Austrian Moderate Altitude Study (AMAS 2000) – fluid shifts, erythropoiesis, and angiogenesis in patients with metabolic syndrome at moderate altitude (≅1700 m)

Abstract

It was hypothesized that subjects with metabolic syndrome (hypertension, obesity, hyperlipidemia, diabetes mellitus): (1) develop measurable peripheral edema at moderate altitude and (2) might show differences on erythropoiesis, iron status and vascular endothelial growth factor (VEGF) in comparison to healthy subjects during and after a long-term stay (3-week exposure) at moderate altitude (congruent with 1700 m). Twenty-two male subjects with metabolic syndrome were selected. Baseline investigations (t1) were performed in Innsbruck (500 m). All participants were transferred by bus to 1700 m (Alps) and remained there for 3 weeks with examinations on day 1 (after the first night at altitude, t2), day 4 (t3), day 9 (t4) and day 19 (t5). After returning to Innsbruck, post-altitude examinations were conducted after 7-10 days (t6) and 6-7 weeks (t7), respectively. Body mass was decreased from t1 to t7 (P<0.01). Total body water was decreased at t2 (P<0.01), returned to control level (t3, t4), and was found elevated at t7 (P<0.01). Lean body mass did not change, but body fat decreased during the study (P<0.01). Tissue thickness at the forehead decreased during and after altitude exposure (P<0.01), whereas tissue thickness at the tibia did not alter. Erythropoietin (EPO) was elevated as early as t2 and remained increased until t5. Reticulocyte count was increased at t3 and remained above pre-altitude values. VEGF levels were unchanged. After a 3-week exposure to moderate altitude, patients with metabolic syndrome had reduced their body mass, mainly because of a reduction in body fat. The moderate altitude was found to stimulate erythropoiesis in these patients but this was not sufficient to increase serum VEGF concentration.

Transient impairment of flow-mediated vasodilation in patients with metabolic syndrome at moderate altitude (1700 m)

“…The favorable effects of a sojourn at moderate altitude on cardiovascular parameters and on fat and glucose metabolism have already been demonstrated in the pilot project of AMAS-2000 [20,21]. Patients participating in our AMASsubstudy exhibited also improvements in cardiovascular parameters (reduction in resting heart rate, systolic and diastolic blood pressure), and borderline (LDL-C, HDL-C) or significant changes (total cholesterol, triglycerides) in metabolic parameters.…”

“…The main goal of AMAS-2000 was to investigate the effects of a 3-week exercising sojourn at moderate altitude (1700 m) on cardiovascular, metabolic and hematological parameters on tourists with metabolic syndrome. Initial results from the pilot study demonstrated short-term favorable effects on fat and glucose metabolism and a reduction in blood pressure [20,21].…”

AMAS (Austrian Moderate Altitude Study)-2000: Effects of Hiking Holidays at Moderate Altitude on Immune System Markers in Persons with Metabolic Syndrome.

“…Previous publications of data derived from the AMAS study reported favorable effects to a 3-week exposure to 1700 m on body mass, blood pressure, heart rate, Insulin resistance and glucose tolerance (11,12). Among the mediators chosen for the present study to represent an activated immune system in patients with metabolic Syndrome, only neopterin and sTNF-R75 showed a slight but transient increase on days 4 and/or 9 at moderate altitude as compared to baseline levels.…”

The Association of Red Blood Cell Counts with Endothelin-1 in African and Caucasian Women

“…Endothelial dysfunction and increased levels of endothelin-1 are also associated with atherosclerosis, oxidative stress, inflammation, the metabolic syndrome, and malnutrition (12)(13)(14). There are indications that inflammation interact with erythropoiesis, resulting in reduced erythropoietin and red blood cell counts (14,15).…”