Consensus Statement of the 1st International Exercise-Associated Hyponatremia Consensus Development Conference, Cape Town, South Africa 2005

Over the past decade, exercise-associated hyponatremia (EAH) has emerged as an important complication of prolonged endurance activity. Prior to 1985, this condition was not reported, and runners generally finished marathons with weight loss but without serious medical complications. Abnormalities of serum sodium concentrations ([Na]), when measured, were confined to elevated levels consistent with varying degrees of volume depletion. In March 2005, a panel of twelve international experts on exercise physiology, sport medicine, water metabolism and body fluid homeostasis convened in Cape Town, South Africa, for the 1st International Exercise-Associated Hyponatremia Consensus Development Conference. The primary goal of this panel was to review all of the existing data on EAH and formulate an evidence-based analysis that would define the current understanding of the pathophysiology of EAH. In particular, the panel was constituted to facilitate integration of existing medical and scientific knowledge of other forms of hyponatremia with the occurrence of this homeostatic imbalance during endurance exercise. A secondary goal of the EAH Consensus Development Conference was to prepare a statement that would serve to curtail the growing problem of EAH by disseminating the most current information to both medical personnel and the greater public on the prevalence, nature and treatment of this disorder. The panel strived to clearly articulate what we agreed upon, debate issues that we did not agree upon, and describe in detail what we did and did not know, including minority viewpoints that were supported by clinical and experimental data. The following statement reflects a concise summary of the data deliberated and synthesized by the panel and provides a ‘‘snapshot in time’’ of the current state of knowledge on EAH. New knowledge will continue to advance regarding our understanding of EAH, and will mandate future updates to this consensus statement.

[1]  T. Noakes,et al.  Hyponatraemic encephalopathy despite a modest rate of fluid intake during a 109 km cycle race , 2005, British Journal of Sports Medicine.

[2]  D. Wypij,et al.  Hyponatremia among runners in the Boston Marathon. , 2005, The New England journal of medicine.

[3]  J. Verbalis,et al.  Sodium status of collapsed marathon runners. , 2005, Archives of pathology & laboratory medicine.

[4]  T. Noakes Sodium ingestion and the prevention of hyponatraemia during exercise , 2004, British Journal of Sports Medicine.

[5]  T. Noakes,et al.  Weight changes, medical complications, and performance during an Ironman triathlon , 2004, British Journal of Sports Medicine.

[6]  T. Noakes,et al.  Study of Hematological and Biochemical Parameters in Runners Completing a Standard Marathon , 2004, Clinical journal of sport medicine : official journal of the Canadian Academy of Sport Medicine.

[7]  T. Noakes,et al.  The dipsomania of great distance: water intoxication in an Ironman triathlete , 2004, British Journal of Sports Medicine.

[8]  D. Stoddard Fluid replacement during marathon running. , 2004, Clinical journal of sport medicine : official journal of the Canadian Academy of Sport Medicine.

[9]  S. Horvath,et al.  Acute blood biochemical alterations in response to marathon running , 1975, European Journal of Applied Physiology and Occupational Physiology.

[10]  R. Maughan,et al.  Dehydration and serum biochemical changes in marathon runners , 2004, European Journal of Applied Physiology and Occupational Physiology.

[11]  J. Verbalis,et al.  Disorders of body water homeostasis. , 2003, Best practice & research. Clinical endocrinology & metabolism.

[12]  B. Knechtle,et al.  Effects of different sodium concentrations in replacement fluids during prolonged exercise in women , 2003, British journal of sports medicine.

[13]  B. Glace HYPONATREMIA AND RHABDOMYOLYSIS - RUNNER , 2003 .

[14]  M. Sawka,et al.  Effectiveness of revised fluid replacement guidelines for military training in hot weather. , 2003, Aviation, space, and environmental medicine.

[15]  J. Chorley,et al.  The Incidence, Risk Factors, and Clinical Manifestations of Hyponatremia in Marathon Runners , 2003, Clinical journal of sport medicine : official journal of the Canadian Academy of Sport Medicine.

[16]  J. Thompson,et al.  Hyponatremic Encephalopathy in A Marathon Runner , 2003 .

[17]  A. Kratz,et al.  Effect of marathon running on hematologic and biochemical laboratory parameters, including cardiac markers. , 2002, American journal of clinical pathology.

[18]  J. Thompson,et al.  Oral Salt Supplementation During Ultradistance Exercise , 2002, Clinical journal of sport medicine : official journal of the Canadian Academy of Sport Medicine.

[19]  K. Stuempfle,et al.  Hyponatremia in a cold weather ultraendurance race. , 2002, Alaska medicine.

[20]  J. Gardner,et al.  Fatal water intoxication of an Army trainee during urine drug testing. , 2002, Military medicine.

[21]  Tsang-Hai Huang,et al.  THE EFFECTS OF DIFFERENT ENDURANCE SWIMMING INTENSITIES ON BONE DEVELOPMENT IN RATS , 2002 .

[22]  C. Callaway,et al.  Hyponatremia in runners requiring on-site medical treatment at a single marathon. , 2002, Medicine and science in sports and exercise.

[23]  J. Gardner Death by water intoxication. , 2002, Military medicine.

[24]  T. Noakes,et al.  Peak rates of diuresis in healthy humans during oral fluid overload. , 2001, South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde.

[25]  T. Noakes,et al.  Response to a fluid load in athletes with a history of exercise induced hyponatremia. , 2001, Medicine and science in sports and exercise.

[26]  D. Davis,et al.  Exercise-associated hyponatremia in marathon runners: a two-year experience. , 2001, The Journal of emergency medicine.

[27]  M. Sawka,et al.  Hyponatremia associated with overhydration in U.S. Army trainees. , 2001, Military medicine.

[28]  T. Noakes,et al.  Fluid Balance During and After an Ironman Triathlon , 2001, Clinical journal of sport medicine : official journal of the Canadian Academy of Sport Medicine.

[29]  T. Noakes,et al.  Exercise-Induced Hyponatremia in Ultradistance Triathletes Is Caused By Inappropriate Fluid Retention , 2000, Clinical journal of sport medicine : official journal of the Canadian Academy of Sport Medicine.

[30]  S. Flinn,et al.  Seizure After Exercise in the Heat , 2000, The Physician and sportsmedicine.

[31]  T. Berl Mannitol: a therapeutic alternative in the treatment of acute hyponatremia? , 2000, Critical care medicine.

[32]  J. Varon,et al.  Hyponatremia, Cerebral Edema, and Noncardiogenic Pulmonary Edema in Marathon Runners , 2000, Annals of Internal Medicine.

[33]  T. Noakes,et al.  A Prospective Study of Exercise-Associated Hyponatremia in Two Ultradistance Triathletes , 2000, Clinical journal of sport medicine : official journal of the Canadian Academy of Sport Medicine.

[34]  T. Noakes,et al.  Diagnosis and Prevention of Hyponatremia at an Ultradistance Triathlon , 2000, Clinical journal of sport medicine : official journal of the Canadian Academy of Sport Medicine.

[35]  I. Rogers,et al.  Hyponatremia and seizures in an ultradistance triathlete. , 2000, The Journal of emergency medicine.

[36]  H. Barkan,et al.  Exertional heat illness and hyponatremia in hikers. , 1999, The American journal of emergency medicine.

[37]  M. Sawka,et al.  Fluid replacement recommendations for training in hot weather. , 1999, Military medicine.

[38]  A. Arieff,et al.  Chronic hyponatremic encephalopathy in postmenopausal women: association of therapies with morbidity and mortality. , 1999, JAMA.

[39]  T. Noakes,et al.  Hyponatremia in ultradistance triathletes. , 1999, Medicine and science in sports and exercise.

[40]  O. Bar-or,et al.  Preventing dehydration in children with cystic fibrosis who exercise in the heat. , 1999, Medicine and science in sports and exercise.

[41]  D. Vrijens,et al.  Sodium-free fluid ingestion decreases plasma sodium during exercise in the heat. , 1999, Journal of applied physiology.

[42]  T P Garigan,et al.  Death from hyponatremia as a result of acute water intoxication in an Army basic trainee. , 1999, Military medicine.

[43]  N. C. Reynolds,et al.  Complications of fluid overload in heat casualty prevention during field training. , 1998, Military medicine.

[44]  C. Stone,et al.  Iatrogenic acute hyponatraemia in a college athlete. , 1998, British journal of sports medicine.

[45]  M. Hamlin,et al.  Hyponatremia and Weight Changes in an Ultradistance Triathlon , 1997, Clinical journal of sport medicine : official journal of the Canadian Academy of Sport Medicine.

[46]  J. Hellemans,et al.  Weight Changes and Serum Sodium Concentrations After an Ultradistance Multisport Triathlon , 1997, Clinical journal of sport medicine : official journal of the Canadian Academy of Sport Medicine.

[47]  C. Putterman,et al.  Case series: hyponatremia associated with moderate exercise. , 1996, The American journal of the medical sciences.

[48]  P. Douglas,et al.  Fluid and Electrolyte Status in Athletes Receiving Medical Care at an Ultradistance Triathlon , 1995, Clinical journal of sport medicine : official journal of the Canadian Academy of Sport Medicine.

[49]  G. Dhatt,et al.  Lesson of the Week: Cystic fibrosis presenting as hyponatraemic heat exhaustion , 1995, BMJ.

[50]  A. Arieff,et al.  Clinical Investigations in Critical CarePulmonary Complications of Hyponatremic Encephalopathy: Noncardiogenic Pulmonary Edema and Hypercapnic Respiratory Failure , 1995 .

[51]  A. Wolfson Acute hyponatremia in ultra-endurance athletes. , 1995, The American journal of emergency medicine.

[52]  J. M. Clark,et al.  Encephalopathy due to severe hyponatremia in an ultramarathon runner. , 1993, The Western journal of medicine.

[53]  R. Hubbard,et al.  Symptomatic hyponatremia during prolonged exercise in heat. , 1993, Medicine and science in sports and exercise.

[54]  A. Arieff,et al.  Postoperative Hyponatremic Encephalopathy in Menstruant Women , 1992, Annals of Internal Medicine.

[55]  M N Sawka,et al.  Physiological consequences of hypohydration: exercise performance and thermoregulation. , 1992, Medicine and science in sports and exercise.

[56]  O. Bar-or,et al.  Voluntary dehydration and heat intolerance in cystic fibrosis , 1992, The Lancet.

[57]  D. Costill,et al.  Fluid replacement during prolonged exercise: effects of water, saline, or no fluid. , 1991, Medicine and science in sports and exercise.

[58]  T. Noakes,et al.  Evaluation of renal function and fluid homeostasis during recovery from exercise-induced hyponatremia. , 1991, Journal of applied physiology.

[59]  Y. Epstein,et al.  Hyponatremia induced by exercise: a 24-hour endurance march study. , 1991, Mineral and electrolyte metabolism.

[60]  D. Peterson,et al.  Long-term neurologic outcome in psychogenic water drinkers with severe symptomatic hyponatremia: the effect of rapid correction. , 1990, The American journal of medicine.

[61]  Hiller Wd Dehydration and hyponatremia during triathlons. , 1989 .

[62]  W. Hiller Dehydration and hyponatremia during triathlons. , 1989, Medicine and science in sports and exercise.

[63]  W. Kapoor,et al.  Hyponatremia in a Marathoner. , 1988, The Physician and sportsmedicine.

[64]  S. Landaas,et al.  Biochemical changes and endocrine responses in cystic fibrosis in relation to a marathon race. , 1988, International journal of sports medicine.

[65]  A. Arieff,et al.  Treatment of symptomatic hyponatremia and its relation to brain damage. A prospective study. , 1987, The New England journal of medicine.

[66]  F. Sciurba,et al.  Delirium and pulmonary edema after completing a marathon. , 1987, The American review of respiratory disease.

[67]  M. O'Toole,et al.  Medical and physiological considerations in triathlons , 1987, The American journal of sports medicine.

[68]  R. Frizzell,et al.  Hyponatremia and ultramarathon running. , 1986, JAMA.

[69]  T D Noakes,et al.  Water Intoxication: A Possible Complication During Endurance Exercise , 2005, Medicine and science in sports and exercise.

[70]  C. Wade Response, regulation, and actions of vasopressin during exercise: a review. , 1984, Medicine and science in sports and exercise.

[71]  R. Stern,et al.  Exercise and Heat Stress in Cystic Fibrosis Patients , 1983, Pediatric Research.

[72]  T. Noakes,et al.  Metabolic responses to a 90 km running race. , 1982, South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde.

[73]  J. Frommer,et al.  Rapid correction of severe hyponatremia with intravenous hypertonic saline solution. , 1982, The American journal of medicine.

[74]  R. Shephard,et al.  Fluid and Mineral Needs of Middle-Aged and Postcoronary Distance Runners. , 1978, The Physician and sportsmedicine.

[75]  I. Cohen,et al.  Changes in serum electrolyte levels during marathon running. , 1978, South African medical journal = Suid-Afrikaanse tydskrif vir geneeskunde.

[76]  R. Shephard,et al.  On the choice of fluid for the hydration of middle-aged marathon runners. , 1977, British journal of sports medicine.

[77]  R. Jamison,et al.  The urinary concentrating mechanism. , 1976, The New England journal of medicine.

[78]  S. Massry,et al.  NEUROLOGICAL MANIFESTATIONS AND MORBIDITY OF HYPONATREMIA: CORRELATION WITH BRAIN WATER AND ELECTROLYTES , 1976, Medicine.

[79]  T. Kavanagh,et al.  Marathon running after myocardial infarction. , 1974, JAMA.

[80]  C. Kleeman,et al.  Diuretic-induced hyponatremia. , 1971, Annals of internal medicine.

[81]  L. Rose,et al.  Serum electrolyte changes after marathon running. , 1970, Journal of applied physiology.

[82]  W. Schwartz,et al.  A syndrome of renal sodium loss and hyponatremia probably resulting from inappropriate secretion of antidiuretic hormone. , 1957, The American journal of medicine.