Obesity: associations with acute mountain sickness.

BACKGROUND

Although few retrospective studies of high altitude have reported that obesity might be associated with the development of acute mountain sickness (AMS), this association has not been studied prospectively.

OBJECTIVE

To determine whether obesity is associated with the development of AMS.

DESIGN

Obese and nonobese men were compared at a simulated altitude of 3658 m (12 000 ft).

SETTING

24 hours in a hypobaric environmental chamber.

PARTICIPANTS

9 obese and 10 nonobese men.

MEASUREMENTS

Percentage body fat (by hydrostatic weighing), Lake Louise AMS score, and Sao2 level (by pulse oximetry) were measured.

RESULTS

Average AMS scores increased more rapidly with time spent at simulated high altitudes for obese men than for nonobese men (P < 0.001). The response of Sao2 with exposure differed between nonobese and obese men. After 24 hours in the altitude chamber, seven obese men (78%) and four nonobese men (40%) had AMS scores of 4 or more.

CONCLUSION

Obesity seems to be associated with the development of AMS, which may be partly related to greater nocturnal desaturation with altitude exposure.