LAUSR

BACKGROUND Acute mountain sickness (AMS) may occur after rapid ascents to altitudes > 2500 m. Cusco (3350 m) in Peru is a popular destination for altitude inexperienced travelers. This study aimed at evaluating the incidence and risk factors for AMS among a cohort of foreign Spanish language students in Cusco. METHODS We performed a cohort study among young healthy foreign Spanish language students arriving to Cusco between 2012 and 2016. Consenting students answered an enrollment questionnaire on demographics, travel history, and intended AMS preventive behavior within 48 hours of arrival. At 4 to 5 days after enrollment participants answered a second questionnaire about actual preventive behavior before symptoms and the development of symptoms compatible with AMS during their first 48 hours in Cusco. We used the 2018 Lake Louis Scoring System (LLSS) for AMS diagnosis. Participants with headache and a score ≥ 3 were considered to have AMS. RESULTS We enrolled 142 language students, the median age was 21 years (IQR 20-25) and 57% were female. Participants decreased physical activity (38%), increased fluid intake (34%), drank coca leaf tea (34%), took acetazolamide (16%), and acclimatized at a lower altitude (6%) to prevent AMS. Thirty nine percent had AMS. In the multivariate analysis, obesity (OR 14.45 [2.33-89.6]) and female sex (OR 4.32 [1.81-10.28]) were associated with increased risk of AMS. Taking acetazolamide (OR 0.13 [0.03-0.56) was associated with decreased AMS risk. Consumption of coca leaf tea was not associated with decreased risk of AMS. CONCLUSIONS In our cohort, AMS affected two out of five travelers. Obesity and female sex were associated with increased risk. Drinking coca leaf tea for prevention did not decrease the risk of AMS. Acetazolamide prophylaxis was associated with decreased risk of AMS.