Women at Altitude: Effect of Menstrual-Cycle Phase on Acute Mountain Sickness During Deployment to High Altitude Terrain

Abstract

m DISCLAIMERApproved for public release; distribution is unlimited.The views, opinions and/or findings in this report are those of the authors, and should not be construed as an official Department of the Army position, policy or decision, unless so designated by other official documentation.The investigators have adhered to the policies for protection of human subjects as prescribed in Army Regulation AR 70-25.Citations of commercial organizations and trade names in this report do not constitute an official Department of the Army endorsement or approval of the products or services of these organizations.REPORT Public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources garnering and maintaining the data needed, and completing and reviewing the collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden, to Washington Headquarters Services, Directorate for Information Operations and Reports, 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302, and The physiologic responses to the cyclic fluctuations in ovarian steroid hormones associated with the menstrual cycle in women are well known to affect certain disease states and could alter responses to environmental Stressors. Rapid deployment to high mountain terrain induces acute mountain sickness (AMS), which can be an important source of performance decrements and Disease and Non-Battle Injury loss of personnel in military units. To determine the effect of menstrual cycle phase on the occurrence of AMS, symptoms were assessed in 39 women aged 18 to 33 years with normal menstrual cycles who were expose«: to 4300 m altitude continuously on the summit of Pikes Peak, CO for 12 days or in a hypobaric chamber for 60 hours during the early follicular (follicular phase group) or luteal phase (luteal phase group) of their menstrual cycle. The clinical course of AMS in these women was similar to that reported previously in men. Overall, more than 60% of the women in this study experienced AMS during the first 24 hours of altitude exposure. There were no statistically significant differences between symptom scores of the follicular and luteal phase groups. However, the prevalence of AMS was slightly lower in the luteal phase compared to follicular phase volunteers. We conclude that effects of menstrual cycle phase are too small to be of practical significance for most women involved in military operations or civilian recreational pursuits at altitudes up to 4300 m.14. SUBJECT TERMS altitude illness, hypoxia, women, menstrual cycle, progesterone, estradiol, luteal, follicular Major funding for the project reported here came from DWHRP Extramural Grant #DAMD17-95-C-5110 entitled "Women at altitude: Effects of menstrual cycle phase and alpha-adrenergic blockade on high-altitude acclimatization." Additional funding was from D...

Effects of Intermittent Altitude Exposures on Acclimatization of 4,300 M

“…We also found no When comparing the frequency and severity of signs and symptoms of AMS in our study to the results from three previous studies on individuals residing at 4,300 m for 3-wk (Table 11), we found that intermittent exposures to 4,300 m were equally as effective as chronic altitude residence in eliminating the severity and frequency of AMS. The incidence of AMS (i.e., 50%) in our study was comparable to the mean results reported in other studies at this altitude (31,59,84,85). The highest AMS-C score in our study occurred at 12-h post exposure and was comparable to the mean highest AMS-C score reported from these four chronic altitude residence studies (Table 11).'…”

Validation of a Shortened Electronic Version of the Environmental Symptoms Questionnaire

“…An attempt was made to address some of these problems by administering the ESQ-III using a computer software program, but this program was not validated against the paper and pencil version (Fulco et al, 1985). Although a shorter (5-item) paper and pencil questionnaire to assess AMS (Lake Louise [LL] AMS Scoring System) exists and has been validated against the ESQ-III (Savourey et al, 1995;Maggiorini et al, 1998), the LL questionnaire tends to overestimate AMS compared to the ESQ-III (Rock et al, 2001;Bartsch et al, 2004). To eliminate the administrative problems with the paper and pencil ESQ-III and overestimation of AMS by the LL questionnaire, a shortened (11-item) version of the ESQ was developed that could be administered on a hand-held computer.…”

Hormonal Contraceptives and Travel to High Altitude

“…The incidence of AMS does not differ by gender (Hackett and Roach, 2001;Bartsch and Swenson, 2013) and the phase of the menstrual cycle does not influence the incidence of AMS in women (Rock, 2001). However, healthy premenopausal women have fewer apneic-hypopneic events during sleep than healthy men at high altitude (Caravita et al, 2014).…”