Exercise-associated Hyponatremia Research Articles

Exercise-Associated Hyponatremia in the Grand Canyon: Preventing Fatalities through Early Recognition, Timely Therapy, and Education.

Exercise-Associated Hyponatremia in the Grand Canyon: Preventing Fatalities through Early Recognition, Timely Therapy, and Education.

Assessment and initial management of the collapsed endurance athlete

Participation in endurance events such as marathons is increasingly popular. Those taking part in these events may collapse and require medical attention for a range of reasons, some of which are well known and recognised by prehospital providers. However, there are conditions that are specific to endurance exercise which may be less well known so potentially less likely to be recognised and managed appropriately. The most common cause of collapse in the endurance athlete is exercise-associated collapse. However, practitioners should be vigilant regarding life-threatening differentials such as exertional heatstroke and exercise-associated hyponatraemia, which are not uncommon. Identifying the cause of collapse in the endurance athlete is difficult as clinical presentations are often similar. The causes, symptoms and management of these conditions are discussed and a management algorithm proposed.

Clinical presentation of exercise-associated hyponatremia in male and female IRONMAN® triathletes over three decades.

Exercise-associated hyponatremia (EAH) is common in ultra-endurance events and severe cases are more common in females. The purpose of this paper is to compare the clinical presentation of EAH between male and female triathletes in ultra-endurance competitions. Medical records with sodium concentrations (n = 3138) from the IRONMAN® World Championships over the timeframe of 1989-2019 were reviewed for both male (n = 2253) and female (n = 885) competitors. Logistic regression was used to explore the relationships between sex, sodium concentration, and various clinical presentations. When comparing male and female triathletes, clinical variables found to have a different relationship with sodium concentration include altered mental status (inversely related in males and not related in females), abdominal pain, muscle cramps, hypotension, and tachycardia (directly related in males and not related in females), and vomiting and hypokalemia (not related in males and inversely related in females). Overall, males lost significantly more weight than females, and notably, approximately half of all athletes were dehydrated and lost weight. Altered mental status, vomiting, abdominal pain, muscle cramps, hypotension, tachycardia, and hyperkalemia appear to present differently between sexes when comparing hyponatremic to eunatremic athletes. Although overhydration is the most common etiology of hypervolemic hyponatremia, hypovolemic hyponatremia comprises a significant amount of hyponatremic triathletes. Further understanding of how EAH presents helps athletes and medical professionals identify it early and prevent life-threatening complications.

Fructose: A New Variable to Consider in SIADH and the Hyponatremia Associated With Long-Distance Running?

Fructose has recently been proposed to stimulate vasopressin secretion in humans. Fructose-induced vasopressin secretion is not only postulated to result from ingestion of fructose-containing drinks but may also occur from endogenous fructose production via activation ofthe polyol pathway. This raises the question of whether fructose might be involved in some cases of vasopressin-induced hyponatremia, especially in situations where the cause is not fullyknown such as in the syndrome of inappropriate secretion of diuretic hormone (SIADH) and exercise-associated hyponatremia, which has been observed in marathon runners. Here we discuss the new science of fructose and vasopressin, and how it may play a role in some of theseconditions, as well as in the complications associated with rapid treatment (such as the osmotic demyelination syndrome). Studies to test the role of fructose could provide new pathophysiologic insights as well as novel potential treatment strategies for these common conditions.

Ultra-Endurance Participation and Acute Kidney Injury: A Narrative Review

Increasingly popular, ultra-endurance participation exposes athletes to extremely high levels of functional and structural damage. Ultra-endurance athletes commonly develop acute kidney injury (AKI) and other pathologies harmful to kidney health. There is strong evidence that non-steroidal anti-inflammatory drugs, common amongst ultra-athletes, is linked to increased risk and severity of AKI and potentially ischaemic renal injury, i.e., acute tubular necrosis. Ultra-endurance participation also increases the risk of exertional rhabdomyolysis, exercise-associated hyponatremia, and gastrointestinal symptoms, interlinked pathologies all with potential to increase the risk of AKI. Hydration and fuelling both also play a role with the development of multiple pathologies and ultimately AKI, highlighting the need for individualised nutritional and hydration plans to promote athlete health. Faster athletes, supplementing nitrates, and being female also increase the risk of developing AKI in this setting. Serum creatinine criteria do not provide the best indicator for AKI for ultra-athletes therefore further investigations are needed to assess the practicality and accuracy of new renal biomarkers such as neutrophil gelatinase-associated lipocalin (NGAL). The potential of recurring episodes of AKI provide need for further research to assess the longitudinal renal health impact of ultra-participation to provide appropriate advice to athletes, coaches, medical staff, and event organisers.

Exercise-Associated Hyponatremia in Marathon Runners.

Exercise-associated hyponatremia (EAH) was first described as water intoxication by Noakes et al. in 1985 and has become an important topic linked to several pathological conditions. However, despite progressive research, neurological disorders and even deaths due to hyponatremic encephalopathy continue to occur. Therefore, and due to the growing popularity of exercise-associated hyponatremia, this topic is of great importance for marathon runners and all professionals involved in runners' training (e.g., coaches, medical staff, nutritionists, and trainers). The present narrative review sought to evaluate the prevalence of EAH among marathon runners and to identify associated etiological and risk factors. Furthermore, the aim was to derive preventive and therapeutic action plans for marathon runners based on current evidence. The search was conducted on PubMed, Scopus and Google Scholar using a predefined search algorithm by aggregating multiple terms (marathon run; exercise; sport; EAH; electrolyte disorder; fluid balance; dehydration; sodium concentration; hyponatremia). By this criterion, 135 articles were considered for the present study. Our results revealed that a complex interaction of different factors could cause EAH, which can be differentiated into event-related (high temperatures) and person-related (female sex) risk factors. There is variation in the reported prevalence of EAH, and two major studies indicated an incidence ranging from 7 to 15% for symptomatic and asymptomatic EAH. Athletes and coaches must be aware of EAH and its related problems and take appropriate measures for both training and competition. Coaches need to educate their athletes about the early symptoms of EAH to intervene at the earliest possible stage. In addition, individual hydration strategies need to be developed for the daily training routine, ideally in regard to sweat rate and salt losses via sweat. Future studies need to investigate the correlation between the risk factors of EAH and specific subgroups of marathon runners.

Acute Kidney Injury and Hyponatremia in Ultra-Trail Racing: A Systematic Review.

Background and objectives: Ultra-trail races can cause episodes of acute kidney injury (AKI) and exercise-associated hyponatremia (EAH) in healthy subjects without previous renal pathology. This systematic review aims to review the incidence of these two syndromes together and separately taking into account the length and elevation of the ultra-trail race examined. Materials and Methods: A systematic review was conducted through electronic search in four electronic databases (PubMed, EBSCO, Web of Science and Alcorze). Results: A total of 1127 articles published between January 2006 and December 31, 2021 were included, 28 of which met the inclusion criteria. The studies were categorized according to the length and stages of the race in four categories: medium (42 to 69 km), long (70 to 99 km), extra (>100 km) and multi-stage if they included various stages. A total of 2950 runners (666 females and 2284 males) were extracted from 28 publications. The AKI incidence found was 42.04% (468 cases of 1113), and 195 of 2065 were diagnosed with EAH, accounting for 9.11%. The concurrence of both pathologies together reached 11.84% (27 individuals) from a total of 228 runners with AKI and EAH simultaneously analyzed. Sorted by race category, the AKI+EAH cases were distributed as follows: 18 of 27 in the extra (13.63% and n = 132), 4 in the large (5.79% and n = 69) and 5 in the medium category (18.15% and n = 27). Conclusions: According to these results, extra and medium races showed a similar incidence of AKI+EAH. These findings underline the importance of the duration and intensity of the race and may make them responsible for the etiology of these medical conditions. Due to their variable incidence, EAH and AKI are often underdiagnosed, leading to poorer prognosis, increased condition seriousness and hindered treatment. The results of this review urge participants, coaches and race organizers to take measures to improve the early diagnosis and urgent treatment of possible EAH and AKI cases.

A review of risk factors and prevention strategies for exercise associated hyponatremia.

Exercise-associated hyponatremia (EAH) is defined as a serum sodium concentration under 135mmol·L-1 during or within 24h of exercise. Increasing interest in endurance events has led to a higher number of athletes presenting with this potentially life-threatening condition. EAH is largely caused by the overconsumption of hypotonic fluids leading to weight gain during exercise. The primary risk factors include the inappropriate secretion of arginine vasopressin, longer exercise duration, smaller body mass, and to smaller extent ingestion of non-steroidal anti-inflammatory drugs. Accurate tracking of fluid intake and losses to prevent weight gain during exercise, sodium supplementation, and heat acclimatization may help attenuate declines in serum sodium concentration during exercise.

Exercise-Induced Hyponatremia: An Assessment of the International Hydration Recommendations Followed During the Gran Trail De Peñalara and Vitoria-Gasteiz Ironman Competitions.

IntroductionHyponatremia often occurs during the practice of endurance sports. We evaluated the impact on hyponatremia of the hydration recommendations of the Third International Exercise-Associated Hyponatremia Consensus Development Conference 2015 (3IE-AHCD) during the 2017 Gran Trail de Peñalara marathon (GTP) and the Vitoria Gasteiz Ironman triathlon (VGI).MethodsProspective study of GTP and VGI athletes participating in four information sessions in the months prior to the events, to explain that hydration should only be according to their level of thirst, per the recommendations of the 3IE-AHCD. Consenting event finishers were included in final analysis. Pre- and post-race anthropometric and biochemical parameters were compared.ResultsThirty-six GTP (33 male) and 94 VGI (88 male) finishers were evaluated. GTP race median fluid intake was 800 ml/h, with 900 ml/h in the VGI race. 83.3% GTPfin and 77.6% VGIfin remained eunatremic (blood sodium 135–145 mmol/L). Only 1/36 GTP and 1/94 VGI participant finished in hyponatremia, both with a sodium level of 134 mmol/L. Fourteen percent of GTP, and 21.2% of VGI participants finished in hypernatremia, with no increase in race completion times. No participating athlete required medical attention, except for musculoskeletal complaints. Pro-BNP and Copeptin levels rose significantly. Changes in copeptin levels did not correlate with changes in plasma osmolality, nor total body water content in impedance analysis.ConclusionsRecommending that athletes' fluid intake in endurance events be a function of their thirst almost entirely prevented development of hyponatremia, without induction of clinically significant hypernatremia, or a negative repercussion on race completion times.

Medical emergencies during running events

HintergrundDie Anzahl an kurz- und langstreckigen Laufveranstaltungen in Deutschland nimmt zu. Laufen als Breitensport wird von einer Vielzahl an Personen unterschiedlicher Altersklassen, Risikogruppen und Professionalisierungsgrade betrieben, woraus ein breites Spektrum medizinischer Notfälle resultiert.Ziel der ArbeitDer vorliegende Beitrag erläutert die Inzidenz, Pathophysiologie und Therapie relevanter Notfallbilder bei Laufveranstaltungen. Ziel ist die Optimierung der Arbeitsabläufe des Rettungsdienstpersonals.Material und MethodenEs erfolgte eine Literaturrecherche in PubMed.ErgebnisseAnstrengungsassoziierte Muskelkrämpfe, gastrointestinale Symptome, Kollaps, Kompartmentsyndrom und Tendinopathien sind häufige Erscheinungsbilder und resultieren meist aus akuter oder chronischer Überanstrengung. Der Kreislaufstillstand bzw. plötzliche Herztod ist ein seltenes Ereignis bei Laufveranstaltungen. Bewusstseinsstörungen und generalisierte Krampfanfälle sind schwerwiegende Komplikationen. Disseminierte intravasale Koagulopathie, belastungsinduzierte Hyponatriämie, Hitzschlag, Rhabdomyolyse und thromboembolische Ereignisse sind mit hoher Morbidität und Mortalität verbunden. Substanzen zur Erhöhung der Schmerzschwelle und leistungssteigernde Substanzen sind unter Läufern stark verbreitet und gehen mit einer hohen Rate an Nebenwirkungen einher.DiskussionUnspezifische Symptome wie Erbrechen, Fieber, Kollaps, Muskelschmerzen, Übelkeit, und Schwäche sind die führenden Symptome bei Laufveranstaltungen. Eine sorgfältige Anamnese ist wegweisend für eine zielgerichtete klinische Therapie. Präklinisch steht eine Symptomkontrolle im Mittelpunkt. Das Flüssigkeitsmanagement stellt eine besondere Herausforderung dar.

Changes in Factors Regulating Serum Sodium Homeostasis During Two Ultra-Endurance Mountain Races of Different Distances: 69km vs. 121km.

Overdrinking and non-osmotic arginine vasopressin release are the main risk factors for exercise-associated hyponatremia (EAH) in ultra-marathon events. However, particularly during ultra-marathon running in mountainous regions, eccentric exercise and hypoxia, which have been shown to modulate inflammation, hormones regulating fluid homeostasis (hypoxia), and oxidative stress, could contribute to serum sodium changes in a dose-dependent manner. To the best of our knowledge, the contribution of these factors, the extent of which depends on the duration and geographical location of the race, has not been well studied. Twelve male participants (11 finishers) of the short (69km, 4,260m elevation-gain) and 15 male participants (seven finishers) of the long (121km, 7,554m elevation-gain) single-stage Südtirol Ultra Sky-Race took part in this observational field study. Venous blood was drawn immediately before and after the race. Analyses included serum sodium concentration, copeptin (a stable marker for vasopressin), markers of inflammation, muscle damage and oxidative stress. Heart rate was measured during the race and race time was obtained from the race office. During the short and the long competition two and one finishers, respectively showed serum sodium concentrations >145mmol/L. During the long competition, one athlete showed serum sodium concentrations <135mmol/L. Only during the short competition percent changes in serum sodium concentrations of the finishers were related to percent changes in body mass (r=−0.812, p=0.002), total time (r=−0.608, p=0.047) and training impulse (TRIMP) (r=−0.653, p=0.030). Data show a curvilinear (quadratic) relationship between percent changes in serum sodium concentration and body mass with race time when including all runners (short, long, finishers and non-finishers). The observed prevalence of hypo- and hypernatremia is comparable to literature reports, as is the relationship between serum sodium changes and race time, race intensity and body mass changes of the finishers of the short race. The curvilinear relationship indicates that there might be a turning point of changes in serum sodium and body mass changes after a race time of approximately 20h. Since the turning point is represented mainly by non-finishers, regardless of race duration slight decrease in body mass and a slight increase in serum sodium concentration should be targeted to complete the race. Drinking to the dictate of thirst seems an adequate approach to achieve this goal.

Marathon Runners' Knowledge and Strategies for Hydration.

To study hydration plans and understanding of exercise-associated hyponatremia (EAH) among current marathon runners. Cross-sectional study. Southern California 2018 summer marathon. Two hundred ten marathon runners. Survey administered 1 to 2 days before the race. Race times were obtained from public race website. Planned frequency of hydration; awareness of, understanding of, and preventative strategies for dehydration and EAH; resources used to create hydration plans; drink preferences. When the participants were split into 3 equal groups by racing speed, the slower tertile intended to drink at every mile/station (60%), whereas the faster tertile preferred to drink every other mile or less often (60%), although not statistically significant. Most runners (84%) claimed awareness of EAH, but only 32% could list a symptom of the condition. Both experienced marathoners and the faster tertile significantly had greater understanding of hyponatremia compared with first-time marathoners and the slower tertile, respectively. Less than 5% of marathoners offered "drink to thirst" as a prevention strategy for dehydration or EAH. Slower runners plan to drink larger volumes compared with their faster counterparts. Both slower and first-time marathoners significantly lacked understanding of EAH. These groups have plans and knowledge that may put them at higher risk for developing EAH. Most marathon runners did not know of the guidelines to "drink to thirst," suggesting the 2015 EAH Consensus statement may not have had the desired impact.

Two-Screen Virtual Board Game Didactic for Teaching Wilderness and Environmental Medicine Topics to Emergency Medicine Residents.

This game is appropriate for medical students, interns, junior and senior residents. The COVID-19 pandemic has forced a transition from in-person to virtual learning, and educators must innovate and adapt to keep learners engaged. One way to achieve this is through gamification.1 The authors employed a novel approach to gamification of virtual learning which engaged not only learners' computers but also their mobile phones. Learners worked in teams communicating by text message to answer ABEM board-style questions and occupy sites on the virtual board. By the end of this didactic, the learner will:1. Describe the basics of the presentation of each topic listed above2. Recall the basics of management of each topic listed above3. Improve learners' preparedness for the Emergency Medicine Inservice Exam and Written Board Examination. Wilderness and environmental medicine topics were selected from the list of topics covered on the ABEM boards. Questions were then written by the authors teaching these concepts. Learners were surveyed immediately following the session using an evaluation tool containing both Likert-scale questions on quality and applicability as well as open-ended questions on strengths and areas for improvement. The response rate to this survey was 100%. Feedback was overwhelmingly positive, with 19/20 respondents rating the sessions 5/5 for effectiveness and value of teaching compared with other sessions, and 1/20 rating the session 4/5. Nineteen out of twenty respondents rated the content as "highly relevant"; 1/20 rated it as "mostly relevant." Nineteen out of twenty respondents rated the session 5/5 for being engaging and holding their attention; 1/20 rated it as somewhat engaging. Learners rated the session as highly relevant and engaging. We hypothesize that by engaging two screens and forcing learners to work together by text message, we were able to turn what would normally be a distraction (texting co-residents during resident conference) into a tool for learning. Electrical injury, lightning strike, thermal burns, inhalational injury, chemical burns, acute radiation syndrome, snake bites, scorpion envenomation, stingray envenomation, jellyfish stings, black widow spider bites, mammalian bites, rabies, murine typhus, bear encounters, decompression sickness, arterial gas embolism, drowning, dehydration, heat stroke, exercise-associated hyponatremia, frostbite, hypothermia, CO poisoning, hydrogen sulfide poisoning, giardia.

Incidence of exercise-associated hyponatremia during a high-altitude 161-km ultramarathon.

[Purpose]Exercise-associated hyponatremia (EAH) is a well-known condition among endurance athletes at low altitudes. The incidence of EAH during ultramarathons at high altitudes warrants further investigation. This prospective observational study was conducted on the participants of the Leadville Trail 100 run, a 161-km race held at a high altitude (2,800 m-3,840 m).[Methods]Venous blood samples were collected before and immediately after the race. The participants completed an electronic survey after the race. Our main outcome measure was the post-race serum sodium ([Na+]) level.[Results]Of the 672 athletes who started the race, 351 (52%) successfully completed the event within the 30-hour cut-off. Post-race blood samples were collected from 84 runners (66 finishers). Both pre- and post-race blood samples were collected from 37 participants. Twenty percent of the post-race participants had EAH. Only one post-race participant had a [Na+] level of <130 mmol/L. All participants with EAH were asymptomatic. One participant had an abnormal pre-race [Na+] level (134 mmol/L). Female participants had a significantly higher rate of EAH than male participants (40% vs. 16%; p=0.039). Age, body mass index, weight changes, race completion status, nonsteroidal anti-inflammatory drug use, and urine specific gravity were not associated with the development of EAH. Lower postrace [Na+] levels were associated with higher serum creatine kinase values (R2=0.1, p<0.005).[Conclusion]High altitude (3,840 m peak) does not appear to enhance the incidence of EAH after an ultramarathon footrace. This suggests that ambient temperature (low temperatures reduce risk), sex (female predilection), endurance running, and overhydration are more prominent risk factors for EAH than high altitude.

Comparison Of Hydration Practices Of Long-distance Runners During Covid-19: A Cross-sectional Study

PURPOSE: To assess and compare the self-reported hydration practices of long-distance runners during an intended long training run and an intended event during COVID-19. Inconsistent hydration practices may lead to overhydration, a primary cause of exercise-associated hyponatremia (EAH). METHODS: Cross-sectional survey design. An online survey utilized both the North Dakota State University online community and a Connecticut running group listserv(s) in October, 2020. A long-distance runner was defined as one who had completed at least one ten-mile run. Survey questions addressed hydration practices, including hydration strategies and volumes consumed before and during an intended long-distance training run (LTR) and an intended race. Demographics, training experience, sources of hydration information, and knowledge of EAH were collected. RESULTS: The comparison of self-reported hydration strategies between an intended LTR and an intended event showed moderate agreement (0.74) among n = 203. The agreement between an intended LTR and an intended event was statistically significant when estimated by the Kappa statistics (K = 0.674; p < 0.0001). When comparing intended volumes during a LTR and an event, there was a correlation of 0.74. In a one-sided paired t-test, the intended volumes during an event were significantly greater than the intended volumes during a LTR (t = 5.99; p < 0.0001). Runners reported “drinking according to thirst” 24% of the time during an intended LTR, compared to 23% of the time for their intended event. Finally, this study found that 59% reported knowledge and awareness of EAH, while 89% felt they had a solid understanding an effective hydration plan for long distance running. CONCLUSIONS: In this study, long-distance runners reported some differences in planned hydration practices when comparing an intended long training run to an intended event. Drinking according to thirst is recommended to prevent EAH in lieu of a personalized hydration plan. If runners mimic appropriate hydration practices, such as drinking according to thirst, during training when running an event, the risk of EAH may be decreased. This indicates a need for ongoing education on hydration practices and EAH. The primary limitation of this study was the self-reported nature of historical data.

Clinical Presentation Of Exercise-associated Hyponatremia In Male And Female Ironman-distance Triathletes Over Three Decades

Clinical Presentation Of Exercise-associated Hyponatremia In Male And Female Ironman-distance Triathletes Over Three Decades

Hydration Practices of Long-Distance Trail Runners Competing in Connecticut (CT) During COVID-19

ObjectivesThe purpose of this research is to assess and compare the self-reported hydration practices of long-distance trail runners during an intended long training run (LTR), an intended event, and during an actual event during COVID-19. The hypothesis is that hydration practices are inconsistent between these three scenarios and runners sometimes consume more than intended during an event. Consuming more fluids than intended may lead to exercise-associated hyponatremia (EAH).MethodsCross-sectional pre- and post-survey design. The setting was the Macedonia Trail Race was in Kent, CT and the Angevine Farm Trail Race was in Warren, CT. A total of 26 (of 310 registered) eligible runners from one of the events volunteered to be participants. The pre-race survey assessed intended hydration practices of training and a possible event. The post-race assessed the actual hydration practices of the race. Main outcome measures were hydration practices, including strategies and volumes during a LTR, and intended event, and the actualevent. Awareness and knowledge of EAH, and the understanding of an effective hydration plan were assessed.ResultsThere was a strong correlation (0.91) between intended volumes before the LTR and the intended event. When comparing volumes consumed during the event to the intended event, the correlation was moderate (0.52). Moderate agreement (64–85%) was found when comparing the hydration strategies in the intended and the actual events. The comparisons were statistically significant when measured by the Kappa statistic (P < 0.05). Runners reported drinking according to thirst an average of 30% across the three scenarios. This study found that 50% of runners reported knowledge and awareness of EAH, while 62% felt they had a solid understanding of an effective hydration plan.ConclusionsIn this study, long-distance trail runners reported differences in hydration practices when comparing an intended LTR, an intended trail event, and an actual trail event. Drinking according to thirst is the recommended hydration strategy to prevent EAH, in lieu of a personalized hydration plan. This indicates a need for ongoing education on hydration practices and EAH. The primary limitations of this study are self-reported data and small sample size due to COVID-19.Funding SourcesNone

Thermal strain and fluid balance during a 72-km military route march in a field setting.

A physiological profiling study was conducted to evaluate thermal strain as well as fluid and electrolyte balances on heat-acclimatised men performing a 72-km route march in a field setting. 38 male soldiers (age range 18-23 years) participated in the study, as part of a cohort that marched for 72 km, with loads for about 26 hours. Core temperature and heart rate sensors were used for the duration of the march. Fluid and food intake and output were monitored for the duration of the march. Blood samples were taken one day before the march (pre-march), immediately after the march (Post 1) and on the 15th day after the march to ascertain recovery (Post 2) to assess fluid and electrolyte profiles. Mean core temperature was within safe limits, ranging from 37.1 to 38.1°C throughout the march. There was an overall decrease in serum sodium levels, a decline in serum sodium concentration in 28 participants and three instances of hyponatraemia (serum sodium concentration <135 mmol/L). Our study found low thermal strain heat-acclimatised individuals during a 72-km route march. However, there was an overall decrease in serum sodium levels, even when the participants were allowed to drink ad libitum. Challenges of exercise-associated hyponatraemia during prolonged activities remain to be addressed.

Prehospital management of exertional heat stroke at sports competitions: International Olympic Committee Adverse Weather Impact Expert Working Group for the Olympic Games Tokyo 2020

ObjectivesThis document aimed to summarise the key components of exertional heat stroke (EHS) prehospital management.MethodsMembers of the International Olympic Committee Adverse Weather Impact Expert Working Group for the Olympic Games...

The management of hyperthermia and exercise-associated hyponatremia in low-resource and prehospital settings

Between 2000 and 2016, the number of people exposed to heat waves worldwide increased by around 125 million. As global warming increases, there is growing concern regarding the effect of heat stress on health outcomes, particularly in low- and middle-income tropical countries. The likelihood of developing heat-related injury depends on three factors: an individual, their environment, and their workload. Both exertional hyperthermia and exercise-induced hyponatremia are potentially life-threatening conditions that may develop in environments with increased heat stress. These can present with vague and overlapping symptoms such as confusion, headache, vomiting, and in severe cases, coma. The management of these two conditions is extremely different, and making a correct diagnosis can be challenging, particularly for health-care professionals who are working in low-resource or prehospital settings.