1
|
Khodaee M, Saeedi A, Harris-Spinks C, Hew-Butler T. Incidence of exercise-associated hyponatremia during a high-altitude 161-km ultramarathon. Phys Act Nutr 2021; 25:16-22. [PMID: 34727684 PMCID: PMC8580585 DOI: 10.20463/pan.2021.0016] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2021] [Accepted: 09/06/2021] [Indexed: 11/22/2022] Open
Abstract
[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.
Collapse
Affiliation(s)
- Morteza Khodaee
- University of Colorado School of Medicine, Department of Family Medicine and Orthopedics, Denver, USA
| | - Anahita Saeedi
- University of Massachusetts, Department of Biostatistics, MA, USA
| | | | | |
Collapse
|
2
|
Costello JT, Bhogal AS, Williams TB, Bekoe R, Sabir A, Tipton MJ, Corbett J, Mani AR. Effects of Normobaric Hypoxia on Oxygen Saturation Variability. High Alt Med Biol 2020; 21:76-83. [PMID: 32069121 DOI: 10.1089/ham.2019.0092] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Background: The study is the first to evaluate the effects of graded normobaric hypoxia on SpO2 variability in healthy individuals. Materials and Methods: Twelve healthy males (mean [standard deviation] age 22 [4] years) were exposed to four simulated environments (fraction of inspired oxygen [FIO2]: 0.12, 0.145, 0.17, and 0.21) for 45 minutes, in a balanced crossover design. Results: Sample entropy, a tool that quantifies the irregularity of pulse oximetry fluctuations, was used as a measure of SpO2 variability. SpO2 entropy increased as the FIO2 decreased, and there was a strong significant negative correlation between mean SpO2 and its entropy during hypoxic exposure (r = -0.841 to -0.896, p < 0.001). In addition, SpO2 sample entropy, but not mean SpO2, was correlated (r = 0.630-0.760, p < 0.05) with dyspnea in FIO2 0.17, 0.145, and 0.12 and importantly, SpO2 sample entropy at FIO2 0.17 was correlated with dyspnea at FIO2 0.145 (r = 0.811, p < 0.01). Conclusions: These findings suggest that SpO2 variability analysis may have the potential to be used in a clinical setting as a noninvasive measure to identify the negative sequelae of hypoxemia.
Collapse
Affiliation(s)
- Joseph T Costello
- Extreme Environments Laboratory, School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, United Kingdom
| | - Amar S Bhogal
- Network Physiology Laboratory, UCL Division of Medicine, University College London, London, United Kingdom
| | - Thomas B Williams
- Extreme Environments Laboratory, School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, United Kingdom
| | - Richard Bekoe
- Network Physiology Laboratory, UCL Division of Medicine, University College London, London, United Kingdom
| | - Amin Sabir
- Network Physiology Laboratory, UCL Division of Medicine, University College London, London, United Kingdom
| | - Michael J Tipton
- Extreme Environments Laboratory, School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, United Kingdom
| | - Jo Corbett
- Extreme Environments Laboratory, School of Sport, Health and Exercise Science, University of Portsmouth, Portsmouth, United Kingdom
| | - Ali R Mani
- Network Physiology Laboratory, UCL Division of Medicine, University College London, London, United Kingdom
| |
Collapse
|
3
|
Stacey MJ, Woods DR, Brett SJ, Britland SE, Fallowfield JL, Allsopp AJ, Delves SK. Heat acclimatization blunts copeptin responses to hypertonicity from dehydrating exercise in humans. Physiol Rep 2018; 6:e13851. [PMID: 30221840 PMCID: PMC6139708 DOI: 10.14814/phy2.13851] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Revised: 08/04/2018] [Accepted: 08/10/2018] [Indexed: 11/24/2022] Open
Abstract
Acclimatization favors greater extracellular tonicity from lower sweat sodium, yet hyperosmolality may impair thermoregulation during heat stress. Enhanced secretion or action of vasopressin could mitigate this through increased free water retention. Aims were to determine responses of the vasopressin surrogate copeptin to dehydrating exercise and investigate its relationships with tonicity during short and long-term acclimatization. Twenty-three participants completed a structured exercise programme following arrival from a temperate to a hot climate. A Heat Tolerance Test (HTT) was conducted on Day-2, 6, 9 and 23, consisting of 60-min block-stepping at 50% VO2 peak, with no fluid intake. Resting sweat [Na+ ] was measured by iontophoresis. Changes in body mass (sweat loss), core temperature, heart rate, osmolality (serum and urine) and copeptin and aldosterone (plasma) were measured with each Test. From Day 2 to Day 23, sweat [Na+ ] decreased significantly (adjusted P < 0.05) and core temperature and heart rate fell. Over the same interval, HTT-associated excursions were increased for serum osmolality (5 [-1, 9] vs. 9 [5, 12] mosm·kg-1 ), did not differ for copeptin (9.6 [6.0, 15.0] vs. 7.9 [4.3, 14.7] pmol·L-1 ) and were reduced for aldosterone (602 [415, 946] vs. 347 [263, 537] pmol·L-1 ). Urine osmolality was unchanging and related consistently to copeptin at end-exercise, whereas the association between copeptin and serum osmolality was right-shifted (P = 0.0109) with acclimatization. Unchanging urine:serum osmolality argued against increased renal action of vasopressin. In conclusion, where exercise in the heat is performed without fluid replacement, heat acclimatization does not appear to enhance AVP-mediated free water retention in humans.
Collapse
Affiliation(s)
- Michael J. Stacey
- Department of Surgery and CancerImperial College LondonLondonUnited Kingdom
- Department of Military MedicineRoyal Centre for Defence MedicineBirminghamUnited Kingdom
| | - David R. Woods
- Department of Surgery and CancerImperial College LondonLondonUnited Kingdom
- Carnegie Research InstituteLeeds Beckett UniversityLeedsUnited Kingdom
| | - Stephen J. Brett
- Department of Surgery and CancerImperial College LondonLondonUnited Kingdom
| | | | | | | | - Simon K. Delves
- Institute of Naval MedicineAlverstokeHampshireUnited Kingdom
| |
Collapse
|
4
|
HILL NEILE, DEIGHTON KEVIN, MATU JAMIE, MISRA SHIVANI, OLIVER NICKS, NEWMAN CARRIE, MELLOR ADRIAN, O’HARA JOHN, WOODS DAVID. Continuous Glucose Monitoring at High Altitude—Effects on Glucose Homeostasis. Med Sci Sports Exerc 2018; 50:1679-1686. [DOI: 10.1249/mss.0000000000001624] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
|
5
|
Effect of Chronic Kidney Disease on Changes in Vasopressin System Expression in the Kidney Cortex in Rats with Nephrectomy. BIOMED RESEARCH INTERNATIONAL 2018; 2018:2607928. [PMID: 30013980 PMCID: PMC6022316 DOI: 10.1155/2018/2607928] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/01/2018] [Revised: 04/18/2018] [Accepted: 05/21/2018] [Indexed: 02/01/2023]
Abstract
It is believed that the vasopressinergic system plays an important role in the pathogenesis of chronic kidney disease (CKD). The aim of this study was to evaluate the effect of CKD on changes in vasopressin system expression in the kidney cortex in rats with nephrectomy. The study was performed on 4 groups of Sprague Dawley (SPRD) rats: a control group (CN), 1/2 nephrectomy (N1/2), 2/3 nephrectomy (N2/3), and 5/6 nephrectomy (N5/6). Blood and the kidney cortex were collected to evaluate plasma copeptin concentrations and mRNA expressions of V1a vasopressin receptors (V1aR) and V2 vasopressin receptors (V2R) and V1aR, V2R, and aquaporin 2 (AQP2) protein levels. V1aR and V2R mRNA expression in the kidney cortex was significantly lower in the CN group compared with the other groups. In contrast, the V1aR, V2R, and AQP2 protein levels were significantly higher in the CN group compared with all of the nephrectomized groups. Plasma copeptin concentration was significantly lower in the CN group than in the nephrectomized groups. CKD caused significant changes in the expression of the vasopressinergic system. Further research is needed to explain the mechanisms of the impact of the vasopressinergic system on the kidney in CKD.
Collapse
|
6
|
Stacey MJ, Delves SK, Britland SE, Allsopp AJ, Brett SJ, Fallowfield JL, Woods DR. Copeptin reflects physiological strain during thermal stress. Eur J Appl Physiol 2018; 118:75-84. [PMID: 29075863 PMCID: PMC5754412 DOI: 10.1007/s00421-017-3740-8] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2017] [Accepted: 10/08/2017] [Indexed: 11/22/2022]
Abstract
PURPOSE To prevent heat-related illnesses, guidelines recommend limiting core body temperature (T c) ≤ 38 °C during thermal stress. Copeptin, a surrogate for arginine vasopressin secretion, could provide useful information about fluid balance, thermal strain and health risks. It was hypothesised that plasma copeptin would rise with dehydration from occupational heat stress, concurrent with sympathoadrenal activation and reduced glomerular filtration, and that these changes would reflect T c responses. METHODS Volunteers (n = 15) were recruited from a British Army unit deployed to East Africa. During a simulated combat assault (3.5 h, final ambient temperature 27 °C), T c was recorded by radiotelemetry to differentiate volunteers with maximum T c > 38 °C versus ≤ 38 °C. Blood was sampled beforehand and afterwards, for measurement of copeptin, cortisol, free normetanephrine, osmolality and creatinine. RESULTS There was a significant (P < 0.05) rise in copeptin from pre- to post-assault (10.0 ± 6.3 vs. 16.7 ± 9.6 pmol L-1, P < 0.001). Although osmolality did not increase, copeptin correlated strongly with osmolality after the exposure (r = 0.70, P = 0.004). In volunteers with maximum T c > 38 °C (n = 8) vs ≤ 38 °C (n = 7) there were significantly greater elevations in copeptin (10.4 vs. 2.4 pmol L-1) and creatinine (10 vs. 2 μmol L-1), but no differences in cortisol, free normetanephrine or osmolality. CONCLUSIONS Changes in copeptin reflected T c response more closely than sympathoadrenal markers or osmolality. Dynamic relationships with tonicity and kidney function may help to explain this finding. As a surrogate for integrated physiological strain during work in a field environment, copeptin assay could inform future measures to prevent heat-related illnesses.
Collapse
Affiliation(s)
- Michael John Stacey
- Department of Surgery and Cancer, Imperial College London, Care of General Intensive Care Unit, Hammersmith Hospital Campus, Du Cane Road, London, W12 0HS, UK.
- Department of Military Medicine, Royal Centre for Defence Medicine, ICT Building, Birmingham Research Park, Vincent Drive, Edgbaston, Birmingham, B15 2SQ, UK.
| | - Simon K Delves
- Institute of Naval Medicine, Alverstoke, Hampshire, PO12 2DL, UK
| | | | - Adrian J Allsopp
- Institute of Naval Medicine, Alverstoke, Hampshire, PO12 2DL, UK
| | - Stephen J Brett
- Department of Surgery and Cancer, Imperial College London, Care of General Intensive Care Unit, Hammersmith Hospital Campus, Du Cane Road, London, W12 0HS, UK
| | | | - David R Woods
- Department of Military Medicine, Royal Centre for Defence Medicine, ICT Building, Birmingham Research Park, Vincent Drive, Edgbaston, Birmingham, B15 2SQ, UK
- Carnegie Research Institute, Leeds Beckett University, Leeds, LS6 3QS, UK
| |
Collapse
|
7
|
Baumert M, Surmiak P, Więcek A, Walencka Z. Serum NGAL and copeptin levels as predictors of acute kidney injury in asphyxiated neonates. Clin Exp Nephrol 2016; 21:658-664. [PMID: 27590891 PMCID: PMC5517581 DOI: 10.1007/s10157-016-1320-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Accepted: 08/04/2016] [Indexed: 11/28/2022]
Abstract
Background Acute kidney injury (AKI) is the most common complication of perinatal asphyxia. Recent research indicates that serum neutrophil gelatinase-associated lipocalin (NGAL) is an early marker for AKI, but there are the lacks of data about its use in term neonates with perinatal asphyxia. Methods A prospective cohort study was conducted on 43 term neonates. Umbilical cord blood and 24 h after birth serum NGAL, copeptin, creatinine, and molality were measured in all asphyxiated and controls neonates. Results During the study period, 8 of asphyxiated nenates (18.6 %) suffered from AKI, while 35 newborns have no signs of AKI and 30 healthy infants. We did not observe any differences in creatinine and copeptin levels, as well as serum osmolality in all three investigated groups (AKI, no-AKI, and controls) in cord blood, and 24 h after birth. Serum NGAL levels in umbilical cord blood were significantly higher in the AKI group (174.3 ng/mL) compared with no-AKI (88.5 ng/mL, p = 0.01) and control groups (28.5 ng/mL, p < 0.001), and 24 h after birth (respectively, AKI 152.5 ng/mL vs no-AKI 74.9 ng/mL, p = 0.02 vs controls 39.1 ng/mL, p < 0.001). NGAL concentration showed a strong negative correlation to umbilical artery pH (Rho = −0.42, p = 0.04), base excess (Rho = −0.31, p = 0.03), and Apgar score in 1st min (Rho = −0.41, p = 0.02) and 5th min of life (Rho = −0.20, p = 0.001). ROC curve analysis demonstrated a good predictive value for NGAL levels (>140.7 ng/mL) which allows to diagnose AKI in asphyxiated patients with 88.9 % sensitivity (95 % CI 75–95 %) and 95.0 % specificity (95 % CI 76–99 %). Conclusion NGAL seems to be a promising marker, even in subclinical AKI in neonates, due to its high specificity, but copeptin did not meet expectations.
Collapse
Affiliation(s)
- Małgorzata Baumert
- Department of Neonatology, School of Medicine in Katowice, Medical University of Silesia, Medyków 14 Street, 40-752, Katowice, Poland
| | - Piotr Surmiak
- Department of Neonatology, School of Medicine in Katowice, Medical University of Silesia, Medyków 14 Street, 40-752, Katowice, Poland.
| | - Andrzej Więcek
- Department of Nephrology, Endocrinology and Metabolic Diseases, School of Medicine in Katowice, Medical University of Silesia, Francuska 20/24 Street, 40-027, Katowice, Poland
| | - Zofia Walencka
- Department of Neonatology, School of Medicine in Katowice, Medical University of Silesia, Medyków 14 Street, 40-752, Katowice, Poland
| |
Collapse
|
8
|
Boos CJ, Woods DR, Varias A, Biscocho S, Heseltine P, Mellor AJ. High Altitude and Acute Mountain Sickness and Changes in Circulating Endothelin-1, Interleukin-6, and Interleukin-17a. High Alt Med Biol 2015; 17:25-31. [PMID: 26680502 DOI: 10.1089/ham.2015.0098] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
INTRODUCTION Hypoxia induces an inflammatory response, which is enhanced by exercise. High altitude (HA) leads to endothelial activation and may be proinflammatory. The relationship between endothelial activation, inflammation, and acute mountain sickness (AMS) and its severity has never been examined. METHODS Forty-eight trekkers were studied during a progressive trek at 3833, 4450, and 5129 m at rest postascent (exercise), and then again at rest 24 hours later. Twenty of the subjects were also tested at rest pre- and postexercise at sea level (SL) at 6 weeks preascent. We examined plasma levels of the interleukin 6 (IL-6), 17a (IL-17a), and endothelin-1 (ET-1) along with oxygen saturation (SpO2) and Lake Louise scores (LLS). RESULTS ET-1 (5.7 ± 2.1 vs. 4.3 ± 1.9 pg/mL; p < 0.001), IL-6 (3.3 ± 3.3 vs. 2.4 ± 2.3 pg/mL; p = 0.007), and IL-17a (1.3 ± 3.0 vs. 0.46 ± 0.4 pg/mL; p < 0.001) were all overall significantly higher at HA versus SL. There was a paired increase in ET-1 and IL-6 with exercise versus rest at SL, 3833, 4450, and 5129 m (p < 0.05). There was a negative correlation between LLS and SpO2 (r = -0.32; 95% confidence interval [CI] -0.21 to -0.42; p < 0.001) and a positive correlation between LLS and IL-6 (r = 0.16; 0.0-0.27; p = 0.007) and ET-1 levels (r = 0.29; 0.18-0.39; p < 0.001. Altitude, ET-1, IL-6, and SpO2 were all univariate predictors of AMS. On multivariate analysis, ET-1 (p = 0.002) and reducing SpO2 (p = 0.02) remained as the only independent predictors (overall r(2) = 0.16; p < 0.001) of AMS. ET-1 (p = 03) and SpO2 were (p = 0.01) also independent predictors of severe AMS (overall r(2) = 0.19; p < 0.001). CONCLUSIONS HA leads to endothelial activation and an inflammatory response. The rise in ET-1 and IL-6 is heavily influenced by the degree of exercise and hypoxia. ET-1 is an independent predictor of both AMS and its severity.
Collapse
Affiliation(s)
- Christopher John Boos
- 1 Department of Cardiology, Poole Hospital NHS Foundation Trust , Poole, Dorset, United Kingdom .,2 Department of Postgraduate Medical Education, Bournemouth University , Bournemouth, United Kingdom
| | - David R Woods
- 3 Northumbria and Newcastle NHS Trusts, Wansbeck General and Royal Victoria Infirmary , Newcastle, United Kingdom .,4 Defence Medical Services , Lichfield, United Kingdom .,5 University of Newcastle , Newcastle upon Tyne, United Kingdom .,6 Leeds Beckett University , Leeds, United Kingdom
| | | | | | | | - Adrian J Mellor
- 4 Defence Medical Services , Lichfield, United Kingdom .,7 Singulex, Inc. , Alameda, California.,8 James Cook University Hospital , Middlesbrough, United Kingdom
| |
Collapse
|
9
|
Hazlerigg A, Woods DR, Mellor AJ. Incidence of acute mountain sickness in UK Military Personnel on Mount Kenya. J ROY ARMY MED CORPS 2015; 162:465-469. [PMID: 26604255 DOI: 10.1136/jramc-2015-000524] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2015] [Revised: 09/17/2015] [Accepted: 10/03/2015] [Indexed: 11/04/2022]
Abstract
BACKGROUND Acute mountain sickness (AMS) is a common problem of trekkers to high altitude. The UK military train at high altitude through adventurous training (AT) or as exercising troops. The ascent of Point Lenana at 4985 m on Mount Kenya is frequently attempted on AT. This study sought to establish the incidence of AMS within this population, to aid future planning for military activities at altitude. METHODS A voluntary questionnaire was distributed to all British Army Training Unit Kenya based expeditions attempting to ascend Mount Kenya during the period from February to April 2014. The questionnaire included twice daily Lake Louise and Borg (perceived exertion scale) self-scoring. All expeditions were planned around a 5-day schedule, which included reserve time for acclimatisation, illness and inclement weather. RESULTS Data were collected on 47 participants, 70% of whom reached the summit of Point Lenana. 62% (29/47) self-reported AMS (defined as Lake Louise score (LLS) ≥3) on at least one occasion during the ascent, and 34% (10/29) suffered severe AMS (LLS ≥6). Those who attempted the climb within 2 weeks of arrival in Kenya had a higher incidence of AMS (12/15 (80%) vs 17/32 (53%), p=0.077). Participants recording a high Borg score were significantly more likely to develop AMS (16/18 vs 9/21, p=0.003). CONCLUSIONS This represents the first informative dataset for Mount Kenya ascents and altitude. The incidence of AMS during AT on Mount Kenya using this ascent profile is high. Adapting the current ascent profile, planning the ascent after time in country and reducing perceived exertion during the trek may reduce the incidence of AMS.
Collapse
Affiliation(s)
- Antonia Hazlerigg
- Defence Medical Services, Royal Centre for Defence Medicine, Birmingham Research Park, Birmingham, UK.,Department of Emergency Medicine, Royal Infirmary Edinburgh, Edinburgh, UK
| | - D R Woods
- Defence Medical Services, Royal Centre for Defence Medicine, Birmingham Research Park, Birmingham, UK.,Carnegie Institute of Sport, Physical Activity and Leisure, Leeds Beckett University, Leeds, UK.,Department of Medicine, Royal Victoria Infirmary, Newcastle Hospitals NHS Foundation Trust, Newcastle, UK
| | - A J Mellor
- Defence Medical Services, Royal Centre for Defence Medicine, Birmingham Research Park, Birmingham, UK.,Carnegie Institute of Sport, Physical Activity and Leisure, Leeds Beckett University, Leeds, UK.,Academic Department of Anaesthesia and Critical Care, Royal Centre for Defence Medicine, Birmingham, UK
| |
Collapse
|
10
|
Shah NM, Hussain S, Cooke M, O’Hara JP, Mellor A. Wilderness medicine at high altitude: recent developments in the field. Open Access J Sports Med 2015; 6:319-28. [PMID: 26445563 PMCID: PMC4590685 DOI: 10.2147/oajsm.s89856] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Travel to high altitude is increasingly popular. With this comes an increased incidence of high-altitude illness and therefore an increased need to improve our strategies to prevent and accurately diagnose these. In this review, we provide a summary of recent advances of relevance to practitioners who may be advising travelers to altitude. Although the Lake Louise Score is now widely used as a diagnostic tool for acute mountain sickness (AMS), increasing evidence questions the validity of doing so, and of considering AMS as a single condition. Biomarkers, such as brain natriuretic peptide, are likely correlating with pulmonary artery systolic pressure, thus potential markers of the development of altitude illness. Established drug treatments include acetazolamide, nifedipine, and dexamethasone. Drugs with a potential to reduce the risk of developing AMS include nitrate supplements, propagators of nitric oxide, and supplemental iron. The role of exercise in the development of altitude illness remains hotly debated, and it appears that the intensity of exercise is more important than the exercise itself. Finally, despite copious studies demonstrating the value of preacclimatization in reducing the risk of altitude illness and improving performance, an optimal protocol to preacclimatize an individual remains elusive.
Collapse
Affiliation(s)
- Neeraj M Shah
- Division of Asthma, Allergy and Lung Biology, King’s College London, UK
| | - Sidra Hussain
- School of Medicine, University College London, London, UK
| | - Mark Cooke
- Research Institute for Sport, Physical Activity and Leisure, Leeds Beckett University, Leeds, UK
| | - John P O’Hara
- Research Institute for Sport, Physical Activity and Leisure, Leeds Beckett University, Leeds, UK
| | - Adrian Mellor
- Research Institute for Sport, Physical Activity and Leisure, Leeds Beckett University, Leeds, UK
- Academic Department of Military Anaesthesia and Critical Care, Royal Centre for Defence Medicine, Birmingham, UK
| |
Collapse
|