Chia-Hua, K., Wen-Chih, L., & Ivy, J. L. (2007). The magnitude of physiological response to altitude is associated with individual variation in DHEA-S levels. ACSM Annual Meeting New Orleans, Presentation Number, 925.

"Dehydroepiandrosterone-sulfate (DHEA-S) has been previously documented to have a buffering action against stress and was found to reduce under major stress conditions, we speculated that DHEA-S may be essential in coping with mountaineering stress and required for altitude acclimatization". This study investigated the effect of a 25-day mountaineering activity on glucose tolerance and its relation to serum levels of DHEA-S and tumor necrosis factor-alpha (TNF-alpha) in males (N = 12). Glucose tolerance, insulin level, TNF-alpha, and the normal physiologic responses to altitude exposure including hematocrit, hemoglobin, erythropoietin, and cortisol were measured at sea-level and at altitude.

On Day 3 at altitude, serum DHEA-S dropped in Ss with initially greater DHEA-S values, whereas Ss with initially lower DHEA-S values remained unchanged. All Ss were then divided into lower and upper halves according to their sea-level DHEA-S concentrations: Glucose and insulin concentrations on an oral glucose tolerance test were significantly lowered by the mountaineering activity only in the High DHEA-S group. Similarly, haematocrit and haemoglobin concentration in altitude increased only in the High DHEA-S group. In contrast, the Low DHEA-S Ss exhibited greater erythropoietin values at sea-level and altitude above the High DHEA-S group, suggesting an erythropoietin resistance.

Implication. DHEA-S is essential for physiological acclimatization to a mountaineering challenge. The nature and extent of the response depends upon the initial level of DHEA-S in the individual.

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