Systematic review of the incidence and risk factors of high-altitude sickness

TANG Qiutong; LI Fulan; XIE Haixia; HAN Ruijuan

doi:10.3969/j.issn.1002-266X.2025.11.016

Abstract：Objective To systematically evaluate the incidence and risk factors of high-altitude sickness,and to pro-vide evidence-based basis for the prevention and treatment of high-altitude sickness.Methods A comprehensive litera-ture search was conducted across both Chinese and English databases,including PubMed,Science Direct,Web of Sci-ence,Wiley Journals,Cochrane Library,Embase,CINAHL,CNKI,VIP,SinoMed,and Wanfang Data,to identify stud-ies investigating the incidence of high-altitude sickness and its influencing factors.The search timeframe spanned from the inception of each database to January 10,2025.Two researchers independently screened literatures and extracted data,and evaluated the quality of the included studies.Meta-analysis was performed using Stata 17.0 software.The data were combined by fixed effect or random effect model,and the publication bias was determined by Egger's rank correlation test and funnel plot.Descriptive analysis was used to analyze the influencing factors.Results A total of 21 studies involving 13,537 participants were included.Meta-analysis results showed that the pooled incidence rate of high-altitude sickness was 37%(95%CI:0.30-0.45).Subgroup analysis revealed that the pooled incidence rate was higher in groups diagnosed using the Lake Louise Score(LLS)or Principle of Diagnosis and Treatment of Benign Form of Acute Mountain Sickness(GJB1098-91)(40%)than those diagnosed using the Qinghai Criteria(22%).The pooled incidence was higher in mili-tary personnel(39%)than in general populations(34%)and mountaineers(33%).The incidence was higher in people who rapidly ascended to high altitude(39%)than in those who underwent staged acclimatization(35%).The incidence in regions with an altitude>4,000 m(43%)was higher than that in regions at 3,000-4,000 m(35%).Factors influencing the incidence of high-altitude sickness included physiological factors[older age,male sex,body mass index≥28 kg/m²,nocturnal pulse oxygen saturation(SpO₂)<85%,and poor sleep quality],environmental and behavioral factors(rapid as-cent to high altitude,high altitude,low atmospheric pressure,and increased annual temperature range,smoking,and al-cohol consumption),and psychological and social factors(abnormal scores on the symptom checklist,military personnel and individuals airlifted to high-altitude areas).The funnel plot showed a symmetrical distribution of points.Egger's test indicated no significant publication bias(P>0.05).Conclusion The incidence of high-altitude sickness is 37%,and it is closely associated with various physiological,environmental,behavioral,and psychological factors.