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Wu Y, Zhao W, Liu B, Zhang J, Zhong Z, Zhou S, Xie J, Gao Y, Li P, Chen J. Assessment of Acute Mountain Sickness: Comparing the Chinese AMS Score to the Lake Louise Score. High Alt Med Biol 2024; 25:164-173. [PMID: 38602430 DOI: 10.1089/ham.2023.0033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/12/2024] Open
Abstract
Wu, Yu, Wenqi Zhao, Bao Liu, Jianyang Zhang, Zhifeng Zhong, Simin Zhou, Jiaxin Xie, Yuqi Gao, Peng Li, and Jian Chen. Assessment of Acute Mountain Sickness: Comparing the Chinese Ams Score to the Lake Louise Score. High Alt Med Biol 25:164-173, 2024. Objective: To compare the ability of the Chinese AMS Score (CAS) to detect acute mountain sickness (AMS) using the 2018 version of the Lake Louise Score (LLS) as reference. Methods: After flying from Chengdu (altitude: 500 m) to Lhasa (3,658 m), 2,486 young men completed a questionnaire. The questionnaire contained LLS and CAS items. An LLS ≥3 and/or a CAS ≥cutoff were used as the criteria for AMS. Hierarchical cluster analysis and two-step cluster analysis were used to investigate relationships between the symptoms. Results: AMS incidence rates were 33.8% (n = 840) with the LLS and 59.3% (n = 1,473) with the CAS (χ2 = 872.5, p < 0.001). The LLS and CAS had a linear relationship (orthogonal regression, Pearson r = 0.91, p < 0.001). With the LLS as the standard, the CAS had high diagnostic accuracy (area under the curve = 0.95, 95% confidence interval: 0.94-0.96). However, with the CAS, 25.5% (n = 633) more participants were labeled as having AMS than with the LLS (false positives). Two clusters were identified: one with headache only (419 participants, 66.2%) and one without headache but with other symptoms (214 participants, 33.8%). Reducing the weight of headache in the CAS allowed to align CAS and LLS. Conclusion: In comparison to the LLS, the CAS has a sensitivity close to 100% but lacks specificity given the high rate of false positives. The different weight of headaches may be the main reason for the discrepancy.
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Affiliation(s)
- Yu Wu
- Department of High Altitude Operational Medicine College of High Altitude Military Medicine, Army Medical University, Chongqing, People's Republic of China
- High Altitude Medical Research Center, PLA, Army Medical University, Chongqing, People's Republic of China
- Key Laboratory of Extreme Environmental Medicine, Ministry of Education, Army Medical University, Chongqing, People's Republic of China
| | - Wenqi Zhao
- Institute of Medicine and Equipment for High Altitude Region, College of High Altitude Military Medicine, Army Medical University, Chongqing, People's Republic of China
- High Altitude Medical Research Center, PLA, Army Medical University, Chongqing, People's Republic of China
- Key Laboratory of Extreme Environmental Medicine, Ministry of Education, Army Medical University, Chongqing, People's Republic of China
| | - Bao Liu
- Institute of Medicine and Equipment for High Altitude Region, College of High Altitude Military Medicine, Army Medical University, Chongqing, People's Republic of China
- High Altitude Medical Research Center, PLA, Army Medical University, Chongqing, People's Republic of China
- Key Laboratory of Extreme Environmental Medicine, Ministry of Education, Army Medical University, Chongqing, People's Republic of China
| | - Jianyang Zhang
- Institute of Medicine and Equipment for High Altitude Region, College of High Altitude Military Medicine, Army Medical University, Chongqing, People's Republic of China
- High Altitude Medical Research Center, PLA, Army Medical University, Chongqing, People's Republic of China
- Key Laboratory of Extreme Environmental Medicine, Ministry of Education, Army Medical University, Chongqing, People's Republic of China
| | - Zhifeng Zhong
- Department of High Altitude Operational Medicine College of High Altitude Military Medicine, Army Medical University, Chongqing, People's Republic of China
- High Altitude Medical Research Center, PLA, Army Medical University, Chongqing, People's Republic of China
- Key Laboratory of Extreme Environmental Medicine, Ministry of Education, Army Medical University, Chongqing, People's Republic of China
| | - Simin Zhou
- Department of High Altitude Operational Medicine College of High Altitude Military Medicine, Army Medical University, Chongqing, People's Republic of China
- High Altitude Medical Research Center, PLA, Army Medical University, Chongqing, People's Republic of China
- Key Laboratory of Extreme Environmental Medicine, Ministry of Education, Army Medical University, Chongqing, People's Republic of China
| | - Jiaxin Xie
- Department of High Altitude Operational Medicine College of High Altitude Military Medicine, Army Medical University, Chongqing, People's Republic of China
- High Altitude Medical Research Center, PLA, Army Medical University, Chongqing, People's Republic of China
- Key Laboratory of Extreme Environmental Medicine, Ministry of Education, Army Medical University, Chongqing, People's Republic of China
| | - Yuqi Gao
- Institute of Medicine and Equipment for High Altitude Region, College of High Altitude Military Medicine, Army Medical University, Chongqing, People's Republic of China
- High Altitude Medical Research Center, PLA, Army Medical University, Chongqing, People's Republic of China
- Key Laboratory of Extreme Environmental Medicine, Ministry of Education, Army Medical University, Chongqing, People's Republic of China
| | - Peng Li
- Department of High Altitude Operational Medicine College of High Altitude Military Medicine, Army Medical University, Chongqing, People's Republic of China
- High Altitude Medical Research Center, PLA, Army Medical University, Chongqing, People's Republic of China
- Key Laboratory of Extreme Environmental Medicine, Ministry of Education, Army Medical University, Chongqing, People's Republic of China
| | - Jian Chen
- Institute of Medicine and Equipment for High Altitude Region, College of High Altitude Military Medicine, Army Medical University, Chongqing, People's Republic of China
- High Altitude Medical Research Center, PLA, Army Medical University, Chongqing, People's Republic of China
- Key Laboratory of Extreme Environmental Medicine, Ministry of Education, Army Medical University, Chongqing, People's Republic of China
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Luks AM, Beidleman BA, Freer L, Grissom CK, Keyes LE, McIntosh SE, Rodway GW, Schoene RB, Zafren K, Hackett PH. Wilderness Medical Society Clinical Practice Guidelines for the Prevention, Diagnosis, and Treatment of Acute Altitude Illness: 2024 Update. Wilderness Environ Med 2024; 35:2S-19S. [PMID: 37833187 DOI: 10.1016/j.wem.2023.05.013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2022] [Revised: 04/14/2023] [Accepted: 05/17/2023] [Indexed: 10/15/2023]
Abstract
To provide guidance to clinicians about best practices, the Wilderness Medical Society (WMS) convened an expert panel to develop evidence-based guidelines for prevention, diagnosis, and treatment of acute mountain sickness, high altitude cerebral edema, and high altitude pulmonary edema. Recommendations are graded based on the quality of supporting evidence and the balance between the benefits and risks/burdens according to criteria put forth by the American College of Chest Physicians. The guidelines also provide suggested approaches for managing each form of acute altitude illness that incorporate these recommendations as well as recommendations on how to approach high altitude travel following COVID-19 infection. This is an updated version of the original WMS Consensus Guidelines for the Prevention and Treatment of Acute Altitude Illness published in Wilderness & Environmental Medicine in 2010 and the subsequently updated WMS Practice Guidelines for the Prevention and Treatment of Acute Altitude Illness published in 2014 and 2019.
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Affiliation(s)
- Andrew M Luks
- Division of Pulmonary, Critical Care and Sleep Medicine, University of Washington, Seattle, WA
| | - Beth A Beidleman
- Military Performance Division, US Army Research Institute of Environmental Medicine, Natick, MA
| | - Luanne Freer
- Everest ER, Himalayan Rescue Association, Kathmandu, Nepal
| | - Colin K Grissom
- Pulmonary and Critical Care Medicine, Intermountain Healthcare and the University of Utah, Salt Lake City, UT
| | - Linda E Keyes
- Department of Emergency Medicine, Section of Wilderness Medicine, University of Colorado, Anschutz Medical Campus, Aurora, CO
| | - Scott E McIntosh
- Department of Emergency Medicine, University of Utah Health, Salt Lake City, UT
| | - George W Rodway
- Department of Family Medicine-Sports Medicine, University of Nevada, Reno School of Medicine, Reno, NV
| | - Robert B Schoene
- Division of Pulmonary and Critical Care Medicine, Sound Physicians, St. Mary's Medical Center and Division of Pulmonary and Critical Care Medicine, University of California, San Francisco, San Francisco, CA
| | - Ken Zafren
- Department of Emergency Medicine, Stanford University School of Medicine, Stanford, CA
- Himalayan Rescue Association, Kathmandu, Nepal
| | - Peter H Hackett
- Altitude Research Center, Division of Pulmonary Sciences and Critical Care Medicine, Department of Medicine, University of Colorado Anschutz Medical Campus, Aurora, CO
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Bhandari SS. Letter to the Editor: Sensitivity and Specificity of the Lake Louise Score: What Should We Focus On? High Alt Med Biol 2023; 24:337-338. [PMID: 37578468 DOI: 10.1089/ham.2023.0079] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/15/2023] Open
Affiliation(s)
- Sanjeeb S Bhandari
- Mountain Medicine Society of Nepal, Kathmandu, Nepal
- Collaboration for Emergency Care, Kathmandu, Nepal
- Emergency Department, UPMC Western Maryland Health, Cumberland, Maryland, USA
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Anderson PJ, Wood-Wentz CM, Bailey KR, Johnson BD. Objective Versus Self-Reported Sleep Quality at High Altitude. High Alt Med Biol 2023; 24:144-148. [PMID: 29172727 DOI: 10.1089/ham.2017.0078] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Anderson, Paul J., Christina M. Wood-Wentz, Kent R. Bailey, and Bruce D. Johnson. Objective versus self-reported sleep quality at high altitude. High Alt Med Biol. 24:144-148, 2023. Background: Previous studies have found little relationship between polysomnography and a diagnosis of acute mountain sickness (AMS) using the Lake Louise Symptom Questionnaire (LLSQ). The correlation between sleep question responses on the LLSQ and polysomnography results has not been explored. We compared LLSQ sleep responses and polysomnography data from our previous study of workers rapidly transported to the South Pole. Methods: Sixty-three subjects completed a 3-hour flight from sea level to the South Pole (3200 m, 9800 ft). Participants completed limited overnight polysomnography on their first night and completed LLSQ upon awakening. We compared polysomnography results at the South Pole with sleep question responses on the LLSQ to assess their degree of correspondence. Results: Twenty-two (30%) individuals reported no sleep problems whereas 20 (32%) reported some problems and 20 (33%) individuals reported poor sleep and 1 reported no sleep (n = 1). Median sleep efficiency was (94%) among response groups and mean overnight oxygen saturation was 81%. Median apnea hypopnea index (AHI; events/hour) was 10.2 in those who reported no problems sleeping, 5.1 in those reporting some problems sleeping, and 13.7 in those who reported poor sleep. These differences were not statistically significant. Conclusion: Self-reported sleep quality varied but there were no associated significant differences in sleep efficiency, overnight oxygen saturation, nor AHI. Studies that explore the role of objective sleep quality in the development of AMS should remove the sleep question on the LLSQ from AMS scoring algorithms.
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Affiliation(s)
- Paul J Anderson
- Human Integrative and Environmental Physiology Laboratory, Mayo Clinic, Rochester, Minnesota
| | - Christina M Wood-Wentz
- Division of Biomedical Statistics and Informatics, Department of Health Sciences Research, Mayo Clinic, Rochester, Minnesota
| | - Kent R Bailey
- Division of Biomedical Statistics and Informatics, Department of Health Sciences Research, Mayo Clinic, Rochester, Minnesota
| | - Bruce D Johnson
- Human Integrative and Environmental Physiology Laboratory, Mayo Clinic, Rochester, Minnesota
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Woolcott OO. The Lake Louise Acute Mountain Sickness Score: Still a Headache. High Alt Med Biol 2021; 22:351-352. [PMID: 34905394 DOI: 10.1089/ham.2021.0110] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Affiliation(s)
- Orison O Woolcott
- Institute for Globally Distributed Open Research and Education (IGDORE), Los Angeles, California, USA.,Ronin Institute, Montclair, New Jersey, USA
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Garrido E, Botella de Maglia J, Castillo O. Acute, subacute and chronic mountain sickness. Rev Clin Esp 2021; 221:481-490. [PMID: 34583826 DOI: 10.1016/j.rceng.2019.12.009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 12/16/2019] [Indexed: 11/29/2022]
Abstract
More than 100 million people ascend to high mountainous areas worldwide every year. At nonextreme altitudes (<5500m), 10-85% of these individuals are affected by acute mountain sickness, the most common disease induced by mild-moderate hypobaric hypoxia. Approximately 140 million individuals live permanently at heights of 2500-5500m, and up to 10% of them are affected by the subacute form of mountain sickness (high-altitude pulmonary hypertension) or the chronic form (Monge's disease), the latter of which is especially common in Andean ethnicities. This review presents the most relevant general concepts of these 3 clinical variants, which can be incapacitating and can result in complications and become life-threatening. Proper prevention, diagnosis, treatment and management of these conditions in a hostile environment such as high mountains are therefore essential.
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Affiliation(s)
- E Garrido
- Servicio de Hipobaria y Fisiología Biomédica, Universidad de Barcelona, L'Hospitalet de Llobregat, Barcelona, Spain; Instituto de Estudios de Medicina de Montaña (IEMM), Barcelona, Spain.
| | - J Botella de Maglia
- Servicio de Medicina Intensiva, Hospital Universitario y Politécnico La Fe, Valencia, Spain; Instituto de Estudios de Medicina de Montaña (IEMM), Barcelona, Spain
| | - O Castillo
- Instituto Nacional de Biología Andina, Universidad Nacional Mayor de San Marcos, Lima, Peru
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Chen R, Wang Y, Zhang C, Luo X, Yang J, Liu C, Huang L. Assessment of Acute Mountain Sickness Using 1993 and 2018 Versions of the Lake Louise Score in a Large Chinese Cohort. High Alt Med Biol 2021; 22:362-368. [PMID: 34558963 DOI: 10.1089/ham.2021.0031] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Chen, Renzheng, Yong Wang, Chen Zhang, Xiaolin Luo, Jie Yang, Chuan Liu, and Lan Huang. Assessment of acute mountain sickness using 1993 and 2018 versions of the Lake Louise Score in a large Chinese cohort. High Alt Med Biol. 22:362-368, 2021. Background: This study uses Lake Louise Score (LLS) in its original (LLS1993) and new (LLS2018) versions to assess acute mountain sickness (AMS) and aims to provide more clinical information about the AMS scoring system. Methods: We enrolled 1,026 male Chinese soldiers who traveled from an altitude of 500 to 3,700 m by airplane in 2.5 hours. We observed each subject's symptoms after arrival at 3,700 m in 24 and 48 hours. Each item was dropped from LLS1993 to evaluate its sensitivity and effect on AMS diagnosis. The relationship between each symptom and AMS was assessed by correlation analysis. Exploratory and confirmatory factor analyses evaluated the factor structure of LLS, while the ordinal alpha coefficient was calculated to determine its internal consistency. Results: Four hundred fifty-nine subjects were not followed up on day 2. We defined two observed cohorts (cohort 1, n = 1,026 and cohort 2, n = 567). Headache was the most common symptom in 24 hours, while sleep disturbance was the fourth-most common symptom at 24 hours and the most common symptom at 48 hours. When we dropped gastrointestinal symptoms, the drop rate was lowest in each situation (1.0% in cohort 1, 1.3% in cohort 2 at 24 hours, and 5.7% in cohort 2 at 48 hours, respectively). The incidence of AMS decreased from 18.4% at 24 hours to 36.4% at 48 hours when lost sleep disturbance in cohort 2. Moreover, the statistical method of Mantel/Haenszel square test was used for correlation analysis and the results showed a correlation between sleep disturbance and AMS. Besides, both LLS1993 and LLS2018 had acceptable internal consistencies, and all items had good loading coefficients in LLS1993. Conclusions: We have demonstrated that there could be an association between sleep disturbance and AMS diagnosis. Both LLS1993 and LLS2018 applied to young Chinese men.
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Affiliation(s)
- Renzheng Chen
- Institute of Cardiovascular Diseases of PLA, The Second Affiliated Hospital of Third Military Medical University (Army Medical University), Chongqing, China.,Department of Cardiology, The Second Affiliated Hospital of Third Military Medical University (Army Medical University), Chongqing, China
| | - Yong Wang
- Institute of Cardiovascular Diseases of PLA, The Second Affiliated Hospital of Third Military Medical University (Army Medical University), Chongqing, China.,Department of Cardiology, The Second Affiliated Hospital of Third Military Medical University (Army Medical University), Chongqing, China
| | - Chen Zhang
- Institute of Cardiovascular Diseases of PLA, The Second Affiliated Hospital of Third Military Medical University (Army Medical University), Chongqing, China.,Department of Cardiology, The Second Affiliated Hospital of Third Military Medical University (Army Medical University), Chongqing, China
| | - Xiaolin Luo
- Institute of Cardiovascular Diseases of PLA, The Second Affiliated Hospital of Third Military Medical University (Army Medical University), Chongqing, China.,Department of Cardiology, The Second Affiliated Hospital of Third Military Medical University (Army Medical University), Chongqing, China
| | - Jie Yang
- Institute of Cardiovascular Diseases of PLA, The Second Affiliated Hospital of Third Military Medical University (Army Medical University), Chongqing, China.,Department of Cardiology, The Second Affiliated Hospital of Third Military Medical University (Army Medical University), Chongqing, China
| | - Chuan Liu
- Institute of Cardiovascular Diseases of PLA, The Second Affiliated Hospital of Third Military Medical University (Army Medical University), Chongqing, China.,Department of Cardiology, The Second Affiliated Hospital of Third Military Medical University (Army Medical University), Chongqing, China
| | - Lan Huang
- Institute of Cardiovascular Diseases of PLA, The Second Affiliated Hospital of Third Military Medical University (Army Medical University), Chongqing, China.,Department of Cardiology, The Second Affiliated Hospital of Third Military Medical University (Army Medical University), Chongqing, China
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Richalet JP, Julia C, Lhuissier FJ. Evaluation of the Lake Louise Score for Acute Mountain Sickness and Its 2018 Version in a Cohort of 484 Trekkers at High Altitude. High Alt Med Biol 2021; 22:353-361. [PMID: 34515528 DOI: 10.1089/ham.2020.0226] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Richalet, Jean-Paul, Chantal Julia, and François J. Lhuissier. Evaluation of the Lake Louise Score for acute mountain sickness and its 2018 version in a cohort of 484 trekkers at high altitude. High Alt Med Biol. 22:353-361, 2021. Background: The Lake Louise Score (LLS) is widely used in field studies and chamber studies for the diagnosis of Acute Mountain Sickness (AMS). This score aggregates symptoms that are nonspecific: headache, gastrointestinal symptoms, fatigue, dizziness and sleep disturbance can be due to a variety of causes unrelated to altitude hypoxia. The objectives of this study were to (1) reevaluate the need for a headache score >0 for the diagnosis of AMS, (2) evaluate the role of sleep disturbances, in relation with other symptoms, (3) evaluate the significance of dizziness. Materials and Methods: We analyzed LLS from 484 trekkers at high altitude. Among them, 212 suffered from moderate AMS (mAMS: 3 ≤ LLS < 6) and 115 from severe AMS (sAMS: LLS ≥ 6). Results: Cluster analysis of AMS revealed three main groups presenting the following symptoms: Group 1 includes 254 subjects who had less than 2 symptoms; Group 2 includes 137 subjects who had fatigue, sleep disturbance, and headache, corresponding to mAMS; Group 3 includes 93 subjects who had headache, fatigue, dizziness and sleep disturbance, corresponding to sAMS. A headache score of zero was found in 25% of mAMS and 5% of sAMS subjects. Only the absence of headache associated with the absence of fatigue was specific of absence of sAMS. In subjects with a dizziness score > 1, end-tidal partial pressure of carbon dioxide during a hypoxic exercise test was lower than that in subjects with a dizziness score < 2. Subjects with high ventilatory response to hypoxia may develop dizziness with high altitude exposure. Conclusion: (1) An isolated headache score > 0 should not be mandatory to define AMS, (2) sleep disruption contributes to the diagnosis of AMS, (3) gastrointestinal symptoms and dizziness are weaker contributors to the LLS, (4) dizziness might be linked to a hyperresponsiveness to hypoxia and not to AMS itself.
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Affiliation(s)
- Jean-Paul Richalet
- Université Sorbonne Paris Nord, UMR INSERM U1272 Hypoxie et Poumon, Bobigny, France.,Institut National du Sport, de l'Expertise et de la Performance, Pôle Médical, Paris, France
| | - Chantal Julia
- Assistance Publique-Hôpitaux de Paris, Hôpitaux Universitaires Paris-Seine-Saint-Denis, Paris, France.,Université Sorbonne Paris Nord, UMR INSERM U1153, Équipe de Recherche en Épidémiologie Nutritionnelle, Bobigny, France
| | - François J Lhuissier
- Université Sorbonne Paris Nord, UMR INSERM U1272 Hypoxie et Poumon, Bobigny, France.,Assistance Publique-Hôpitaux de Paris, Hôpitaux Universitaires Paris-Seine-Saint-Denis, Paris, France
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Zhang JH, Shen Y, Liu C, Yang J, Yang YQ, Zhang C, Bian SZ, Yu J, Gao XB, Zhang LP, Ke JB, Yuan FZY, Pan WX, Guo ZN, Huang L. EPAS1 and VEGFA gene variants are related to the symptoms of acute mountain sickness in Chinese Han population: a cross-sectional study. Mil Med Res 2020; 7:35. [PMID: 32718338 PMCID: PMC7385974 DOI: 10.1186/s40779-020-00264-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/06/2019] [Accepted: 07/14/2020] [Indexed: 12/27/2022] Open
Abstract
BACKGROUND More people ascend to high altitude (HA) for various activities, and some individuals are susceptible to HA illness after rapidly ascending from plains. Acute mountain sickness (AMS) is a general complaint that affects activities of daily living at HA. Although genomic association analyses suggest that single nucleotide polymorphisms (SNPs) are involved in the genesis of AMS, no major gene variants associated with AMS-related symptoms have been identified. METHODS In this cross-sectional study, 604 young, healthy Chinese Han men were recruited in June and July of 2012 in Chengdu, and rapidly taken to above 3700 m by plane. Basic demographic parameters were collected at sea level, and heart rate, pulse oxygen saturation (SpO2), systolic and diastolic blood pressure and AMS-related symptoms were determined within 18-24 h after arriving in Lhasa. AMS patients were identified according to the latest Lake Louise scoring system (LLSS). Potential associations between variant genotypes and AMS/AMS-related symptoms were identified by logistic regression after adjusting for potential confounders (age, body mass index and smoking status). RESULTS In total, 320 subjects (53.0%) were diagnosed with AMS, with no cases of high-altitude pulmonary edema or high-altitude cerebral edema. SpO2 was significantly lower in the AMS group than that in the non-AMS group (P = 0.003). Four SNPs in hypoxia-inducible factor-related genes were found to be associated with AMS before multiple hypothesis testing correction. The rs6756667 (EPAS1) was associated with mild gastrointestinal symptoms (P = 0.013), while rs3025039 (VEGFA) was related to mild headache (P = 0.0007). The combination of rs6756667 GG and rs3025039 CT/TT further increased the risk of developing AMS (OR = 2.70, P < 0.001). CONCLUSIONS Under the latest LLSS, we find that EPAS1 and VEGFA gene variants are related to AMS susceptibility through different AMS-related symptoms in the Chinese Han population; this tool might be useful for screening susceptible populations and predicting clinical symptoms leading to AMS before an individual reaches HA. TRIAL REGISTRATION Chinese Clinical Trial Registration, ChiCTR-RCS-12002232 . Registered 31 May 2012.
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Affiliation(s)
- Ji-Hang Zhang
- Institute of Cardiovascular Diseases, Department of Cardiology, Xinqiao Hospital, Army Medical University, Chongqing, 400037, China
| | - Yang Shen
- Institute of Cardiovascular Diseases, Department of Cardiology, Xinqiao Hospital, Army Medical University, Chongqing, 400037, China
| | - Chuan Liu
- Institute of Cardiovascular Diseases, Department of Cardiology, Xinqiao Hospital, Army Medical University, Chongqing, 400037, China
| | - Jie Yang
- Institute of Cardiovascular Diseases, Department of Cardiology, Xinqiao Hospital, Army Medical University, Chongqing, 400037, China
| | - Yuan-Qi Yang
- Institute of Cardiovascular Diseases, Department of Cardiology, Xinqiao Hospital, Army Medical University, Chongqing, 400037, China
| | - Chen Zhang
- Institute of Cardiovascular Diseases, Department of Cardiology, Xinqiao Hospital, Army Medical University, Chongqing, 400037, China
| | - Shi-Zhu Bian
- Institute of Cardiovascular Diseases, Department of Cardiology, Xinqiao Hospital, Army Medical University, Chongqing, 400037, China
| | - Jie Yu
- Institute of Cardiovascular Diseases, Department of Cardiology, Xinqiao Hospital, Army Medical University, Chongqing, 400037, China
| | - Xu-Bin Gao
- Institute of Cardiovascular Diseases, Department of Cardiology, Xinqiao Hospital, Army Medical University, Chongqing, 400037, China
| | - Lai-Ping Zhang
- Institute of Cardiovascular Diseases, Department of Cardiology, Xinqiao Hospital, Army Medical University, Chongqing, 400037, China
| | - Jing-Bin Ke
- Institute of Cardiovascular Diseases, Department of Cardiology, Xinqiao Hospital, Army Medical University, Chongqing, 400037, China
| | - Fang-Zheng-Yuan Yuan
- Institute of Cardiovascular Diseases, Department of Cardiology, Xinqiao Hospital, Army Medical University, Chongqing, 400037, China
| | - Wen-Xu Pan
- Institute of Cardiovascular Diseases, Department of Cardiology, Xinqiao Hospital, Army Medical University, Chongqing, 400037, China
| | - Zhi-Nian Guo
- Institute of Cardiovascular Diseases, Department of Cardiology, Xinqiao Hospital, Army Medical University, Chongqing, 400037, China
| | - Lan Huang
- Institute of Cardiovascular Diseases, Department of Cardiology, Xinqiao Hospital, Army Medical University, Chongqing, 400037, China.
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10
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Moore J, MacInnis MJ, Dallimore J, Wilkes M. The Lake Louise Score: A Critical Assessment of Its Specificity. High Alt Med Biol 2020; 21:237-242. [PMID: 32324448 DOI: 10.1089/ham.2019.0117] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Moore, James, Martin J. MacInnis, Jon Dallimore, and Matt Wilkes. The Lake Louise Score: A Critical Assessment of Its Specificity. High Alt Med Biol. 21:237-242, 2020. Introduction: The Lake Louise Score (LLS) has low specificity for diagnosing acute mountain sickness (AMS). As this tool is used for research and clinical decision making, it is important to understand the origins of this poor specificity. We reviewed AMS diagnoses in a population trekking at low altitude ("false positives") to critically assess LLS specificity. Method: We retrospectively analyzed data from a sample of 123 adolescents trekking at low altitude to establish the predominant causes of false-positive AMS diagnoses (1993 LLS criteria), separately removing each LLS component to assess its contribution to the final score. Exploratory factor analysis (EFA) was applied to the data to establish component patterns. Results: Removal of LLS components individually showed fatigue contributed slightly more to false-positive AMS diagnoses than sleep quality in this group. An EFA from morning data highlighted sleep quality as a stand-alone factor in the measurement of AMS. Although of smaller significance, an EFA of the evening data highlighted fatigue and headache as the stand-alone factor. Conclusion: Our findings not only supported the recent removal of sleep quality from the LLS, but also demonstrated that fatigue had an equal part to play in the misdiagnosis of AMS in this population. These data highlighted the poor specificity of the LLS and suggest that the measurement of illness at altitude undergo further review.
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Affiliation(s)
- James Moore
- International Diploma in Expedition and Wilderness Medicine, Royal College of Physicians and Surgeons of Glasgow, Glasgow, United Kingdom
| | | | - Jon Dallimore
- Emergency Medicine, Bristol Royal Infirmary, Bristol, United Kingdom
| | - Matt Wilkes
- Extreme Environments Laboratory, University of Portsmouth, Portsmouth, United Kingdom
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Garrido E, Botella de Maglia J, Castillo O. Acute, subacute and chronic mountain sickness. Rev Clin Esp 2020; 221:S0014-2565(20)30064-3. [PMID: 32197780 DOI: 10.1016/j.rce.2019.12.013] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2019] [Accepted: 12/16/2019] [Indexed: 11/20/2022]
Abstract
More than 100 million people ascend to high mountainous areas worldwide every year. At nonextreme altitudes (<5500 m), 10-85% of these individuals are affected by acute mountain sickness, the most common disease induced by mild-moderate hypobaric hypoxia. Approximately 140 million individuals live permanently at heights of 2500-5500 m, and up to 10% of them are affected by the subacute form of mountain sickness (high-altitude pulmonary hypertension) or the chronic form (Monge's disease), the latter of which is especially common in Andean ethnicities. This review presents the most relevant general concepts of these 3 clinical variants, which can be incapacitating and can result in complications and become life-threatening. Proper prevention, diagnosis, treatment and management of these conditions in a hostile environment such as high mountains are therefore essential.
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Affiliation(s)
- E Garrido
- Servicio de Hipobaria y Fisiología Biomédica, Universidad de Barcelona, L'Hospitalet de Llobregat, Barcelona, España; Instituto de Estudios de Medicina de Montaña (IEMM), Barcelona, España.
| | - J Botella de Maglia
- Servicio de Medicina Intensiva, Hospital Universitario y Politécnico La Fe, Valencia, España; Instituto de Estudios de Medicina de Montaña (IEMM), Barcelona, España
| | - O Castillo
- Instituto Nacional de Biología Andina, Universidad Nacional Mayor de San Marcos, Lima, Perú
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Prospective Double-Blinded Randomized Field-Based Clinical Trial of Metoclopramide and Ibuprofen for the Treatment of High Altitude Headache and Acute Mountain Sickness. Wilderness Environ Med 2020; 31:38-43. [PMID: 32057631 DOI: 10.1016/j.wem.2019.11.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2019] [Revised: 10/29/2019] [Accepted: 11/06/2019] [Indexed: 10/25/2022]
Abstract
INTRODUCTION High altitude headache (HAH) and acute mountain sickness (AMS) are common pathologies at high altitudes. There are similarities between AMS and migraine headaches, with nausea being a common symptom. Several studies have shown ibuprofen can be effective for AMS prophylaxis, but few have addressed treatment. Metoclopramide is commonly administered for migraine headaches but has not been evaluated for HAH or AMS. We aimed to evaluate metoclopramide and ibuprofen for treatment of HAH and AMS. METHODS We performed a prospective, double-blinded, randomized, field-based clinical trial of metoclopramide and ibuprofen for the treatment of HAH and AMS in 47 adult subjects in the Mount Everest region of Nepal. Subjects received either 400 mg ibuprofen or 10 mg metoclopramide in a 1-time dose. Lake Louise Score (LLS) and visual analog scale of symptoms were measured before and at 30, 60, and 120 min after treatment. RESULTS Subjects in both the metoclopramide and ibuprofen arms reported reduced headache severity and nausea compared to pretreatment values at 120 min. The ibuprofen group reported 22 mm reduction in headache and 6 mm reduction in nausea on a 100 mm visual analog scale at 120 min. The metoclopramide group reported 23 mm reduction in headache and 14 mm reduction in nausea. The ibuprofen group reported an average 3.5-point decrease on LLS, whereas the metoclopramide group reported an average 2.0-point decrease on LLS at 120 min. CONCLUSIONS Metoclopramide and ibuprofen may be effective alternative treatment options in HAH and AMS, especially for those patients who additionally report nausea.
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Estoppey J, Léger B, Vuistiner P, Sartori C, Kayser B. Low- and High-Altitude Cortisol Awakening Responses Differ Between AMS-Prone and AMS-Resistant Mountaineers. High Alt Med Biol 2019; 20:344-351. [DOI: 10.1089/ham.2019.0035] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Affiliation(s)
- Jan Estoppey
- Institute of Sport Sciences, Synathlon, Uni-Centre, Lausanne, Switzerland
| | - Bertrand Léger
- Department of Medical Research, Romandie Clinic for Rehabilitation, Sion, Switzerland
| | - Philippe Vuistiner
- Department of Medical Research, Romandie Clinic for Rehabilitation, Sion, Switzerland
| | - Claudio Sartori
- Department of Internal Medicine, University Hospital, Lausanne, Switzerland
| | - Bengt Kayser
- Institute of Sport Sciences, Synathlon, Uni-Centre, Lausanne, Switzerland
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Lipman GS, Jurkiewicz C, Winstead-Derlega C, Navlyt A, Burns P, Walker A, Phillips C, Reilly A, Burnier A, Romero J, Warner K, Hackett P. Day of Ascent Dosing of Acetazolamide for Prevention of Acute Mountain Sickness. High Alt Med Biol 2019; 20:271-278. [DOI: 10.1089/ham.2019.0007] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Affiliation(s)
- Grant S. Lipman
- Department of Emergency Medicine, Stanford University School of Medicine, Stanford, California
| | - Carrie Jurkiewicz
- Department of Emergency Medicine, Stanford University School of Medicine, Stanford, California
| | | | - Andrew Navlyt
- Stanford University Emergency Medicine Residency, Stanford University School of Medicine, Stanford, California
| | - Patrick Burns
- Department of Emergency Medicine, Stanford University School of Medicine, Stanford, California
| | - Anne Walker
- Department of Emergency Medicine, Stanford University School of Medicine, Stanford, California
| | - Caleb Phillips
- Department of Computational Science, University of Colorado, Boulder, Boulder, Colorado
| | - Aaron Reilly
- Department of Emergency Medicine, University of New Mexico School of Medicine, Albuquerque, New Mexico
| | - Andre Burnier
- Stanford University Emergency Medicine Residency, Stanford University School of Medicine, Stanford, California
| | - Joseph Romero
- Stanford University Emergency Medicine Residency, Stanford University School of Medicine, Stanford, California
| | - Keiran Warner
- Stanford University Emergency Medicine Residency, Stanford University School of Medicine, Stanford, California
| | - Peter Hackett
- Altitude Research Center, Department of Emergency Medicine, University of Colorado Anschutz Medical Campus, Aurora, Colorado
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The onset of sleep disturbances and their associations with anxiety after acute high-altitude exposure at 3700 m. Transl Psychiatry 2019; 9:175. [PMID: 31332159 PMCID: PMC6646382 DOI: 10.1038/s41398-019-0510-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/31/2018] [Revised: 04/30/2019] [Accepted: 05/31/2019] [Indexed: 11/22/2022] Open
Abstract
Sleep disturbances and psychiatric repercussions pose great challenges at high altitude; however, few studies have investigated sleep disturbance and anxiety profiles and their associations after acute exposure in consecutive patients. Thus, we aimed to study the profiles of sleep disturbances in consecutive patients after high-altitude exposure and the association of such disturbances with anxiety. A total of 668 participants were recruited at sea level and 3700 m. The trials were performed at sea level (1 week prior to a 2-h flight to a high-altitude destination) and at 3700 m (24, 72, and 168 h). Sleep disturbances were assessed by self-reported sleep patterns and scores on the Athens Insomnia Scale (AIS). State anxiety was assessed using the Self-Rating Anxiety Scale (SAS). In our study, the incidence of sleep disturbances increased significantly after acute high-altitude exposure (65.3%, 434/668) and then gradually decreased after 72 h (50%, 141/282) and 168 h (44%, 124/282). The sleep assessments AIS [2.0 (4.0) vs. 4.0 (5.0)] and ESS [4.0 (4.0) vs. 5.0 (5.0)] increased significantly (p < 0.05). Also, the SAS increased significantly from 26.25 (3.75) to 28.75 (7.5). The SAS was significantly high in sleep disturbance group [31.25 (7.5) vs. 27.5 (5), p < 0.001] than in the non-sleep- disturbance group. The baseline SAS and AIS scores were significantly higher in participants with sleep disturbances than in those without (p < 0.01). Age, baseline insomnia, sleepiness, fatigue, and higher SAS were predictors of sleep disturbances in univariate regression (all p values < 0.05). However, only an older age (p = 0.045) and a higher baseline SAS (p = 0.018) remained independent predictors of sleep disturbances. Our findings indicated that acute high-altitude exposure triggers the onset of sleep disturbances, which are closely associated with anxiety. Furthermore, baseline state anxiety and age are independent predictors of sleep disturbances at high altitude.
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RMSEA, CFI, and TLI in structural equation modeling with ordered categorical data: The story they tell depends on the estimation methods. Behav Res Methods 2019; 51:409-428. [PMID: 29869222 DOI: 10.3758/s13428-018-1055-2] [Citation(s) in RCA: 378] [Impact Index Per Article: 75.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
In structural equation modeling, application of the root mean square error of approximation (RMSEA), comparative fit index (CFI), and Tucker-Lewis index (TLI) highly relies on the conventional cutoff values developed under normal-theory maximum likelihood (ML) with continuous data. For ordered categorical data, unweighted least squares (ULS) and diagonally weighted least squares (DWLS) based on polychoric correlation matrices have been recommended in previous studies. Although no clear suggestions exist regarding the application of these fit indices when analyzing ordered categorical variables, practitioners are still tempted to adopt the conventional cutoff rules. The purpose of our research was to answer the question: Given a population polychoric correlation matrix and a hypothesized model, if ML results in a specific RMSEA value (e.g., .08), what is the RMSEA value when ULS or DWLS is applied? CFI and TLI were investigated in the same fashion. Both simulated and empirical polychoric correlation matrices with various degrees of model misspecification were employed to address the above question. The results showed that DWLS and ULS lead to smaller RMSEA and larger CFI and TLI values than does ML for all manipulated conditions, regardless of whether or not the indices are scaled. Applying the conventional cutoffs to DWLS and ULS, therefore, has a pronounced tendency not to discover model-data misfit. Discussions regarding the use of RMSEA, CFI, and TLI for ordered categorical data are given.
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17
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The influence of hypoxia and prolonged exercise on attentional performance at high and extreme altitudes: A pilot study. PLoS One 2018; 13:e0205285. [PMID: 30281651 PMCID: PMC6169942 DOI: 10.1371/journal.pone.0205285] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Accepted: 09/21/2018] [Indexed: 12/13/2022] Open
Abstract
Introduction Exposure to hypoxic conditions is reported to impair cognitive performance. Further, moderate physical exercise improves cognitive function, but little is known about the influence of exercise on cognitive function in hypoxia. Therefore, the current study aimed to examine the influence of hypoxia (HYP) and prolonged exercise (EX) on attentional performance. Methods A total of 80 participants (female: n = 29; male: n = 51) were assigned to four groups: HYP + EX (n = 15), HYP (n = 25), EX (n = 21) and normoxia (NOR) (n = 21). The Frankfurt Attention Inventory—2 (FAIR-2) was performed at four testing points (day 1, 14, 16 and 18) to assess attentional performance. All groups completed a pretest (D1) and a follow-up test (D18). In HYP + EX conditions, the cognitive task was performed in a hypoxic state after prolonged exercise (D14: 3950 m, D16: 5739 m) during a mountain climb on Mt. Kilimanjaro. Participants in HYP were tested under intermittent hypoxia at rest in a hypoxic chamber (D14: 3500 m, D16: 5800 m), and those in EX were tested under normoxia after prolonged exercise during a 7-day backcountry ski hiking tour. NOR was a control group, and participants completed all tests under normoxia and at rest. Results Hypoxia impaired the attentional functions performance value (PV) and continuity value (CV) for the HYP + EX (p = 0.000) and HYP (L: p = 0.025; K: p = 0.043) groups at 5739 m and 5800 m, respectively, but not the function quality value (QV). In contrast, the EX group did not exhibit changes in attentional function. Conclusion The current results suggest that attentional performance is impaired during extreme normobaric and hypobaric hypoxic exposure. We further conclude that greater cognitive impairment under hypobaric hypoxia during a mountain climb compared with normobaric hypoxia at rest is not caused by prolonged exercise, but may be influenced by other factors (e.g. low temperatures, dehydration, or sleep deprivation) that remain to be verified.
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18
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Pun M, Guadagni V, Bettauer KM, Drogos LL, Aitken J, Hartmann SE, Furian M, Muralt L, Lichtblau M, Bader PR, Rawling JM, Protzner AB, Ulrich S, Bloch KE, Giesbrecht B, Poulin MJ. Effects on Cognitive Functioning of Acute, Subacute and Repeated Exposures to High Altitude. Front Physiol 2018; 9:1131. [PMID: 30246787 PMCID: PMC6111975 DOI: 10.3389/fphys.2018.01131] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Accepted: 07/30/2018] [Indexed: 01/12/2023] Open
Abstract
Objective: Neurocognitive functions are affected by high altitude, however the altitude effects of acclimatization and repeated exposures are unclear. We investigated the effects of acute, subacute and repeated exposure to 5,050 m on cognition among altitude-naïve participants compared to control subjects tested at low altitude. Methods: Twenty-one altitude-naïve individuals (25.3 ± 3.8 years, 13 females) were exposed to 5,050 m for 1 week (Cycle 1) and re-exposed after a week of rest at sea-level (Cycle 2). Baseline (BL, 520 m), acute (Day 1, HA1) and acclimatization (Day 6, HA6, 5,050 m) measurements were taken in both cycles. Seventeen control subjects (24.9 ± 2.6 years, 12 females) were tested over a similar period in Calgary, Canada (1,103 m). The Reaction Time (RTI), Attention Switching Task (AST), Rapid Visual Processing (RVP) and One Touch Stockings of Cambridge (OTS) tasks were administered and outcomes were expressed in milliseconds/frequencies. Lake Louise Score (LLS) and blood oxygen saturation (SpO2) were recorded. Results: In both cycles, no significant changes were found with acute exposure on the AST total score, mean latency and SD. Significant changes were found upon acclimatization solely in the altitude group, with improved AST Mean Latency [HA1 (588 ± 92) vs. HA6 (526 ± 91), p < 0.001] and Latency SD [HA1 (189 ± 86) vs. HA6 (135 ± 65), p < 0.001] compared to acute exposure, in Cycle 1. No significant differences were present in the control group. When entering Acute SpO2 (HA1-BL), Acclimatization SpO2 (HA6-BL) and LLS score as covariates for both cycles, the effects of acclimatization on AST outcomes disappeared indicating that the changes were partially explained by SpO2 and LLS. The changes in AST Mean Latency [ΔBL (−61.2 ± 70.2) vs. ΔHA6 (−28.0 ± 58), p = 0.005] and the changes in Latency SD [ΔBL (−28.4 ± 41.2) vs. ΔHA6 (−0.2235 ± 34.8), p = 0.007] across the two cycles were smaller with acclimatization. However, the percent changes did not differ between cycles. These results indicate independent effects of altitude across repeated exposures. Conclusions: Selective and sustained attention are impaired at altitude and improves with acclimatization.The observed changes are associated, in part, with AMS score and SpO2. The gains in cognition with acclimatization during a first exposure are not carried over to repeated exposures.
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Affiliation(s)
- Matiram Pun
- Department of Physiology & Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Veronica Guadagni
- Department of Physiology & Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Department of Clinical Neuroscience, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,O'Brien Institute for Public Health, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Kaitlyn M Bettauer
- Department of Physiology & Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Department of Psychology, Faculty of Science, University of British Columbia, Vancouver, BC, Canada
| | - Lauren L Drogos
- Department of Physiology & Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Julie Aitken
- Biomedical Engineering Graduate Program, University of Calgary, Calgary, AB, Canada
| | - Sara E Hartmann
- Department of Physiology & Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Michael Furian
- Pulmonary Division, Sleep Disorders Centre and Pulmonary Hypertension Clinic, University Hospital Zürich, Zurich, Switzerland
| | - Lara Muralt
- Pulmonary Division, Sleep Disorders Centre and Pulmonary Hypertension Clinic, University Hospital Zürich, Zurich, Switzerland
| | - Mona Lichtblau
- Pulmonary Division, Sleep Disorders Centre and Pulmonary Hypertension Clinic, University Hospital Zürich, Zurich, Switzerland
| | - Patrick R Bader
- Pulmonary Division, Sleep Disorders Centre and Pulmonary Hypertension Clinic, University Hospital Zürich, Zurich, Switzerland
| | - Jean M Rawling
- Department of Family Medicine, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada
| | - Andrea B Protzner
- Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Department of Psychology, Faculty of Arts, University of Calgary, Calgary, AB, Canada
| | - Silvia Ulrich
- Pulmonary Division, Sleep Disorders Centre and Pulmonary Hypertension Clinic, University Hospital Zürich, Zurich, Switzerland
| | - Konrad E Bloch
- Pulmonary Division, Sleep Disorders Centre and Pulmonary Hypertension Clinic, University Hospital Zürich, Zurich, Switzerland
| | - Barry Giesbrecht
- Department of Psychological and Brain Sciences, Institute for Collaborative Biotechnologies, University of California, Santa Barbara, Santa Barbara, CA, United States
| | - Marc J Poulin
- Department of Physiology & Pharmacology, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Hotchkiss Brain Institute, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Department of Clinical Neuroscience, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,O'Brien Institute for Public Health, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Libin Cardiovascular Institute of Alberta, Cumming School of Medicine, University of Calgary, Calgary, AB, Canada.,Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada
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19
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Roach RC, Hackett PH, Oelz O, Bärtsch P, Luks AM, MacInnis MJ, Baillie JK. The 2018 Lake Louise Acute Mountain Sickness Score. High Alt Med Biol 2018; 19:4-6. [PMID: 29583031 DOI: 10.1089/ham.2017.0164] [Citation(s) in RCA: 279] [Impact Index Per Article: 46.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
Roach, Robert C., Peter H. Hackett, Oswald Oelz, Peter Bärtsch, Andrew M. Luks, Martin J. MacInnis, J. Kenneth Baillie, and The Lake Louise AMS Score Consensus Committee. The 2018 Lake Louise Acute Mountain Sickness Score. High Alt Med Biol 19:1-4, 2018.- The Lake Louise Acute Mountain Sickness (AMS) scoring system has been a useful research tool since first published in 1991. Recent studies have shown that disturbed sleep at altitude, one of the five symptoms scored for AMS, is more likely due to altitude hypoxia per se, and is not closely related to AMS. To address this issue, and also to evaluate the Lake Louise AMS score in light of decades of experience, experts in high altitude research undertook to revise the score. We here present an international consensus statement resulting from online discussions and meetings at the International Society of Mountain Medicine World Congress in Bolzano, Italy, in May 2014 and at the International Hypoxia Symposium in Lake Louise, Canada, in February 2015. The consensus group has revised the score to eliminate disturbed sleep as a questionnaire item, and has updated instructions for use of the score.
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Affiliation(s)
- Robert C Roach
- 1 Altitude Research Center, Division of Pulmonary Sciences and Critical Care Medicine, Department of Medicine, University of Colorado School of Medicine , Anschutz Medical Campus, Aurora, Colorado
| | - Peter H Hackett
- 1 Altitude Research Center, Division of Pulmonary Sciences and Critical Care Medicine, Department of Medicine, University of Colorado School of Medicine , Anschutz Medical Campus, Aurora, Colorado
| | - Oswald Oelz
- 2 Department of Internal Medicine, University of Zurich , Switzerland
| | - Peter Bärtsch
- 3 Department of Internal Medicine, University Hospital , Heidelberg, Germany
| | - Andrew M Luks
- 4 Division of Pulmonary, Critical Care and Sleep Medicine, Department of Medicine, University of Washington , Seattle, WA
| | | | - J Kenneth Baillie
- 6 Roslin Institute, University of Edinburgh , Easter Bush, Midlothian, United Kingdom .,7 Intensive Care Unit, Royal Infirmary Edinburgh, Edinburgh, United Kingdom
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Muza SR. Wearable physiological sensors and real-time algorithms for detection of acute mountain sickness. J Appl Physiol (1985) 2018; 124:557-563. [DOI: 10.1152/japplphysiol.00367.2017] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
This is a minireview of potential wearable physiological sensors and algorithms (process and equations) for detection of acute mountain sickness (AMS). Given the emerging status of this effort, the focus of the review is on the current clinical assessment of AMS, known risk factors (environmental, demographic, and physiological), and current understanding of AMS pathophysiology. Studies that have examined a range of physiological variables to develop AMS prediction and/or detection algorithms are reviewed to provide insight and potential technological roadmaps for future development of real-time physiological sensors and algorithms to detect AMS. Given the lack of signs and nonspecific symptoms associated with AMS, development of wearable physiological sensors and embedded algorithms to predict in the near term or detect established AMS will be challenging. Prior work using [Formula: see text], HR, or HRv has not provided the sensitivity and specificity for useful application to predict or detect AMS. Rather than using spot checks as most prior studies have, wearable systems that continuously measure SpO2 and HR are commercially available. Employing other statistical modeling approaches such as general linear and logistic mixed models or time series analysis to these continuously measured variables is the most promising approach for developing algorithms that are sensitive and specific for physiological prediction or detection of AMS.
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Affiliation(s)
- Stephen R. Muza
- Strategic Science Management Office, US Army Research Institute of Environmental Medicine, Natick, Massachusetts
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21
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Basnyat B. The potential usefulness of serum biomarkers in high-altitude medicine. J Travel Med 2018; 25:5099422. [PMID: 30239850 DOI: 10.1093/jtm/tay083] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2018] [Indexed: 01/20/2023]
Affiliation(s)
- B Basnyat
- Oxford University Clinical Research Unit-Patan Academy of Health Sciences, Lalitpur, Nepal. Center for Tropical Medicine and Global Health, University of Oxford, Oxford, UK
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Meier D, Collet TH, Locatelli I, Cornuz J, Kayser B, Simel DL, Sartori C. Does This Patient Have Acute Mountain Sickness?: The Rational Clinical Examination Systematic Review. JAMA 2017; 318:1810-1819. [PMID: 29136449 DOI: 10.1001/jama.2017.16192] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
IMPORTANCE Acute mountain sickness (AMS) affects more than 25% of individuals ascending to 3500 m (11 500 ft) and more than 50% of those above 6000 m (19 700 ft). AMS may progress from nonspecific symptoms to life-threatening high-altitude cerebral edema in less than 1% of patients. It is not clear how to best diagnose AMS. OBJECTIVE To systematically review studies assessing the accuracy of AMS diagnostic instruments, including the visual analog scale (VAS) score, which quantifies the overall feeling of sickness at altitude (VAS[O]; various thresholds), Acute Mountain Sickness-Cerebral score (AMS-C; ≥0.7 indicates AMS), and the clinical functional score (CFS; ≥2 indicates AMS) compared with the Lake Louise Questionnaire Score (LLQS; score of ≥5). DATA EXTRACTION AND SYNTHESIS Searches of MEDLINE and EMBASE from inception to May 2017 identified 1245 publications of which 91 were suitable for prevalence analysis (66 944 participants) and 14 compared at least 2 instruments (1858 participants) using a score of 5 or greater on the LLQS as a reference standard. To determine the prevalence of AMS for establishing the pretest probability of AMS, a random-effects meta-regression was performed based on the reported prevalence of AMS as a function of altitude. MAIN OUTCOMES AND MEASURES AMS prevalence, likelihood ratios (LRs), sensitivity, and specificity of screening instruments. RESULTS The final analysis included 91 articles (comprising 66 944 study participants). Altitude predicted AMS and accounted for 28% of heterogeneity between studies. For each 1000-m (3300-ft) increase in altitude above 2500 m (8200 ft), AMS prevalence increased 13% (95% CI, 9.5%-17%). Testing characteristics were similar for VAS(O), AMS-C, and CFS vs a score of 5 or greater on the LLQS (positive LRs: range, 3.2-8.2; P = .22 for comparisons; specificity range, 67%-92%; negative LRs: range, 0.30-0.36; P = .50 for comparisons; sensitivity range, 67%-82%). The CFS asks a single question: "overall if you had any symptoms, how did they affect your activity (ordinal scale 0-3)?" For CFS, moderate to severe reduction in daily activities had a positive LR of 3.2 (95% CI, 1.4-7.2) and specificity of 67% (95% CI, 37%-97%); no reduction to mild reduction in activities had a negative LR of 0.30 (95% CI, 0.22-0.39) and sensitivity of 82% (95% CI, 77%-87%). CONCLUSIONS AND RELEVANCE The prevalence of acute mountain sickness increases with higher altitudes. The visual analog scale for the overall feeling of sickness at altitude, Acute Mountain Sickness-Cerebral, and clinical functional score perform similarly to the Lake Louise Questionnaire Score using a score of 5 or greater as a reference standard. In clinical and travel settings, the clinical functional score is the simplest instrument to use. Clinicians evaluating high-altitude travelers who report moderate to severe limitations in activities of daily living (clinical functional score ≥2) should use the Lake Louise Questionnaire Score to assess the severity of acute mountain sickness.
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Affiliation(s)
- David Meier
- Service of Internal Medicine, Lausanne University Hospital, Lausanne, Switzerland
| | - Tinh-Hai Collet
- Service of Endocrinology, Diabetes, and Metabolism, Lausanne University Hospital, Lausanne, Switzerland
- Ambulatory Care and Community Medicine, University of Lausanne; Lausanne, Switzerland
| | - Isabella Locatelli
- Ambulatory Care and Community Medicine, University of Lausanne; Lausanne, Switzerland
| | - Jacques Cornuz
- Ambulatory Care and Community Medicine, University of Lausanne; Lausanne, Switzerland
| | - Bengt Kayser
- Institute of Sports Sciences, University of Lausanne, Lausanne, Switzerland
| | - David L Simel
- Department of Medicine, Durham VA Medical Center, Durham, North Carolina
- Department of Medicine, Duke University Health System, Durham, North Carolina
| | - Claudio Sartori
- Service of Internal Medicine, Lausanne University Hospital, Lausanne, Switzerland
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23
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Dobrosielski DA, Guadagno M, Phan P. The Association between Regional Fat Distribution and Acute Mountain Sickness in Young Hikers. Sports Med Int Open 2017; 1:E74-E79. [PMID: 30539089 PMCID: PMC6226067 DOI: 10.1055/s-0043-101371] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2016] [Revised: 12/22/2016] [Accepted: 12/24/2016] [Indexed: 12/18/2022] Open
Abstract
Acute mountain sickness (AMS) can occur upon rapid ascent from low to high altitude. This study examined the association between central adiposity and the development of AMS in young adults during a high-altitude hike. Total and regional body fat were measured at sea level using dual-energy X-ray absorptiometry. Within 24 h of arriving in Cusco, Peru (3 400 meters) participants embarked on a 14-mile hike across the Andes Mountain range in southern Peru. Symptoms of AMS were assessed using the Lake Louise score at 24 h (3 400 meters), 29 h (4 100 meters), 34 h (3 800 meters) and 53 h (2 900 meters). 14 participants (mean age 21±2 years; women: 11, men: 3) completed the study. The number of participants exhibiting at least mild AMS increased from 6 (54%) at 3 400 meters to 9 (64%) at 3 800 meters. A higher AMS score at 4 100 meters was associated with greater android (r=0.72, p<0.01), trunk (r=0.73, p<0.01) and total body (r=0.71, p<0.01) fat, but not with total body fat % (r=0.39, p=0.16). Our findings suggest that central obesity, but not total body fat per se, may be an important factor in the development of AMS.
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Affiliation(s)
| | | | - Phillip Phan
- Kinesiology, Towson University, Towson, United States
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Netzer NC, Rausch L, Eliasson AH, Gatterer H, Friess M, Burtscher M, Pramsohler S. SpO 2 and Heart Rate During a Real Hike at Altitude Are Significantly Different than at Its Simulation in Normobaric Hypoxia. Front Physiol 2017; 8:81. [PMID: 28243206 PMCID: PMC5303738 DOI: 10.3389/fphys.2017.00081] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Accepted: 01/27/2017] [Indexed: 11/13/2022] Open
Abstract
Rationale: Exposures to simulated altitude (normobaric hypoxia, NH) are frequently used in preparation for mountaineering activities at real altitude (hypobaric hypoxia, HH). However, physiological responses to exercise in NH and HH may differ. Unfortunately clinically useful information on such differences is largely lacking. This study therefore compared exercise responses between a simulated hike on a treadmill in NH and a similar field hike in HH. Methods: Six subjects (four men) participated in two trials, one in a NH chamber and a second in HH at an altitude of 4,205 m on the mountain Mauna Kea. Subjects hiked in each setting for 7 h including breaks. In NH, hiking was simulated by walking on a treadmill. To achieve maximal similarity between hikes, subjects used the same nutrition, clothes, and gear weight. Measurements of peripheral oxygen saturation (SpO2), heart rate (HR) and barometrical pressure (PB)/inspired oxygen fraction (FiO2) were taken every 15 min. Acute mountain sickness (AMS) symptoms were assessed using the Lake-Louise-Score at altitudes of 2,800, 3,500, and 4,200 m. Results: Mean SpO2 values of 85.8% in NH were significantly higher compared to those of 80.2% in HH (p = 0.027). Mean HR values of 103 bpm in NH were significantly lower than those of 121 bpm in HH (p = 0.029). AMS scores did not differ significantly between the two conditions. Conclusion: Physiological responses to exercise recorded in NH are different from those provoked by HH. These findings are of clinical importance for subjects using simulated altitude to prepare for activity at real altitude. Trial registration: Registration at DRKS. (Approval No. 359/12, Trial No. DRKS00005241).
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Affiliation(s)
- Nikolaus C. Netzer
- Department of Sport Science, University InnsbruckInnsbruck, Austria
- Department for Hypoxia Research, Hermann Buhl Institute for Hypoxia and Sleep Medicine ResearchBad Aibling, Germany
- Division Sports Medicine and Rehabilitation, Department of Medicine, University UlmUlm, Germany
| | - Linda Rausch
- Department for Hypoxia Research, Hermann Buhl Institute for Hypoxia and Sleep Medicine ResearchBad Aibling, Germany
| | - Arn H. Eliasson
- Department of Medicine, Uniformed Services University of the Health SciencesBethesda, MD, USA
| | - Hannes Gatterer
- Department of Sport Science, University InnsbruckInnsbruck, Austria
| | - Matthias Friess
- Department of Sport Science, University InnsbruckInnsbruck, Austria
| | - Martin Burtscher
- Department of Sport Science, University InnsbruckInnsbruck, Austria
| | - Stephan Pramsohler
- Department for Hypoxia Research, Hermann Buhl Institute for Hypoxia and Sleep Medicine ResearchBad Aibling, Germany
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Quantifying the "Slosh Stomach": A Novel Tool for Assessment of Exercise-Associated Gastroparesis Symptoms in Endurance Athletes. JOURNAL OF SPORTS MEDICINE 2016; 2016:1276369. [PMID: 27981229 PMCID: PMC5131242 DOI: 10.1155/2016/1276369] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Revised: 09/27/2016] [Accepted: 10/12/2016] [Indexed: 11/18/2022]
Abstract
Introduction. We describe a novel scale and its field use for evaluation of exercise-associated gastroparesis in the endurance athlete. Methods. A scale was created based on gastroparesis tools previously described in the medical literature. Surveys of the tool were administered to runners participating in a 210 km multiday foot race in Sri Lanka. Results. Use of this novel scale was demonstrated to be useful in assessing gastroparesis severity scores of athletes and how these symptoms affected their race performance. Of the 27 race participants who completed the survey, 27 felt that the tool adequately captured their symptoms. Conclusions. This novel survey tool was able to assess the presence and severity of exercise-associated gastroparesis symptoms in endurance racers in a remote location. This tool may be helpful with further research of the identification and management of gastroparesis and other gastrointestinal upset in the endurance race environment.
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Frühauf A, Burtscher M, Pocecco E, Faulhaber M, Kopp M. Subjective assessment of acute mountain sickness: investigating the relationship between the Lake Louise Self-Report, a visual analogue scale and psychological well-being scales. SPRINGERPLUS 2016; 5:1646. [PMID: 27722064 PMCID: PMC5033803 DOI: 10.1186/s40064-016-3313-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/17/2016] [Accepted: 09/13/2016] [Indexed: 11/12/2022]
Abstract
Purpose There is an ongoing discussion how to assess acute mountain sickness (AMS) in real life conditions. Next to more-item scales with a cut off like the Lake Louise Self-Report (LLS), some authors suggested to use visual analog scales (VAS) to assess AMS. This study tried to contribute to this question using VAS items used for the Subjective Ratings of Drug Effects, including an additional single item for AMS. Furthermore, we investigated if instruments developed to assess psychological well-being might predict AMS assessed via LLS or VAS. Methods 32 (19 Female) adult persons with known AMS susceptibility filled in questionnaires (Feeling Scale, Felt Arousal Scale, Activation Deactivation Check List, LLS, VAS) at a height of 3650 m above sea level. Results Correlation and regression analysis suggest a moderate to high relationship between the LLS score and the VAS items, including one VAS item asking for the severity of AMS, as well as psychological well-being. Conclusion In conclusion, using VAS items to assess AMS can be a more precise alternative to questionnaires like LLS, for people knowledgeable with AMS. Furthermore, researchers should be aware that psychological well-being might be an important parameter influencing the assessment of AMS.
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Affiliation(s)
- Anika Frühauf
- Department of Sport Science, University of Innsbruck, Fürstenweg 185, 6020 Innsbruck, Austria
| | - Martin Burtscher
- Department of Sport Science, University of Innsbruck, Fürstenweg 185, 6020 Innsbruck, Austria
| | - Elena Pocecco
- Department of Sport Science, University of Innsbruck, Fürstenweg 185, 6020 Innsbruck, Austria
| | - Martin Faulhaber
- Department of Sport Science, University of Innsbruck, Fürstenweg 185, 6020 Innsbruck, Austria
| | - Martin Kopp
- Department of Sport Science, University of Innsbruck, Fürstenweg 185, 6020 Innsbruck, Austria
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Koehle MS, Saffer BY, Sinnen NM, MacInnis MJ. Factor Structure and Internal Validity of the Functional Movement Screen in Adults. J Strength Cond Res 2016. [PMID: 26200190 DOI: 10.1519/jsc.0000000000001092] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The factor structure and internal consistency of the Functional Movement Screen (FMS) have not been examined in a general healthcare population. Replicating the factor structure of the FMS is important because it illustrates the interdependence between each of the subtests, enabling the strength and conditioning professional to better interpret and act on an individual's FMS score. Anthropometric data and FMS scores were collected from 1,113 clients of a multidisciplinary healthcare clinic in Vancouver, BC The mean (SD) ages were 53.4 (11.1) for men (n = 656) and 49.3 (12.3) for women (n = 457). The mean FMS Summary Score was 13.7 (2.9) and was significantly negatively correlated with both age (r = -0.25; p < 0.001) and body mass index (r = -0.37; p < 0.001). The internal consistency of the FMS scale, which was assessed with both ordinal and Cronbach's alpha, was 0.73 and 0.64, respectively. Polychoric correlations between individual movements ranged from 0.03 to 0.59. Exploratory and confirmatory factor analyses (CFA) revealed that the FMS showed 2 main factors, a basic movement factor (shoulder mobility and active straight leg raise) and a complex movement factor (squat, hurdle step, inline lunge, and the trunk stability push-up). Rotary stability loaded onto both factors in the CFA, and its exclusion from the model had little effect. The findings of this study broadly replicated the intended factor structure of the FMS, as the individual movements aligned well with the intended factors.
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Affiliation(s)
- Michael S Koehle
- 1Copeman Healthcare Center, Vancouver, Canada; 2School of Kinesiology, University of British Columbia, Vancouver, Canada; 3Division of Sport Medicine, Department of Family Practice, Faculty of Medicine, University of British Columbia, Vancouver, Canada; and 4Department of Psychology, University of British Columbia, Vancouver, Canada
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MacInnis MJ, Koehle MS. Evidence for and Against Genetic Predispositions to Acute and Chronic Altitude Illnesses. High Alt Med Biol 2016; 17:281-293. [PMID: 27500591 DOI: 10.1089/ham.2016.0024] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
MacInnis, Martin J., and Michael S. Koehle. Evidence for and against genetic predispositions to acute and chronic altitude illnesses. High Alt Med Biol. 17:281-293, 2016.-Humans exhibit marked variation in their responses to hypoxia, with susceptibility to acute and chronic altitude illnesses being a prominent and medically important example. Many have hypothesized that genetic differences are the cause of these variable responses to hypoxia; however, until recently, these hypotheses were based primarily on small (and sometimes anecdotal) reports pertaining to apparent differences in altitude illness susceptibility between populations, the notion that a history of altitude illness is indicative of subsequent risk, the heritability of hypoxia-related traits, and candidate gene association studies. In the past 5 years, the use of genomic techniques has helped bolster the claim that susceptibility to some altitude illnesses is likely the result of genetic variation. For each of the major altitude illnesses, we summarize and evaluate the evidence stemming from three important characteristics of a genetic trait: (1) individual susceptibility and repeatability across assessments, (2) biogeographical differences and familial aggregation, and (3) association(s) with genetic variants. Evidence to support a genetic basis for susceptibilities to acute mountain sickness (AMS) and high-altitude cerebral edema (HACE) is limited, owing partially to the subjective and unclear phenotype of AMS and the rarity and severity of HACE. In contrast, recent genomic studies have identified genes that influence susceptibility to high-altitude pulmonary edema, chronic mountain sickness, and high-altitude pulmonary hypertension. The collection of more individual, familial, and biogeographical susceptibility data should improve our understanding of the extent to which genetic variation contributes to altitude illness susceptibility, and genomic and molecular investigations have the potential to elucidate the mechanisms that underpin altitude illness susceptibility.
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Affiliation(s)
| | - Michael S Koehle
- 2 School of Kinesiology, University of British Columbia , Vancouver, Canada .,3 Allan McGavin Sport Medicine Clinic, Department of Family Practice, University of British Columbia , Vancouver, Canada
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MacInnis MJ, Widmer N, Timulsina U, Subedi A, Siwakoti A, Pandit BP, Freeman MG, Carter EA, Manokhina I, Thapa GB, Koehle MS. A Preliminary Genome-Wide Association Study of Acute Mountain Sickness Susceptibility in a Group of Nepalese Pilgrims Ascending to 4380 m. High Alt Med Biol 2015; 16:290-7. [DOI: 10.1089/ham.2015.0065] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Affiliation(s)
- Martin J. MacInnis
- School of Kinesiology, University of British Columbia, Vancouver, British Columbia, Canada
- Department of Kinesiology, McMaster University, Hamilton, Ontario, Canada
| | - Nadia Widmer
- Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Utsav Timulsina
- Maharajgunj Medical Campus, Institute of Medicine, Tribhuvan University, Kathmandu, Nepal
| | - Ankita Subedi
- Maharajgunj Medical Campus, Institute of Medicine, Tribhuvan University, Kathmandu, Nepal
| | - Ashmita Siwakoti
- Maharajgunj Medical Campus, Institute of Medicine, Tribhuvan University, Kathmandu, Nepal
| | - Bidur Prasad Pandit
- Maharajgunj Medical Campus, Institute of Medicine, Tribhuvan University, Kathmandu, Nepal
| | - Michael G. Freeman
- Accident and Emergency Department, Bradford Royal Infirmary, Bradford, United Kingdom
| | - Eric A. Carter
- School of Kinesiology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Irina Manokhina
- Child and Family Research Institute, Vancouver, British Columbia, Canada
- Department of Medical Genetics, Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
| | - Ghan Bahadur Thapa
- Maharajgunj Medical Campus, Institute of Medicine, Tribhuvan University, Kathmandu, Nepal
| | - Michael S. Koehle
- School of Kinesiology, University of British Columbia, Vancouver, British Columbia, Canada
- Faculty of Medicine, University of British Columbia, Vancouver, British Columbia, Canada
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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.
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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
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Abstract
Religious pilgrims have been going to high altitude pilgrimages long before trekkers and climbers sojourned in high altitude regions, but the medical literature about high altitude pilgrimage is sparse. Gosainkunda Lake (4300 m) near Kathmandu, Nepal, and Shri Amarnath Yatra (3800 m) in Sri Nagar, Kashmir, India, are the two sites in the Himalayas from where the majority of published reports of high altitude pilgrimage have originated. Almost all travels to high altitude pilgrimages are characterized by very rapid ascents by large congregations, leading to high rates of acute mountain sickness (AMS). In addition, epidemiological studies of pilgrims from Gosainkunda Lake show that some of the important risk factors for AMS in pilgrims are female sex and older age group. Studies based on the Shri Amarnath Yatra pilgrims show that coronary artery disease, complications of diabetes, and peptic ulcer disease are some of the common, important reasons for admission to hospital during the trip. In this review, the studies that have reported these and other relevant findings will be discussed and appropriate suggestions made to improve pilgrims' safety at high altitude.
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Affiliation(s)
- Buddha Basnyat
- Oxford University Clinical Research Unit-Nepal and Nepal International Clinic , Himalayan Rescue Association, Kathmandu, Nepal
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Bloch KE, Buenzli JC, Latshang TD, Ulrich S. Sleep at high altitude: guesses and facts. J Appl Physiol (1985) 2015; 119:1466-80. [PMID: 26229000 DOI: 10.1152/japplphysiol.00448.2015] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2015] [Accepted: 07/13/2015] [Indexed: 11/22/2022] Open
Abstract
Lowlanders commonly report a poor sleep quality during the first few nights after arriving at high altitude. Polysomnographic studies reveal that reductions in slow wave sleep are the most consistent altitude-induced changes in sleep structure identified by visual scoring. Quantitative spectral analyses of the sleep electroencephalogram have confirmed an altitude-related reduction in the low-frequency power (0.8-4.6 Hz). Although some studies suggest an increase in arousals from sleep at high altitude, this is not a consistent finding. Whether sleep instability at high altitude is triggered by periodic breathing or vice versa is still uncertain. Overnight changes in slow wave-derived encephalographic measures of neuronal synchronization in healthy subjects were less pronounced at moderately high (2,590 m) compared with low altitude (490 m), and this was associated with a decline in sleep-related memory consolidation. Correspondingly, exacerbation of breathing and sleep disturbances experienced by lowlanders with obstructive sleep apnea during a stay at 2,590 m was associated with poor performance in driving simulator tests. These findings suggest that altitude-related alterations in sleep may adversely affect daytime performance. Despite recent advances in our understanding of sleep at altitude, further research is required to better establish the role of gender and age in alterations of sleep at different altitudes, to determine the influence of acclimatization and of altitude-related illness, and to uncover the characteristics of sleep in highlanders that may serve as a study paradigm of sleep in patients exposed to chronic hypoxia due to cardiorespiratory disease.
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Affiliation(s)
- Konrad E Bloch
- Sleep Disorders Center, Pulmonary Division, University Hospital of Zurich, Zurich; Switzerland; Zurich Center for Human Integrative Physiology, University of Zurich, Zurich, Switzerland; and Zurich Center for Interdisciplinary Sleep Research, University of Zurich, Zurich, Switzerland
| | - Jana C Buenzli
- Sleep Disorders Center, Pulmonary Division, University Hospital of Zurich, Zurich; Switzerland
| | - Tsogyal D Latshang
- Sleep Disorders Center, Pulmonary Division, University Hospital of Zurich, Zurich; Switzerland; Zurich Center for Interdisciplinary Sleep Research, University of Zurich, Zurich, Switzerland
| | - Silvia Ulrich
- Sleep Disorders Center, Pulmonary Division, University Hospital of Zurich, Zurich; Switzerland; Zurich Center for Human Integrative Physiology, University of Zurich, Zurich, Switzerland; and
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Smoking Increases the Risk of Acute Mountain Sickness. Wilderness Environ Med 2015; 26:164-72. [DOI: 10.1016/j.wem.2014.10.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Revised: 10/09/2014] [Accepted: 10/13/2014] [Indexed: 11/21/2022]
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Lipman GS, Kanaan NC, Phillips C, Pomeranz D, Cain P, Fontes K, Higbee B, Meyer C, Shaheen M, Wentworth S, Walsh D. Study Looking at End Expiratory Pressure for Altitude Illness Decrease (SLEEP-AID). High Alt Med Biol 2015; 16:154-61. [DOI: 10.1089/ham.2014.1110] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Affiliation(s)
- Grant S. Lipman
- Stanford University School of Medicine, Stanford, California
| | | | | | - Dave Pomeranz
- LA County—USC Emergency Medicine Residency, Los Angeles, California
| | - Patrick Cain
- Midwestern University Emergency Medicine Residency, Chicago, Illinois
| | - Kristin Fontes
- Stanford—Kaiser Emergency Medicine Residency, Palo Alto, California
| | - Becky Higbee
- Stanford—Kaiser Emergency Medicine Residency, Palo Alto, California
| | - Carolyn Meyer
- St. Luke's–Roosevelt Emergency Medicine Residency, New York City, New York
| | - Michael Shaheen
- Stanford—Kaiser Emergency Medicine Residency, Palo Alto, California
| | - Sean Wentworth
- University of Arizona Emergency Medicine Residency, Tucson, Arizona
| | - Diane Walsh
- University of Utah Medical School, Salt Lake City, Utah
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Anderson PJ, Wiste HJ, Ostby SA, Miller AD, Ceridon ML, Johnson BD. Sleep disordered breathing and acute mountain sickness in workers rapidly transported to the South Pole (2835 m). Respir Physiol Neurobiol 2015; 210:38-43. [PMID: 25655218 DOI: 10.1016/j.resp.2015.01.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2014] [Revised: 01/13/2015] [Accepted: 01/21/2015] [Indexed: 11/20/2022]
Abstract
BACKGROUND Sleep disordered breathing may be a risk factor for high altitude illness. Past Antarctic sleep studies suggest that rapid transport from sea level (SL) to the Amundsen Scott South Pole Station (SP, 2835 m) increases risk of Acute Mountain Sickness (AMS). We analyzed sleep studies in 38 healthy polar workers to explore the association between sleep disordered breathing and AMS after rapid transport to the South Pole. METHODS Subjects completed a baseline questionnaire, performed basic physiology tests, and were evaluated for AMS and medication use using an extended Lake Louise Questionnaire (LLQ) during their first week at the South Pole. Participants were included in this study if they took no medications and underwent polysomnography on their first nights at Sea Level and the South Pole using the Vivometrics LifeShirt(®). Within group changes were assessed with Wilcoxon signed rank tests and between group differences were assessed with Kruskal-Wallis rank sum tests. RESULTS Overall, 21/38 subjects met criteria for AMS at some time on or prior to the third morning at the South Pole. Subjective poor sleep quality was reported by both AMS (65%) and no AMS (41%) groups. The Apnea Hypopnea Index (AHI) increased significantly in both the AMS and no AMS groups, but the difference in the increase between the two groups was not statistically significant. Increased AHI was not associated with increased AMS symptoms. Previous altitude illness (p=0.06) and residence at low altitudes (p = 0.02) were risk factors for AMS. CONCLUSION AMS was not significantly associated with sleep architecture changes or increased AHI. However, AHI sharply increased at South Pole (19/38 participants) primarily due to central apneas. Those developing AMS were more likely to have experienced previous problems at altitude and reported living at lowland altitudes within the 3 months prior to rapid transport to the South Pole than those without AMS.
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Affiliation(s)
| | - H J Wiste
- Mayo Clinic, Rochester, MN, United States
| | - S A Ostby
- Mayo Clinic, Rochester, MN, United States
| | - A D Miller
- Mayo Clinic, Rochester, MN, United States
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AbstractsX World Congress on High Altitude Medicine and Physiology & Mountain Emergency MedicineHypoxia and Cold—From Science to TreatmentMay 25–31, 2014Bozen/Bolzano, Italy. High Alt Med Biol 2014. [DOI: 10.1089/ham.2014.1451.abstracts] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
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