title: Does Acute Kidney Injury From an Ultramarathon Increase the Risk for Greater Subsequent Injury?
abstract: OBJECTIVE
  Examine whether the acute kidney injury (AKI) commonly observed among ultramarathon participants places the individual at risk for subsequent AKI of worse magnitude.
  
  
  METHODS
  Observational.
  
  
  METHODS
  Western States Endurance Run.
  
  
  METHODS
  Race finishers with postrace blood studies.
  
  
  METHODS
  Acute kidney injury after 1 race.
  
  
  METHODS
  Extent of AKI in subsequent race.
  
  
  RESULTS
  Among 627 finishes in which serum creatinine values were known, 36.2% met "risk" or "injury" criterion with this group characterized by having faster finish times, greater body weight loss during the race, and higher postrace serum creatine kinase and urea nitrogen concentrations when compared with those not meeting the criteria. We identified 38 runners who had undergone postrace blood analyses at multiple races among which 16 (42.1%) met the risk or injury criterion at the first race. Of those 16 runners, 12 (75%) met the criteria at a subsequent race, an incidence that was higher (P = 0.0026) than the overall 36.2% incidence. For most (56.2%) of the 16 runners meeting the criteria at the first race, the subsequent race caused less increase in serum creatinine concentration and decrement in estimated glomerular filtration rate than the first race.
  
  
  CONCLUSIONS
  Mild AKI is common in 161-km ultramarathons, but there was no evidence that previous AKI caused greater renal dysfunction from a subsequent exercise stimulus of similar magnitude. This offers some reassurance to runners and their physicians that mild to moderate AKI in the setting of an ultramarathon is not cumulative or without complete recovery of kidney function when stressed.
authors.affiliation: *Department of Physical Medicine and Rehabilitation, Department of Veterans Affairs, Northern California Health Care System, and University of California Davis Medical Center, Sacramento, CA; and †Department of Medicine, Department of Veterans Affairs, Northern California Health Care System, and Division of Nephrology, Department of Internal Medicine, University of California Davis Medical Center, Sacramento, CA.
authors.forename: Martin D
authors.initials: MD
authors.lastname: Hoffman
authors.forename: Robert H
authors.initials: RH
authors.lastname: Weiss
mesh_terms: D058186:Acute Kidney Injury / Q000097:blood / Q000175:diagnosis / Q000209:etiology*; D000328:Adult; D015415:Biomarkers / Q000097:blood; D003404:Creatinine / Q000097:blood; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D012420:Running / Q000502:physiology*
chemical_list: D015415:Biomarkers; D003404:Creatinine