Skip to main navigation
Skip notifications
Access to POEMs and Essential Evidence Plus will no longer be included in CMA membership as of Dec. 1, 2023.
Search
Single question is useful for identifying acute mountain sickness in travelers at high altitude
Clinical Question
How accurate are diagnostic tools in identifying high-altitude travelers at risk of acute mountain sickness?
Bottom line
Three different diagnostic scoring tools have similar accuracy for identifying adults at risk of acute mountain sickness (AMS). One tool, the Clinical Functional Score (CFS), is the simplest to use and consists of asking a single question. 2b
Reference
Study design: Systematic review
Funding: Foundation
Setting: Various (meta-analysis)
Synopsis
These investigators searched without language restrictions multiple databases including MEDLINE, EMBASE, and bibliographies of relevant articles for studies reporting epidemiological data, evaluations, and comparisons of diagnostic procedures or instruments for AMS. Two investigators independently evaluated potential studies for inclusion criteria and methodologic quality using a standard risk-of-bias scoring tool. Disagreements were resolved by consensus agreement with a third reviewer. The Lake Louise Questionnaire Score (LLQS) is the accepted reference standard for diagnosing AMS, with a score of 5 or higher indicating severe AMS and a corresponding high risk of developing life-threatening high-altitude cerebral edema. The three instruments that could be compared with the LLQS were the Acute Mountain Sickness-Cerebral score (AMS-C), a visual analog scale score quantifying an overall severity of sickness at altitude (VAS[O]), and a clinical functional score (CFS) composed of a single question: "Overall if you had any symptoms, how did they affect your daily activity?" The CFS is scored on an ordinal scale of 0 to 3, indicating none, mild, moderate, and severe (bed rest) reduction in function. A total of 91 articles (N = 66,944 patients) evaluated the prevalence of AMS, reporting that above 2500 m (8200 ft), for every 1000-m increase (3300-ft increase) in altitude, the prevalence of AMS increases by 13% (95% CI 9.5% - 17%). Fourteen studies included head-to-head comparisons of at least 2 different AMS diagnostic tools. Using the LLQS score of 5 or greater as the reference standard, likelihood ratios were similar for the VAS(O), AMS-C, and CFS (positive likelihood ratio range 3.2 - 8.2; and negative likelihood ratio range 0.30 - 0.36). A response of 2 or higher on the single-question CFS (indicating moderate to severe reduction in function) had a pooled sensitivity of 82% and specificity of 67%.
Reviewer
David C. Slawson, MD
Professor and Vice Chair of Family Medicine for Education and Scholarship
Atrium Health
Professor of Family Medicine, UNC Chapel Hill
Charlotte, NC
Comments
Good poem
As neurosurgeon I have been asked if there is any way that can recognize a person who will develop high mountain sickness and I have searched and talked to sport medicine and anesthesiologist who was speciased on diving disorders like decompression and so on , This study also make diagnosis when sickness start,
Really we don't have tool to predict who will get sick, So my recommendation they should be familiar with early and late symptoms of HMS and stop activity when the develop one. as far as I know frontal headache initially mild then gradually sever , brain fug , disorientation could be early symptoms.
I would like to learn if there is any predictor for HMS.
bad poem