Mountaineering And Altitude Sickness: A Study of AMS Prevalence among Climbers of Mount Kinabalu, Malaysia

@#Introduction: Adventure tourism has become one of Malaysia’s most attractive tourism demands, and mountain climbing is rapidly becoming a popular recreational sport. Exploring mountain adventures offers a dynamic experience, preserving this fascinating activity, yet the climbers are exposed to the risk of altitude sickness, such as Acute Mountain Sickness (AMS). This study aimed to evaluate the prevalence of AMS and investigate the effects of high-altitude sickness on the climber profile associated with climbing at Mount Kinabalu, Malaysia. Methods:. The Lake Louise acute mountain sickness LLS score questionnaire collected 95 climber’s data at four different altitudes. SPO2 and Pulse rate was (PR) measured using a finger pulse oximeter. In a cohort study, AMS was measured on day one at 1866m (1st station), 3622m (2nd station), and day two at 3810m (3rd station), and 4095m (4th station). Results: At the altitude of 1866 (Timpohon Gate), the prevalence of AMS was 0%, 30% at 3622m (Laban Rata), 34.7% at 3810m (Sayat-Sayat), and 37.9% at 4095m (Low’s Peak). The overall prevalence of AMS was 37.9% and the majority of AMS cases were moderate in severity and the LLS score is significant with Pulse Rate and peripheral capillary oxygen saturation (SPO2). Conclusion: Concisely, this finding has triggered a need for consideration from multi agencies to enhance mountaineering guidance, especially for beginners or inexperienced hikers, for a suitable package for climbing attempts to reduce the incidence of AMS among Mount Kinabalu climbers.

Expression of Key Enzymes in Glucose Metabolism in Chronic Mountain Sickness and Its Correlation with Phenotype / 中国实验血液学杂志

OBJECTIVE@#To explore the pathogenesis of erythrocytosis by detecting the key enzymes of glucose metabolism and glucose transporter in bone marrow erythrocytes of chronic mountain sickness (CMS), and analyzing its correlation with hemoglobin.@*METHODS@#Twenty CMS patients hospitalized in Qinghai Provincial People's Hospital from January 2019 to December 2020 were selected as CMS group. Twenty males with leukocyte count > 3.5×109/L who had accepted bone marrow aspiration and had normal result were taken as control group. The mRNA and protein expression of key enzymes and glucose transporter in glucose metabolism in bone marrow CD71+ erythrocytes were detected by real time qPCR and Western blot, respectively. Glucose, lactic acid and 2,3-diphosphoglycerate in the bone marrow supernatant and serum were tested by ELISA. The mRNA and protein expression of key enzymes and glucose transporter, glucose, lactic acid and 2,3-diphosphoglycerate of the two groups were compared. Pearson correlation was used to analyze the correlation between key enzymes, glucose transporter in glucose metabolism in bone marrow CD71+ erythrocytes and hemoglobin.@*RESULTS@#The expression of HK2, GLUT1 and GLUT2 mRNA in the CMS group were higher than those in the control group (P<0.001), while the expression of HK1, OGDH and COX5B mRNA were not different. The expression of HK2, GLUT1 and GLUT2 protein in the CMS group were higher than those in the control group (P<0.05). The levels of glucose and lactic acid in the bone marrow supernatant and serum in the CMS group were not different from those in the control group, while the level of 2,3-diphosphoglycerate was higher (P<0.001). Both HK2 and GLUT2 proteins were positively correlated with hemoglobin (r=0.511, 0.717).@*CONCLUSION@#CMS patients may increase glycolysis by increasing the expression of HK2, and promote the utilization of glucose through high expression of GLUT1 and GLUT2 to meet the need of energy supply.

Impact of Moderate Altitude on Lung Diseases and Risk of High Altitude Illnesses

ABSTRACT A large world population resides at moderate altitudes. In the Valley of Mexico (2240 m above sea level) and for patients with respiratory diseases implies more hypoxemia and clinical deterioration, unless supplementary oxygen is prescribed or patients move to sea level. A group of individuals residing at 2500 or more meters above sea level may develop acute or chronic mountain disease but those conditions may develop at moderate altitudes although less frequently and in predisposed individuals. In the valley of México, at 2200 m above sea level, re-entry pulmonary edema has been reported. The frequency of other altitude-related diseases at moderate altitude, described in skiing resorts, remains to be known in visitors to Mexico City and other cities at similar or higher altitudes. Residents of moderate altitudes inhale deeply the city's air with all pollutants and require more often supplementary oxygen.

Application of virtual reality technology in the practice drill training of acute mountain sickness rescue / 中华医学教育探索杂志

Virtual reality (VR) technology is a kind of human-computer interaction technology, which has been widely used in teaching. In the acute mountain sickness rescue teaching practice, we simulated the plateau environment, operation process of prevention and treatment of mountain disease via VR, which were compared with traditional teaching model. Clinical medical undergraduates were selected as the research objects, and the practice effect was compared and analyzed. VR technology makes more rich and diverse teaching methods in acute mountain sickness rescue teaching practice, which has significant advantages in improving the teaching environment and overcoming the shortage of equipment and space. We have optimized the instructional design, realized the teaching mode by combination of virtuality and reality, and improved the teaching quality and test scores.

Un ejemplo de respuesta adaptativa integrada: la aclimatación humana a la altitud / An example of integrated adaptive response: human acclimatization to altitude

Se describen las respuestas fisiológicas que el ser humano desarrolla en respuesta a la exposición a la altitud geográfica. Se describen no sólo las alteraciones debidas a una mala coordinación de los ajustes fisiológicos desencadenados durante la aclimatación a la altura sino también sus manifestaciones clínicas más relevantes. Se detallan los mecanismos moleculares subyacentes a tales respuestas y cómo su mejor conocimiento puede permitir aplicar la exposición intermitente a hipoxia como una herramienta útil para la resolución o alivio de determinadas alteraciones y patologías.

We depict the physiological responses developed by the human body in response to the exposure to geographic altitude. The main alterations due to a noncoordinated setup of the physiological adjustments triggered during the acclimatization at altitude are also described, as its most relevant clinical manifestations. The molecular mechanisms underlying such responses are detailed, and how a better knowledge of these processes can allow us to apply intermittent exposure to hypoxia programs as a useful tool for the resolution or relief of certain disorders and pathologies.

Eritrocitosis excesiva y mal de montaña crónico en mujeres residentes a extrema altura (la Rinconada 5200 msnm, Perú) / Excessive erythrocytosis and acute mountain sickness in women living at extreme altitude (La Rinconada, 5200 msnm, Perú)

El objetivo del trabajo fue determinar la prevalencia y el impacto de la eritrocitosis excesiva (EE) y mal de montaña crónico (MMC) en mujeres, y factores asociados en el desarrollo de estas alteraciones, principalmente la edad e índice de masa corporal (IMC). Los resultados mostraron una prevalencia de EE y MMC, de 19,72% y 25,35%, respectivamente. La edad promedio es de 39,79 ± 10,87; el hematocrito promedio fue 51,95 ± 6,85; la saturación de oxígeno fue 79,88 ± 5,24 y el IMC promedio de la participantes es 28,08 ± 3,87. La prevalencia de EE en el sexo femenino es mayor en las mujeres posmenopáusicas, en comparación a las premenopáusicas. Por otro lado, se determinó que un mayor índice de masa corporal se asocia fuertemente a menores valores de saturación de oxígeno. Entonces, así el incremento de la edad y del índice de masa corporal, favorecen el presencia de eritrocitosis excesiva más marcada condicionando un desarrollo de mal de montaña crónico de mayor severidad.

The aim of the work was to determine the prevalence and impact of excessive erytrochytes (EE) and chronic mountain sickness (MMC) in women, and related factors of the development of these alterations, mainly age and body max index (IMC). Results displayed incidence of EE and MMC, by 19.72% and 25.35%, respectively. The average age was 39.79 ± 10.87; the average hematocrit was 51.95 ± 6.85; the oxygen saturation was 79.88 ± 5.24 and the average IMC of the participants was 28.08 ± 3.87. The prevalence of EE on females is greater in postmenopausal women, in comparison to pre menopausals. On the other hand, it was determined that a greater body mass index is strongly associated to lesser oxygen saturation values. Hence, the increase of age and body max index, favor the most marked excesive erytrochytes presence conditioning the most serious acute mountain sickness.

Función ventricular derecha en residentes nativos a gran altura / Right ventricular function in native residents at high altitude

Los adaptados genéticamente a la altura son los tibetanos, sherpas y etíopes; los aymaras y quechuas están aclimatados (Bolivia, Perú y norte de Chile). En Bolivia el mal crónico de montaña afecta 10% de la población masculina. El objetivo fue determinar la función ventricular derecha en residentes sanos y con mal crónico de montaña mediante ecocardiografía transtoráxica. Se utilizaron participantes sanos y con mal crónico de montaña admitidos por el IBBA, desde el año 2012 al 2013. Las variables tomadas son: demográficas, espirometria forzada, gasometría arterial en reposo e hiperoxia, ECG y ECCTT. Los controles (n 40), la edad promedio (44,13±9,69 años), predominio masculino y sobrepeso (IMC 26,27±6,68kg /m2), procedentes de La Paz 3.600 msnm (54%), Potosí 4.000 msnm (22%), El Alto 4.100 msnm (15%) y Oruro 3.800 msnm (9%), el promedio de Hematocrito 51,34±2,91%, hemoglobina 17,15±0,89gr/ dl, Espirometria forzada y Gasometría arterial en reposo e hiperoxia normales, la ECCTT muestra hipertensión pulmonar leve (35,85±3,64mmHg), aumento de grosor del VD (0,51±0,08), TAPSE (2,94±3,85mmHg) y el índice de Tei (0,44±0,22) normales. Los casos (n 40), la edad promedio (48,43±8,08 años), predominio masculino y sobrepeso (IMC 29,54±3,41kg / m2), procedente de La Paz 3.600 msnm (56%), Potosí 4.000 msnm (24%), El Alto 4.100 msnm (13%) y Oruro 3.800 msnm (7%), Hematocrito 63,08±6,2%, Hemoglobina 21,01±2,01gr/dl con eritrotrocitosis, espirometría forzada normal, gasometría arterial en reposo con hipoxemia moderada (PaO2 51,73±4,68mmHg), hipocapnia (PaCO2 27,62±2,04mmHg) y gradiente Alveolo-arterial aumentado (7,61±3,15). Gasometría arterial en hiperoxia descarta shunt (PaO2 308,9±52,58mmHg), el ECG muestra 2 de 11 criterios de crecimiento VD, la ECCTT con hipertensión pulmonar moderada (PSAP 45,22±5,69mmHg), aumento de grosor del VD (0,73±0,22), TAPSE (2,08±0,18cm), normal e índice de Tei (0,51±0,10) ligeramente aumentado. Se concluyó que la función ventricular derecha se encuentra conservada, a pesar de tener hipertensión pulmonar leve (controles) y moderada (casos), con aumento del grosor del ventrículo derecho.

Those genetically adapted to the height are the Tibetans, Sherpas, and Ethiopians; the Aymara and Quechuas are acclimatized (Bolivia, Peru, and northern Chile). In Bolivia, chronic mountain sickness affects 10% of the male population. The objective was to determine the right ventricular function in healthy residents with chronic mountain sickness using transthoracic echocardiography. Use the healthy and chronically ill mountain participants admitted by the IBBA, from 2012 to 2013. The variables taken are demographic, forced spirometry, arterial blood gas at rest and hyperoxia, ECG, and ECCTT. Controls (n 40), average age (44.13 ± 9.69 years), male predominance and overweight (BMI 26.27 ± 6.68kg / m2), frequency from La Paz 3,600 masl (54%), Potosí 4,000 masl (22%), El Alto 4,100 masl (15%) and Oruro 3,800 masl (9%), the average Hematocrit 51.34 ± 2.91%, hemoglobin 17.15 ± 0.89gr / dl, Forced spirometry y Resting arterial blood gas and normal hyperoxia, ECCTT shows mild pulmonary hypertension (35.85 ± 3.64 mmHg), increased RV thickness (0.51 ± 0.08), TAPSE (2.94 ± 3.85 mmHg ) and the Tei index (0.44 ± 0.22) normal. The cases (n 40), the average age (48.43 ± 8.08 years), male predominance and overweight (BMI 29.54 ± 3.41kg / m2), derived from La Paz 3,600 masl (56%), Potosí 4,000 masl (24%), El Alto 4,100 masl (13%) and Oruro 3,800 masl (7%), Hematocrit 63.08 ± 6.2%, Hemoglobin 21.01 ± 2.01gr / dl with erythrocytosis, normal forced spirometry , resting arterial blood gas with moderate hypoxemia (PaO2 51.73 ± 4.68mmHg), hypocapnia (PaCO2 27.62 ± 2.04mmHg) and increased Alveolo-arterial gradient (7.61 ± 3.15). Arterial blood gas in hyperoxia rules out shunt (PaO2 308.9 ± 52.58mmHg), ECG shows 2 of 11 RV growth criteria, ECCTT with moderate pulmonary hypertension (PSAP 45.22 ± 5.69mmHg), increased RV thickness (0.73 ± 0.22), TAPSE (2.08 ± 0.18cm), normal and Tei index (0.51 ± 0.10) slightly increased. It was concluded that the right ventricular function is preserved, a weight of having mild pulmonary hypertension (controls) and moderate (cases), with increased thickness of the right ventricle.

Mal agudo de montaña: pasado, presente y futuro / Acute mountain sickness: past, present and future

Evidencias en textos históricos Chinos de los años 403 AC y de la Conquista Española en 1590, muestran de las condiciones singulares que afectaban tanto a hombres como a animales al ascender por sectores montañosos por sobre 4000 m., y que ahora reconocemos como mal agudo de montaña. Ya desde el siglo XIX, se ha reconocido que es la falta de oxígeno (hipoxia) el factor determinante de la respuesta aclimatatoria como de la desaclimatización a la hipoxia de altura. El objetivo de la actual revisión fue una puesta al día de definiciones, factores que inciden en una mayor incidencia de mal agudo de montaña, mecanismo fisiológico propuesto, el desarrollo de estrategias farmacológicas para la prevención y/o tratamiento y por último, se ha revisado respecto de las distintas estrategias que se han desarrollado para la evaluación de la susceptibilidad individual, conocido comúnmente como test de hipoxia.

Some Chinese historical text from 403 BC and the Spanish Conquest in 1590 indicates unique conditions that affected both men and animals when climbing mountainous areas over 4000 m. and that is currently known as Acute Mountain Sickness (MAM). Since the XIX century, the lack of oxygen (hypoxia), has been recognized as the main factor of the acclimatization and declimatization to the high altitude hypoxia. The aim of the current revision is an update of definitions, factors that contribute the Acute Mountain Sickness, the proposed physiological mechanism, the development of pharmacological strategies for the prevention and/or treatment, and finally, we reviewed the different strategies developed for the individual susceptibility assessment, generally known as hypoxia test.

Ibuprofeno comparado con acetazolamida para prevención de mal agudo de montaña / Ibuprofen versus acetazolamide for prevention of acute mountain sickness

INTRODUCCIÓN: El mal agudo de montaña es una condición frecuente en individuos sanos, sin aclimatación que se exponen a alturas desde 2500 metros sobre el nivel del mar. Clásicamente se ha utilizado acetazolamida para prevenirlo, pero en los últimos años ha surgido evidencia a favor de ibuprofeno. Sin embargo, no está claro cuál de estos tratamientos es más efectivo. MÉTODOS: Realizamos una búsqueda en Epistemonikos, la mayor base de datos de revisiones sistemáticas en salud, la cual es mantenida mediante el cribado de múltiples fuentes de información, incluyendo MEDLINE, EMBASE, Cochrane, entre otras. Extrajimos los datos desde las revisiones identificadas, analizamos los datos de los estudios primarios, realizamos un metanálisis y preparamos una tabla de resumen de los resultados utilizando el método GRADE. RESULTADOS Y CONCLUSIONES: Identificamos dos revisiones sistemáticas que en conjunto incluyeron un estudio primario, el cual corresponde a un ensayo aleatorizado. Concluimos que no es posible establecer con claridad si ibuprofeno es mejor o peor que acetazolamida debido a que la certeza de evidencia existente ha sido evaluada como muy baja.

INTRODUCTION: Acute mountain sickness is a common condition occurring in healthy subjects that undergo rapid ascent without prior acclimatization, as low as 2500 meters above sea level. The classic preventive agent has been acetazolamide, although in the last decade there has been evidence favoring ibuprofen. However, it is unclear which method is more efficient. METHODS: We searched in Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, Cochrane, among others. We extracted data from the systematic reviews, reanalyzed data of primary studies, conducted a meta-analysis) and generated a summary of findings table using the GRADE approach. RESULTS AND CONCLUSIONS: We identified two systematic reviews that included only one primary study, which is a randomized trial. We concluded it is not possible to establish whether ibuprofen is better or worse than acetazolamide because the certainty of evidence has been evaluated as very low.

Phytochemistry and Biological Activities of Werneria and Xenophyllum species / Fitoquímica y actividades biológicas de especies de Werneria y Xenophyllum

Plants of the genera Werneria (Asteraceae) and Xenophyllum (genus extracted from Werneria) are used in traditional medicine of Latin America for the treatment of mountain sickness, hypertension and gastrointestinal disorders. Only a small number of species of these genera have been studied, leading to the isolation of compounds belonging to the classes of benzofurans, chromenes, acetophenones, coumarates, diterpenes and pyrrolizidine alkaloids. Some of the plant extracts and/or compounds have shown antimicrobial, anti-HIV, hypotensive and photoprotective activities.

Las plantas de los géneros Werneria (Asteraceae) y Xenophyllum (género extraido de Werneria) son usadas en la medicina tradicional de América Latina para el tratamiento del mal de montaña, hipertensión y desórdenes gastrointestinales. Solo un pequeño número de especies de estos géneros ha sido investigado, lográndose aislar compuestos que pertenecen a las clases de benzofuranos, cromenos, acetofenonas, cumaratos, diterpenos y alcaloides pirrolizidínicos. Algunos de los extractos y/o compuestos de dichas plantas han mostrado actividades antimicrobianas, anti-HIV, hipotensoras y fotoprotectoras.

Analysis of the acute mountain sickness risk factor behind chinese young men’s acute exposure to high altitude: A field cohort study on plateau / 解放军医学杂志

[Abstract] Objective To investigate the risk factors and predictive factors for acute mountain sickness (AMS) after acute exposure to high altitude. Methods Eighty-three subjects were airlifted from Chengdu (elevation 500m) to Lhasa (elevation 3700m) in 2 hours, and divided into AMS(+) group and AMS(–) group according to the LLS AMS scores (2018). Subjects were tested both in plain (Chengdu) and plateau (Lhasa). With the case report form (CRF), the demographic data, AMS related symptoms, self-rating anxiety scale (SAS) and fatigue self-assessment scale (FSAS) were collected, meanwhile the heart rate, blood pressure and percutaneous oxygen saturation (SpO2) were detected. The cardiac ultrasound was performed, and the subjects' venous blood was collected to detect vasoconstriction and vasodilatation factors with ELISA. Logistic regression analysis was performed to screen the independent risk factors for AMS. Results As 4 subjects were lost, a total of 79 subjects were eventually included in present study. After acutely exposed to high altitude, the subjects' SAS, FSAS and HR aroused obviously (P<0.05), while the SpO2 decreased markedly (P<0.05). There was also a significant increase in systemic and cerebral hemodynamics (P<0.05). Plasma levels of endothelin-1 and bradykinin increased (P<0.05), while of nitric oxide, prostaglandin E and serotonin decreased (P<0.05). Furthermore, when the subjects were located in plain area, the left ventricular end-diastolic diameter (LVEDD) was obviously higher in AMS(+) group [(47.11±2.90)mm] than in AMS(–) group [(45.51±2.17)mm, P=0.008], while after acutely exposed to high altitude, the SAS and FSAS were markedly higher in AMS(+) group than in AMS(–) group (P=0.001), and the systolic blood flow velocity of basilar artery was also higher in AMS(+) group [(70.30±15.71)cm/s] than in AMS(–) group [(63.06±11.81)cm/s, P=0.026]. With regression analysis, it is shown that LVEDD could independently indicate the occurrence of AMS in the plain area (OR=1.293, 95%CI 1.058-1.581, P=0.012), and the systolic blood flow of basilar artery (OR=1.055, 95%CI 1.005-1.107, P=0.030), right atrium diameter (RAD, OR=0.731, 95%CI 0.543-0.984, P=0.039), SAS (OR=1.219, 95%CI 1.027-1.447, P=0.023) and FSAS (OR=1.105, 95%CI 1.016-1.201, P=0.019) were closely correlated with AMS after acutely exposed to high-altitude (P<0.05). Conclusions The baseline LVEDD has predictive value for AMS in plain area. After exposure to high altitude, the posterior cerebral circulation hemodynamics, anxiety and fatigue may trigger the occurrence of AMS.

Brain injury and drug therapy in high-altitude environment: research advances / 国际药学研究杂志

Altitude sickness is a common disease caused by hypotension and hypoxia due to low pressure when people move from the plain to the plateau, which causes injury to the respiratory system, cardiovascular system, and ner- vous system. The brain tissue is very sensitive to the decrease in oxygen partial pressure, which can easily cause neuro- nal dysfunction and even lead to neuron apoptosis. The partial pressure of oxygen in the plateau environment is low, and an effective way to improve the host defense ability is to develop anti-hypoxia drugs that improve the ratio of oxyen utiliza- tion. This paper reviews and summarizes the clinical symptoms of the nervous system in the high-altitude environment, including high-altitude headache, acute mountain sickness and high-altitude cerebral edema, as well as the pathophysio- logical molecular mechanisms and related drug treatments, so as to develop the effective new drugs of anti-hypoxia brain damage and to guide the rational use of clinical scientific drugs.

Acetazolamida como tratamiento del mal agudo de montaña / Acetazolamide for the treatment of acute mountain sickness

INTRODUCCIÓN El mal agudo de montaña es la patología más prevalente relacionada con la exposición aguda a la altura, secundaria a los efectos de la hipoxia hipobárica en nuestro organismo. La acetazolamida se ha utilizado tradicionalmente para su prevención y tratamiento, sin embargo, aún existe controversia respecto al grado de utilidad que tiene este medicamento como monoterapia. MÉTODOS Realizamos una búsqueda en Epistemonikos, la mayor base de datos de revisiones sistemáticas en salud, la cual es mantenida mediante el cribado de múltiples fuentes de información, incluyendo MEDLINE, EMBASE, Cochrane, entre otras. Extrajimos los datos desde las revisiones identificadas, analizamos los datos de los estudios primarios, realizamos un meta análisis y preparamos una tabla de resumen de los resultados utilizando el método GRADE. RESULTADOS Y CONCLUSIONES Identificamos una revisión sistemática que incluyó dos estudios primarios, ambos correspondientes a ensayos aleatorizados. Concluimos que no es posible establecer con claridad si el tratamiento con acetazolamida disminuye los síntomas del mal agudo de montaña ni si aumenta el riesgo de efectos adversos, debido a que la certeza de la evidencia existente ha sido evaluada como muy baja.

INTRODUCTION Acute mountain sickness is the most prevalent illness related to acute exposure to high altitude, secondary to the hypobaric hypoxia effects in our body. Acetazolamide has been traditionally used for its prevention and treatment, however, there is still controversy regarding the degree of usefulness of this medication as monotherapy. METHODS We searched in Epistemonikos, the largest database of systematic reviews in health, which is maintained by screening multiple information sources, including MEDLINE, EMBASE, Cochrane, among others. We extracted data from the systematic reviews, reanalyzed data of primary studies, conducted a meta-analysis and generated a summary of findings table using the GRADE approach. RESULTS AND CONCLUSIONS We identified a systematic review that included two primary studies, both corresponding to randomized trials. We conclude that it is not possible to establish clearly whether treatment with acetazolamide reduces the symptoms of acute mountain disease or increases the risk of adverse effects, because the certainty of the existing evidence has been evaluated as very low.

Occurrence of high altitude cerebral edema (hace) and high altitude pulmonary edema (HAPO) simultaneously at 12000 ft: a rare phenomen

High altitude cerebral edema (HACE) and High altitude pulmonary edema (HAPO) are the most dreaded complications related to high altitude. Authors managed a case of HACE and HAPO simultaneously set at unusually low height (1200 ft) in a patient. The altitude was not too much to develop these comorbidities as studied earlier. Relationship with altitude was immaterial in our case. However, rapid ascent without proper acclimatisation, young and tender age, male sex and smoking were associated contributing factors. He was managed with standard protocol and descent to lower altitude.

Prevalence and risk factors of chronic mountain sickness in Pamirs plateau / 中国应用生理学杂志

OBJECTIVE@#To investigate the prevalence of chronic mountain sickness (CMS) and its predisposing factors in Pamirs plateau and analysis clinical feature and risk factors.@*METHODS@#Eight hundred and twenty-four individuals in Pamirs plateau were surveyed used Qinghai CMS scoring system. Demographics, BP, SaO, heart rate and specified symptoms of CMS were recorded, Hb level was estimated.@*RESULTS@#Overall CMS prevalence was 22.08%, including 21.84% mild and 0.24% moderate without severe patient. Gender, nation, age, immigration time, altitude, occupation and accommodation mode were risk factors for CMS (<0.05 or <0.01), CMS prevalence was higher than HAPC rate both in male and female (χ=90.59 and 44.13, <0.01). Multiple linear regression analysis showed age, BMI, SaO and systolic pressure correlated with CMS (<0.01).@*CONCLUSIONS@#Chronic mountain sickness prevalence in Pamirs plateau is rather high but high altitude polycythemia prevalence is low, so the disease type is high altitude deterioration. Work and exercise more reasonable to avoid overtiredness, oxygen inhalation to raise blood oxygen saturation, control blood pressure and resting therapy can improve CMS symptom and decrease prevalence.

The value of diffusion kurtosis imaging combined with diffusion weighted imaging in evaluating the microstructure of cerebral gray and white matter in chronic mountain sickness / 实用放射学杂志

Objective To explore the gray and white matter microstructures in the brain of patients with different degrees of chronic mountain sickness(CMS).Methods 30 cases of CMS (10 cases in each group divided into mild,moderate and severe groups according to the severity)were collected as experimental group,and 10 normal adults in high altitude area were collected as the normal control group.All cases underwent MRI conventional head sequences,diffusion weighted imaging (DWI)and diffusion kurtosis imaging (DKI)sequences.The values of mean kurtosis(MK),radial kurtosis(RK),kurtosis anisotropy(KA)and apparent diffusion coefficient(ADC) graphs were reconstructed by post-processing software respectively.Selected the region of interest(ROI)symmetrically and fixedly, then measured and analyzed the parameter values of ROI in the same area.Results Compared the CMS groups with normal control group,the diffusion parameters and ADC values in certain parts of deep gray matter nucleus and white matter fibers were statistically significant,and the difference was significant with the progression of the disease.Conclusion DKI combined with DWI has certain value in evaluating the gray and white matter microstructure of human brain,there are some difference in the brain microstructure between CMS patients and high altitude normal subjects,additionally,the difference in different degrees of CMS is diverse.

Study on myocardium and brain damage in rats by simulating high altitude / 药学实践杂志

Objective To investigate the effect of hypoxia with cold on the heart and brain damage in rats by simulating 6 000 m high altitude at different exposure time,established a rat model of acute mountain sickness for the related mechanism studies.Methods 32 healthy male Wistar rats were randomly divided into normal control group,hypoxia with cold 1 d,3 d and 5 d group,8 rats in each group.The normal control group was kept in the plain environment(1 500 m)without any treat-ment.The other three groups were placed in large hypobaric hypoxia chamber to simulate 6 000 m altitude with different ex-posed times.HE staining was used to observe the pathological changes of heart and brain tissue.The changes of biochemical indexes were measured to evaluate the damage of heart and brain tissue at different hypoxia times.Results HE staining showed that hypoxia with cold induced rat heart and brain damage with different degrees.The myocardial tissue damage was in-creased with exposure time.The most serious brain damage happened in day 3.Compared with the normal control group,the content of MDA and LD in the myocardial tissue of hypoxia rats were significantly increased(P<0.05 or P<0.01)with pro-longed time,while the contents of GSH,T-SOD and the activity of Na+K+-ATPase were reduced(P<0.05 or P<0.01). The content of MDA in brain tissue was significantly increased at day 1 and day 3(P<0.05 or P<0.01).LD content was sig-nificantly increased(P<0.05)with time.The content of GSH,the activity of T-SOD and Na+K+-ATPase were significantly reduced in day 3(P<0.05).Conclusion Simulating an altitude of 6 000 m caused obvious damage on the heart and brain tis-sues of rats.The degree of damage was related to the exposure time to hypoxia with cold.The decrease of body′s antioxidant capacity,the increase of free radicals and energy metabolism disorders are important factors leading to heart and brain injury.

Changes of hemodynamic and cerebral oxygenation after exercise in normobaric and hypobaric hypoxia: associations with acute mountain sickness

OBJECTIVE: Normobaric (NH) and hypobaric hypoxia (HH) are associated with acute mountain sickness (AMS) and cognitive dysfunction. Only few variables, like heart-rate-variability, are correlated with AMS. However, prediction of AMS remains difficult. We therefore designed an expedition-study with healthy volunteers in NH/HH to investigate additional non-invasive hemodynamic variables associated with AMS. METHODS: Eleven healthy subjects were examined in NH (FiO2 13.1%; equivalent of 3.883 m a.s.l; duration 4 h) and HH (3.883 m a.s.l.; duration 24 h) before and after an exercise of 120 min. Changes in parameters of electrical cardiometry (cardiac index (CI), left-ventricular ejection time (LVET), stroke volume (SV), index of contractility (ICON)), near-infrared spectroscopy (cerebral oxygenation, rScO2), Lake-Louise-Score (LLS) and cognitive function tests were assessed. One-Way-ANOVA, Wilcoxon matched-pairs test, Spearman’s-correlation-analysis and Student’s t-test were performed. RESULTS: HH increased heart rate (HR), mean arterial pressure (MAP) and CI and decreased LVET, SV and ICON, whereas NH increased HR and decreased LVET. In both NH and HH cerebral oxygenation decreased and LLS increased significantly. After 24 h in HH, 6 of 11 subjects (54.6%) developed AMS. LLS remained increased until 24 h in HH, whereas cognitive function remained unaltered. In HH, HR and LLS were inversely correlated (r = − 0.692; p < 0.05). More importantly, the rScO2-decrease after exercise in NH significantly correlated with LLS after 24 h in HH (r = − 0.971; p < 0.01) and rScO2 correlated significantly with HR (r = 0.802; p < 0.01), CI (r = 0.682; p < 0.05) and SV (r = 0.709; p < 0.05) after exercise in HH. CONCLUSIONS: Both acute NH and HH altered hemodynamic and cerebral oxygenation and induced AMS. Subjects, who adapted their CI had higher rScO2 and lower LLS. Furthermore, rScO2 after exercise under normobaric conditions was associated with AMS at high altitudes.

Analysis of hospitalized cases with atrial fibrillation in high altitude areas in Tibet / 中国介入心脏病学杂志

Objective To analyze the etiological or associated factors and the treatment of patients with atrial fi brillation in high altitude areas in Tibet. Methods The clinical data of atrial fi brillation patients hospitalized in our hospital during January 2012 to Jane 2016 were analyzed retrospectively. Results (1) A total of 442 patients (male:female,1.2:1) were included in the study with ages of 30-96(65.9±12.3) years. The percentages of paroxysmal, persistent and permanent atrial fi brillation were 14.9%, 69.2%, and 15.8% respectively. The associated factors of atrial fi brillation included hypertension (53.4%), rheumatic heart disease (7.5%),chronic mountain sickness (10.6%), coronary heart disease(5.7%), hyperthyroidism (6.1%) and diabetes (9.0%).(2)Only 42 patients (9.5%) had evaluation with CHADS2score during hospitalization and actually 74.6% patients scored≥2. Twenty-one patients were restored to sinus rhythm during hospitalization and no patients had radiofrequency ablation.Conclusions The associated factors of atrial fi brillation in high altitude areas are similar to other areas. Thrombosis risk evaluation and anticoagulation therapy was not sufficient. Rhythm control rate was low and development of radio frequency ablation therapy should be considered.

Meta Analysis of the Relationship between Overweight, Obesity and Acute Mountain Sickness / 医学研究杂志

Objective To investigate the relationship between overweight,obesity and acute mountain sickness(AMS).Methods We searched the WanFang,CNKI,VIP,PubMed,Embase,Springer,Google Scholar,Cochrane databases.AMS,acute high altitude disease,acute high altitude disease (AHAD),hypoxic ventilatory response (HVR),obese,obesity,BMI,Body Mass Index,cohort study,case-control study,cross-sectional study and observational study were used to search literatures which studied association between overweight,obesity and AMS during 2007-2016.Literatures were then evaluated by two evaluators.RevMan 5.3 software was utilized for statistical analysis.Results Six articles with 6323 cases were included in the study.The heterogeneity test result revealed that included studies were statistically heterogeneous (I2 =93％,P ＜ 0.01),therefore,the random effect model was used to analyze.Obesity and overweight significantly increased the occurrence of AMS with an OR of 2.39 (95％ CI:1.21-4.70).Egger's test indicated that there was no publication bias (P ＞ 0.05).Conclusion Overweight and obesity can be used as predictors of occurrence for AMS.