Iron deficiency is a possible risk factor causing right heart failure in Tibetan children living in high altitude area

Physical fitness of Tibetan adolescents at different high altitudes in Tibet, China: A comparative study

OBJECTIVE

High altitude hypoxic environment has a certain negative impact on physical fitness of adolescents. We aimed to understand the physical fitness status of Tibetan adolescents in different high-altitude areas in Tibet, China.

METHODS

Physical fitness items, such as grip strength, standing long jump, sit and reach, 50 m dash, 1000 m run for boys, and 800 m run for girls were tested on 3806 Tibetan adolescents by using stratified whole group sampling method in class units. The mean age of the participants was (15.51 ± 1.69) years for Tibetan males and (15.54 ± 1.69) years for females. One-way analysis of variance (ANOVA) and other methods were used to make cross-sectional comparisons of physical fitness performance of Chinese Tibetan adolescents in different high-altitude regions.

RESULTS

The standing long jump scores of boys (203.37 ± 28.36) were higher than that of girls (152.97 ± 19.46) and the lowest standing long jump scores of adolescents in Shigatse region (166.39 ± 35.04). The highest level of sit and reach was found among boys (10.69 ± 5.34) in Nyingchi and the lowest level of sit and reach was found among girls (8.42 ± 5.84) in Shigatse. Shigatse region adolescents had the lowest performance in 50 m dash (9.09 ± 1.72) while the best performance in 1000 m run (266.23 ± 35.82) and 800 m run (245.40 ± 27.92).

CONCLUSION

There is variability in the physical fitness of Tibetan adolescents in different high-altitude regions of Tibet, China. Targeted physical fitness interventions should be carried out for Tibetan adolescents in different high-altitude regions. The focus should be on improving the endurance quality of Tibetan adolescents in Lhasa and the lower limb muscle strength, flexibility, and speed quality of adolescents in Shigatse.

Pulmonary Hypertension in Acute and Chronic High Altitude Maladaptation Disorders

Alveolar hypoxia is the most prominent feature of high altitude environment with well-known consequences for the cardio-pulmonary system, including development of pulmonary hypertension. Pulmonary hypertension due to an exaggerated hypoxic pulmonary vasoconstriction contributes to high altitude pulmonary edema (HAPE), a life-threatening disorder, occurring at high altitudes in non-acclimatized healthy individuals. Despite a strong physiologic rationale for using vasodilators for prevention and treatment of HAPE, no systematic studies of their efficacy have been conducted to date. Calcium-channel blockers are currently recommended for drug prophylaxis in high-risk individuals with a clear history of recurrent HAPE based on the extensive clinical experience with nifedipine in HAPE prevention in susceptible individuals. Chronic exposure to hypoxia induces pulmonary vascular remodeling and development of pulmonary hypertension, which places an increased pressure load on the right ventricle leading to right heart failure. Further, pulmonary hypertension along with excessive erythrocytosis may complicate chronic mountain sickness, another high altitude maladaptation disorder. Importantly, other causes than hypoxia may potentially underlie and/or contribute to pulmonary hypertension at high altitude, such as chronic heart and lung diseases, thrombotic or embolic diseases. Extensive clinical experience with drugs in patients with pulmonary arterial hypertension suggests their potential for treatment of high altitude pulmonary hypertension. Small studies have demonstrated their efficacy in reducing pulmonary artery pressure in high altitude residents. However, no drugs have been approved to date for the therapy of chronic high altitude pulmonary hypertension. This work provides a literature review on the role of pulmonary hypertension in the pathogenesis of acute and chronic high altitude maladaptation disorders and summarizes current knowledge regarding potential treatment options.