Predictive Capacity of Pulmonary Function Tests for Acute Mountain Sickness.

Area of Science:

• Altitude Medicine and Physiology
• Respiratory Medicine
• Sports Medicine

Background:

• Pulmonary function tests (PFTs), including spirometry, have yielded inconsistent results when studied at high altitudes.
• Existing research on the relationship between spirometry and acute mountain sickness (AMS) is limited.
• Understanding predictors for AMS is crucial for preventing and managing altitude-related illnesses.

Purpose of the Study:

• To investigate the predictive capacity of pulmonary function tests (PFTs) for the development of acute mountain sickness (AMS).
• To assess correlations between spirometry measurements and AMS incidence and severity.

Main Methods:

• A blinded prospective observational study was conducted during a randomized controlled trial on White Mountain, CA.
• Spirometry measurements, including forced expiratory volume in one second (FEV1), forced vital capacity (FVC), and peak expiratory flow, were recorded at baseline (1,250m) and after ascent to high altitude (3,810m).
• Data were analyzed for correlations with AMS, assessed using the Lake Louise Questionnaire.

Main Results:

• One hundred three participants were analyzed; 73% experienced AMS, and 47% had severe AMS.
• No statistically significant associations were found between changes in spirometry values and the incidence of AMS or severe AMS.
• Lake Louise Questionnaire scores showed a negative correlation with FVC (r = -0.31) and FEV1 (r = -0.29) on the night of ascent. Baseline PFTs had a predictive accuracy of 65%-73% for AMS.

Conclusions:

• Spirometry measurements did not show significant changes upon ascent to high altitude, nor were they significantly associated with AMS incidence or severity.
• Low-altitude spirometry did not accurately predict the development of AMS.
• PFTs should not be recommended for risk stratification of acute mountain sickness.