McIntosh Scott E, Hemphill Mika, McDevitt Marion C, Gurung Tsering Yangzom, Ghale Mukhiya, Knott Jonathan R, Thapa Ghan Bahadur, Basnyat Buddha, Dow Jennifer, Weber David C, K Grissom Colin
University of Utah Health, Division of Emergency Medicine, Salt Lake City, UT.
Red Deer Rural Family Medicine, University of Alberta, Edmonton, Alberta, Canada.
Wilderness Environ Med. 2019 Mar;30(1):12-21. doi: 10.1016/j.wem.2018.09.002. Epub 2019 Jan 8.
North American guidelines propose 125 mg acetazolamide twice daily as the recommended prophylactic dose to prevent acute mountain sickness (AMS). To our knowledge, a dose lower than 125 mg twice daily has not been studied.
We conducted a prospective, double-blind, randomized, noninferiority trial of trekkers to Everest Base Camp in Nepal. Participants received the reduced dose of 62.5 mg twice daily or the standard dose of 125 mg twice daily. Primary outcome was incidence of AMS, and secondary outcomes were severity of AMS and side effects in each group.
Seventy-three participants had sufficient data to be included in the analysis. Overall incidence of AMS was 21 of 38 (55.3%) in reduced-dose and 21 of 35 (60.0%) in standard-dose recipients. The daily incidence rate of AMS was 6.7% (95% CI 2.5-10.9) for each individual in the reduced-dose group and 8.9% (95% CI 4.5-13.3) in the standard-dose group. Overall severity of participants' Lake Louise Score was 1.014 in the reduced-dose group and 0.966 in the standard-dose group (95% CI 0.885-1.144). Side effects were similar between the groups.
The reduced dose of acetazolamide at 62.5 mg twice daily was noninferior to the currently recommended dose of 125 mg twice daily for the prevention of AMS. Low incidence of AMS in the study population may have limited the ability to differentiate the treatment effects. Further research with more participants with greater rates of AMS would further elucidate this reduced dosage for preventing altitude illness.
北美指南建议，预防急性高原病（AMS）的推荐预防剂量为乙酰唑胺每日两次，每次125毫克。据我们所知，尚未对低于每日两次125毫克的剂量进行研究。
我们对前往尼泊尔珠峰大本营的徒步旅行者进行了一项前瞻性、双盲、随机、非劣效性试验。参与者接受每日两次62.5毫克的减量剂量或每日两次125毫克的标准剂量。主要结局是AMS的发生率，次要结局是每组中AMS的严重程度和副作用。
73名参与者有足够的数据纳入分析。减量剂量组38人中有21人（55.3%）发生AMS，标准剂量组35人中有21人（60.0%）发生AMS。减量剂量组中每个人的AMS每日发生率为6.7%（95%CI 2.5-10.9），标准剂量组为8.9%（95%CI 4.5-13.3）。减量剂量组参与者的路易斯湖评分总体严重程度为1.014，标准剂量组为0.966（95%CI 0.885-1.144）。两组间副作用相似。
对于预防AMS，每日两次62.5毫克的乙酰唑胺减量剂量不劣于目前推荐的每日两次125毫克的剂量。研究人群中AMS的低发生率可能限制了区分治疗效果的能力。对更多AMS发生率更高的参与者进行进一步研究将进一步阐明这种预防高原病的减量剂量。
