BACKGROUND Excessive elevation of arterial blood pressure (BP) at high altitude can be detrimental to our health due to acute mountain sickness (AMS) or some AMS symptoms. This prospective and observational study aimed to elucidate blood pressure changes induced by exposure to high-altitude hypoxia and the relationships of these changes with AMS prevalence, AMS severity, sleep quality and exerc...

UV-B radiation and EOD light (EOD) quality has both signaling and damaging effects based on the dosage and time of exposure. At highland areas UV-B decreases crop productivity and also light quality increase at high elevation area but EOD light quality effect was not researched based on altitude. Therefore, in the present study a field experiment was conducted to investigate the effects of UV-B...

Periodic breathing is often associated with heart disease or stroke, and commonly Cheyne-Stokes breathing has a period of about a minute. Periodic breathing also commonly occurs in healthy subjects at high altitude, and here the periods may be much shorter, of the order of 15-20 s. In this paper we study such periodic breathing using the classical model of Grodins et al. (1967, J. Appl. Physiol...

The lung is the interface between the environment and the metabolic mechanisms of the body, and plays a pivotal role in exposure to high altitude. In fact, high altitude is a challenge for the human body due to the progressive reduction of barometric pressure and subsequent reduction of oxygen pressure, leading to a series of important physiologic responses that enable individuals to tolerate h...

Three tests of small intestinal function were performed at 3100 m and 4846 m to seek evidence of malabsorption of high altitude. Xylose tolerance did not change in 11 subjects but, in three who ascended to 5600 m, one-hour xylose levels were significantly lower. The results of an oxalate loading test did not suggest significant fat malabsorption. A direct fat absorption test using chylomicron l...

More than 140 million people live permanently at high altitude (>2400 m) under hypoxic conditions that challenge basic physiology. Here we present a short historical review of the populating of these regions and of evidence for genetic adaptations and environmental factors (such as exposure to cobalt) that may influence the phenotypic responses. We also review some of the common renal physiolog...

Almost one mountain trekker or climber out of two develops several symptoms of high altitude illness after a rapid ascent (> 300 m/day) to an altitude above 4000 m. Individual susceptibility is the most important determinant for the occurrence of high altitude pulmonary oedema (HAPE). Symptoms associated with HAPE are incapacitating fatigue, chest tightness, dyspnoea at the slightest effort, or...

INTRODUCTION This study aimed to evaluate the retinal changes associated with altitude illness in young soldiers. METHODS A total of 50 young soldiers with altitude illness, who were referred to a tertiary care hospital between October 2003 and January 2006, were included in the study. RESULTS All the soldiers were male. The mean age of the subjects was 30.3 (range 20-44) years. Nine (18 pe...

In high-altitude climbers, the kidneys play a crucial role in acclimatization and in mountain sickness syndromes [acute mountain sickness (AMS), high-altitude cerebral edema, high-altitude pulmonary edema] through their roles in regulating body fluids, electrolyte and acid-base homeostasis. Here, we discuss renal responses to several high-altitude-related stresses, including changes in systemic...