Study objectives: To investigate the hypothesis that an increase in circula
ting vascular endothelial growth factor (VEG-F) occurs in mountaineers at h
igh altitude, particularly in association with acute mountain sickness (AMS
) and/or low hemoglobin oxygen saturation.
Design: Collection of medical histories, AMS scores, plasma samples, and ar
terial oxygen saturation (Sao,) measurements from mountaineers at 1,500 fee
t (sea level) and at 14,200 feet.
Setting: Mount McKinley ("Denali"), AK.
Participants: Sixty-six: mountaineers.
Interventions: None.
Measurements and results: Plasma VEGF at 14,200 feet was not increased in a
ny group, In fact, plasma VEGF was significantly lower in subjects who did
not develop AMS (53 +/- 7.9 pg/mL; mean +/- SEM; n = 47) compared to contro
l subjects at sea level (98.4 +/- 14.3 pg/mL; n = 7; p = 0.005), Plasma VEG
F at 14,200 feet for subjects with AMS (62 +/- 12 pg/mL; n = 15) did not di
ffer significantly from subjects at 14,200 feet without AMS, or from contro
l subjects at sea level. Of a small number of subjects with paired specimen
s at sea level and at base camp (n = 5), subjects who exhibited a decrease
in plasma VEGF at 14,200 feet were those who did not develop AMS. Neither S
ao(2), prior AMS, AMS symptom scores, or acetazolamide use were correlated
with plasma VEGF,
Conclusions: Subjects at high altitude who do not develop AMS have lower pl
asma VEGF levels compared to control subjects at sea level. Plasma VEGF at
high altitude is not elevated in association with AMS or hypoxia, Sustained
plasma VEGF at altitude may reflect a phenotype more susceptible to AMS.