[Acute mountain sickness at 3500 and 4250 m. A study of symptom, incidence and severity].
BACKGROUND
Acute Mountain Sickness (AMS) refers to signs and symptoms associated with hypobaric hypoxia. Its reported incidence is highly variable.


OBJECTIVE
To determine the incidence of AMS symptoms and severity at 3,500 and 4,250 m above sea level.


METHODS
A population of 362 soldiers without former exposure to altitude was studied. AMS symptoms, were assessed by an extensively used standard questionnaire (Lake Louise), applied 36-72 hours after exposure to high altitude.


RESULTS
A group of 200 recruits ascended to Putre (3,500 m) and a second group (162) ascended to Alto Pacollo (4,250 m). The incidence of AMS was 28% and 60% respectively (p < 0.05). Headaches and sleeping difficulties were the most frequent symptoms at both altitudes. Furthermore, severe digestive problems and dizziness were described in a high proportion of individuals at both 3,500 and 4,250 m.


CONCLUSIONS
The prevalence of AMS in this study is similar to that reported elsewhere at equivalent altitudes.
Vargas
M
M
Centro de Investigación en Medicina de Altura (CIMA), Mutual de Seguridad, C.CH.C., Iquique, Chile. medaltur@entelchile.net
Osorio
J
J
Jiménez
D
D
Moraga
F
F
Sepúlveda
M
M
Del Solar
J
J
Hudson
C
C
Cortés
G
G
León
A
A
D000208:Acute Disease; D000293:Adolescent; D000532:Altitude Sickness / Q000150:complications* / Q000453:epidemiology; D002677:Chile / Q000453:epidemiology; D006801:Humans; D015994:Incidence; D008889:Military Personnel; D012720:Severity of Illness Index