Electrolyte Beverage Intake to Promote Hydration and Maintain Kidney Function in Guatemalan Sugarcane Workers Laboring in Hot Conditions

The Impact of Physical Exercise on Oxidative and Nitrosative Stress: Balancing the Benefits and Risks

This review comprehensively evaluates the effects of physical exercise on oxidative and nitrosative stress, mainly focusing on the role of antioxidants. Using a narrative synthesis approach, data from empirical studies, reviews, systematic reviews, and meta-analyses published between 2004 and 2024 were collated from databases like PubMed, EBSCO (EDS), and Google Scholar, culminating in the inclusion of 41 studies. The quality of these studies was rigorously assessed to ensure the clarity of objectives, coherence in arguments, comprehensive literature coverage, and depth of critical analysis. Findings revealed that moderate exercise enhances antioxidant defenses through hormesis, while excessive exercise may exacerbate oxidative stress. The review also highlights that while natural dietary antioxidants are beneficial, high-dose supplements could impede the positive adaptations to exercise. In conclusion, the review calls for more focused research on tailored exercise and nutrition plans to further understand these complex interactions and optimize the health outcomes for athletes and the general population.

A Pilot Study Examining the Use of Ultrasound to Measure Intravascular Volume Status in Agricultural Workers in a Field-Based Research Setting

OBJECTIVE

The aim of this pilot study was to explore if internal jugular vein (IJV) ultrasound studies on agricultural workers in a field-based research setting could assess volume status during a hydration intervention.

METHODS

We performed pre- and post-work shift IJV ultrasound images on 30 agricultural workers. The IJV collapsibility index values were <39% (euvolemic) or ≥39% (hypovolemic).

RESULTS

Of the water group, 13% (2/15) had an IJV collapsibility index ≥39%, and this increased to 19% (3/16) by the end of the work shifts. The electrolyte group did not have any workers start the work shift with an IJV collapsibility index ≥39%; however, at the postshift assessment, 15% (2/13) were hypovolemic.

CONCLUSION

Internal jugular vein ultrasounds may have the potential to be a useful tool to determine volume status in field-based research settings. Further investigation is needed to confirm these findings.

Occurrence of Occupational Injuries and Within Day Changes in Wet Bulb Temperature Among Sugarcane Harvesters

OBJECTIVE

Climate change has implications for human health worldwide, with workers in outdoor occupations in low- to middle-income countries shouldering the burden of increasing average temperatures and more frequent extreme heat days. An overlooked aspect of the human health impact is the relationship between heat exposure and increased risk of occupational injury. In this study, we examined the association between occupational injury occurrence and changes in outdoor temperatures through the workday among a cohort of Guatemalan sugarcane harvesters.

METHODS

Occupational injuries recorded for the 2014/2015 to 2017/2018 harvest seasons were collected from a large agribusiness employing male sugarcane harvesters in Southwest Guatemala. Wet Bulb Globe Temperature (WBGT) for the same period was collected from the El Balsamo weather station. We used a logistic mixed effects model to examine the association between injury occurrence and (1) the average WBGT during the hour injury was recorded, (2) the average WBGT during the hour prior to the injury being recorded, and (3) the change in the hourly average WBGT prior to the injury being recorded.

RESULTS

There were 155 injuries recorded during the study period. Injuries were recorded most often between 14:00 and 16:00 (n = 62, 40%) followed by 8:00 and 10:00 (n = 56, 36%). There were significant differences in the average hourly WBGT and the hour in which injuries were recorded (p-value <.001). There were no observable associations between average hourly WBGT (OR: 1.00, 95%CI: 0.94, 1.05; p-value: 0.87), lagged average hourly WBGT (OR: 1.01, 95%CI: 0.97, 1.05; p-value: 0.71), or change in average hourly WBGT (OR: 0.96, 95%CI: 0.89, 1.04; p-value: 0.35) and recorded occupational injury.

CONCLUSIONS

This is the first study that has examined how changes in WBGT throughout the day are related to occupational injury among agricultural workers. Although this study did not demonstrate an association, there is a need for future research to examine how various measurements of WBGT exposure are related to occupational injury in agricultural worker populations.

Impact of hydration with beverages containing free sugars or xylitol on metabolic and acute kidney injury markers after physical exercise

The proper fluid and carbohydrates intake is essential before and during physical exercise, and for this reason most athletes drink beverages containing a high amount of free sugars. Sweetened soft drinks are also commonly consumed by those not doing any sport, and this habit seems to be both unhealthy and also the cause of metabolic problems. Recently, several sweeteners have been proposed to replace sugars in popular beverages. To examine the impact of free sugars and the popular sweetener xylitol on metabolic profile and the markers of kidney function and injury after exercise the present study was conducted with semi-professional football players. All participants were healthy, with a mean age of 21.91 years. Their sports skills were on the level of the 4th-5th division of the league. The subjects took part in four football training sessions. During each session they drank a 7% solution of sugar (sucrose, fructose, glucose) or xylitol. The tolerability of these beverages and well-being during exercise was monitored. Before and after each training session, blood and urine were collected. The markers of kidney function and injury, uric acid, electrolytes, complete blood count, CRP, serum albumin, serum glucose and the lipid profile were analyzed. The main finding of this study was that the xylitol beverage is the least tolerated during exercise and 38.89% of participants experienced diarrhea after training and xylitol intake. Xylitol also led to unfavorable metabolic changes and a large increase in uric acid and creatinine levels. A mean increase of 1.8 mg/dl in the uric acid level was observed after xylitol intake. Increases in acute kidney injury markers were observed after all experiments, but changes in urine albumin and cystatin C were highest after xylitol. The other three beverages (containing “free sugars” - glucose, fructose and sucrose) had a similar impact on the variables studied, although the glucose solution seems to have some advantages over other beverages. The conclusion is that sweeteners are not a good alternative to sugars, especially during exercise. Pure water without sweeteners should be drunk by those who need to limit their calorie consumption.

Clinical Trial Registration:ClinicalTrials.gov, (NCT04310514)

The impact of heat on kidney health: A PRISMA-compliant bibliometric analysis

BACKGROUND

Exposure to excessive heat can impact kidney health. Climate change is projected to aggravate this impact. An analysis of articles published between 1958 and 2021 was conducted to explore the progress of the research on this issue.

METHODS

This study included a bibliometric analysis wherein Web of Science was used to generate a list of all published articles related to the impact of heat on kidney health. Basic information about the articles, such as titles, authors' names, keywords, and citations, were recorded and analyzed.

RESULTS

A total of 226 published articles related to the impact of heat on kidney health were identified as of November 20, 2021. Most of these articles (93%) were published within the last decade. The United States was the most prominent country in terms of research productivity and collaboration. Researchers from the United States were well represented among the top 20 contributors of published articles on the study issue. The productivity of the top 20 authors varied between 6 and 32 articles each. A total of 25 common words used by the authors were identified. The most frequently used keywords were chronic kidney disease, heat stress, acute kidney injury, Mesoamerican nephropathy, and climate change. Keyword analysis revealed 3 distinct major research clusters in the existing scientific research on the impact of heat on kidney health: chronic kidney disease of unknown etiology, heat stress and renal physiology, and the effect of climate change on kidney health.

CONCLUSIONS

Research on heat-related kidney injury has witnessed rapid development in recent decades, motivated by the emergence of chronic kidney disease of unknown etiology and climate change. Developing countries in hot regions must increase their productivity in this research area through international collaboration and partnerships.

Workers and Climate Change: The Need for Academic–Industry Partnerships to Improve Agricultural Worker Health, Safety, and Wellbeing

Climate change will have negative consequences for human health worldwide. Agricultural workers are especially vulnerable to the health consequences of climate change. This communication demonstrates how a Total Worker Health® approach is utilized to protect Guatemalan agricultural workers from the negative health effects of climate change. DrPH researchers work alongside local partners to develop, implement, and evaluate climate adaptation strategies and other interventions to improve agricultural worker health, safety, and wellbeing. Training in public health ethics, communications, and leadership gives DrPH researchers the tools to help create successful academic–industry partnerships that increase local capacity and have sustainable public health impact.

Hydration Interventions Among Agricultural Workers: A Pilot Study

OBJECTIVE

To estimate the impact of hydration interventions on postworkday hydration status and incidence of acute kidney injury (AKI).

METHODS

Thirty agricultural workers were first monitored on a workday without any interventions. On the intervention workday, the same workers were randomized to one of two groups: 169 ounces (oz) (5 L) of plain water (n = 16) or 169 oz (5L) of water with electrolytes (n = 14).

RESULTS

No participants in the electrolyte group had an estimate glomerular filtration rate (eGFR) at the end of the workday of less than 90 mL/min/1.73 m2 or met the criteria for AKI in comparison to the water group (eGFR < 90: 15%; AKI: 23%) or the control group (eGFR < 90: 28%; AKI: 18%).

CONCLUSION

The study showed that drinking water with electrolytes may lower the risk for development of AKI among agricultural workers.

Body Composition, Anemia, and Kidney Function among Guatemalan Sugarcane Workers

Rates of anemia among agricultural workers, who are also at risk for kidney injury and chronic kidney disease of unknown cause (CKDu), are unknown. We evaluated body composition through the sum of three skinfolds among 203 male sugarcane cutters and assessed the relationship of variables related to nutrition, anemia (hemoglobin < 13 g/dL), and elevated hemoglobin A1c (HbA1c ≥ 5.7%) with estimated glomerular filtration rate (eGFR) using linear regression. Eleven percent of workers were at the level of essential body fat (2-5%). Anemia was present among 13% of workers, 70% of which were normochromic normocytic, a type of anemia suggesting potential underlying chronic disease. Anemia was more common among those with lower BMI and fat free mass. The prevalence of elevated HbA1c was 21%. A moderate negative correlation was found between hemoglobin and HbA1c (Pearson's r = -0.32, p <0.01) which suggests that HbA1c values should be interpreted with caution in populations that have high rates of anemia. Twelve percent of workers had reduced kidney function with an eGFR < 90 mL/min/1.73 m². On average, the eGFR was 18 mL/min per 1.73 m² lower [(95% CI:-24, -12), p <0.01)] for those with anemia than those without, and 8 mL/min per 1.73 m² lower among those with elevated HbA1c [(95% CI: -13, -2), p < 0.01]. Results will inform future studies examining the role of anemia in the evaluation of CKDu and interventions to improve nutrition for workers in low-resource settings.

International Total Worker Health: Applicability to Agribusiness in Latin America

Total Worker Health^® (TWH) is a framework for integrating worker and workplace safety, health, and well-being, which has achieved success in European and US settings. However, the framework has not been implemented in Latin America or in agricultural sectors, leaving large and vulnerable populations underrepresented in the implementation and evaluation of these strategies to improve safety and promote health and well-being. This study presents a case study of how a TWH approach can be applied to a multinational Latin American agribusiness. We describe the process and adaptation strategy for conducting a TWH assessment at multiple organizational levels and in multiple countries. We follow this with a description of a TWH leadership training that was conducted based on the results of the assessment. Finally, we describe our methods to make corporate recommendations for TWH policies and programs that were informed by the TWH assessment and leadership trainings. With this case study we aim to demonstrate the importance and feasibility of conducting TWH in Latin America.

Wet Bulb Globe Temperature and Recorded Occupational Injury Rates among Sugarcane Harvesters in Southwest Guatemala

As global temperatures continue to rise it is imperative to understand the adverse effects this will pose to workers laboring outdoors. The purpose of this study was to investigate the relationship between increases in wet bulb globe temperature (WBGT) and risk of occupational injury or dehydration among agricultural workers. We used data collected by an agribusiness in Southwest Guatemala over the course of four harvest seasons and Poisson generalized linear modelling for this analysis. Our analyses suggest a 3% increase in recorded injury risk with each degree increase in daily average WBGT above 30 °C (95% CI: -6%, 14%). Additionally, these data suggest that the relationship between WBGT and injury risk is non-linear with an additional 4% acceleration in risk for every degree increase in WBGT above 30 °C (95% CI: 0%, 8%). No relationship was found between daily average WBGT and risk of dehydration. Our results indicate that agricultural workers are at an increased risk of occupational injury in humid and hot environments and that businesses need to plan and adapt to increasing global temperatures by implementing and evaluating effective occupational safety and health programs to protect the health, safety, and well-being of their workers.