and nuances of the process are complex, and more information can be found on the National Kidney Foundation's webpage, titled "How Your Kidneys Work." However, it is important to note that the kidneys also produce critical hormones for bodily function, and they regulate salt and potassium levels within the body.

http://wikybrew.com/adopt-good-nutrition-delay-chronic-kidney-disease-progress/

When the kidneys stop performing their regular functions, it is called chronic kidney disease (CKD). This is usually brought on by other chronic disorders, such as diabetes or high blood pressure. When the kidneys stop functioning, waste builds up in the body, which, if left untreated, is fatal. If the disease is caught early enough, medicinal interventions can be made to prevent complete failure. When kidneys have completely failed, the only treatment options to prevent death are dialysis or to perform a kidney transplant.

In the case of the epidemic in Mesoamerica, the kidney disease is of unknown origin so it is difficult to treat or prevent. Additionally, due to the lower socioeconomic status of the at-risk populations, treatment options are not always economically feasible. 

Mesoamerican Nephropathy

The prevalence of this form of kidney disease has led several researchers to question the cause of this disease. Mesoamerican nephropathy is defined in the International Research Workshop Report as “persons with abnormal kidney function […] living in Mesoamerica with no other known causes for CKD.” Since the 2012 workshop which established this clinical definition, subsequent research has shown a strong correlation between workers who cut sugar cane and develop chronic kidney disease. With this correlation established, a cause of CKD from working on the sugar cane plantations had to be determined. It is important to note that these workers are typically young men, who have minimal to no other chronic health conditions, and who are healthy when beginning work on the plantations. However, over the course of working on a plantation, CKD often develops and their health deteriorates.

The structure of sugar plantations is such that the workers are exposed to several health hazards. Additionally, the low socioeconomic status of the workers and the culture of the communities is such that the workers have few other options for employment and have very little power to change the conditions they work in. First, due to the nature of the sugar cane industry and growing season, these workers are seasonal, and paid by the weight of sugar cane that they can cut, not by the amount of time they work. Thus, the workers are pushed, either from internal (personal) motivations or from external motivations, to maximize their yields.  This often means that the workers have little motivation to take breaks during the work day. The lack of breaks means a reduction of time in the shade and fewer opportunities to rehydrate throughout the day. In the high-temperature and high humidity regions of central America, where this is occurring, this kind of labor intensive work without breaks and opportunities to rehydrate is detrimental to health and believed to be a major cause of Mesoamerican nephropathy.  Additionally, if the workers become ill, they not only have medical expenses, but have a financial loss from the days not worked – having negative impacts for them and their families. From a medical perspective, there are some simple preventative measures that can be taken, however, the complexity of the social determinants of health should not be ignored in finding a sustainable solution.


Social Determinants of Health

Using a framework or model for health may help understand the complex disease process of Mesoamerican nephropathy. As MeN has been noted to likely have multiple causes, including social determinants of health, using a comprehensive framework, like the WHO Social Determinants of Health Framework, provides additional context. 

WHO Social Determinants of Health Framework

This model accounts for larger forces, called structural determinants of health inequities, which includes policies, sociocultural values, occupation, gender, class, and race/ethnicity, as well as more proximal indicators of health, called intermediary determinants of health, which includes things like behaviors and living/working conditions. The model doesn’t just address how these social determinants can affect health, but how they can perpetuate devastating health inequities.

              When put in the context of MeN, the involvements of various social determinants of health are magnified. On a structural level, one must consider: work safety policies in place (or lack thereof); how a society views work and how specific occupations are perceived (particularly in the sugar cane industry); and how the population affected is generally young, male sugar cane workers in lowland areas (Correa-Rotter, Wesseling, & Johnson, 2014). On a more proximal level, looking at material circumstances like working conditions can provide more insight on the role of social determinants of MeN. The men who work in sugar cane fields often work long hours under extraordinarily hot conditions, with minimal shade and minimal rest periods, throughout the duration of the season.

As one of the most widely accepted theories is that MeN is at least partly due to repeated heat stress and dehydration, it may be helpful to examine the interaction of MeN and social determinants of health in that context (Wesseling, Crowe, Hogstedt, Jakobsson, Lucas, Wegman, Program on Work, Environment and Health in Central America, & Central American Institute for Studies on Toxic Substances, 2015). Sugar cane workers are often paid by weight of the sugar cane they cut, rather than by time spent at work. This promotes working as hard as possible in often unforgiving conditions. There is little incentive for these workers to take breaks to rest in the shade and rehydrate, as it takes time away from earning money, even though it is detrimental to their health. However, the more time the men spend in these conditions without adequate rest and hydration, the more men seem to be affected by MeN, which then leads to loss of income from work due to disease as well as money lost to medical treatment. Enacting policies to support worker’s health and safety, creating work environments where rest and hydration are encouraged, and providing people with other opportunities for economic stability are all levels where public health interventions can improve the Mesoamerican nephropathy epidemic. 

Continue to Part 2 - Research and Literature Review

This series was researched and written by (in alphabetical order): Jessica Chepp, Aleena McDaniel, Cara McShane, Christine Spees, and Kimberly Vargas
All are Master of Public Health candidates at the University of Illinois -Chicago