Association between prior COVID-19 infection and acute mountain sickness on Jade Mountain: A prospective observational study (2023−2024)

BACKGROUND: Acute mountain sickness (AMS) is a frequent concern for climbers at high altitudes. Since the COVID-19 pandemic, questions have emerged regarding whether prior infection increases susceptibility to AMS. METHODS: We conducted a prospective observational study at the Paiyun Lodge medical station (3402 m) on Jade Mountain (Yushan, 3952 m) between 2023 and 2024. All climbers presenting for medical services were screened. Demographics, comorbidities, ascent characteristics, sleep duration, prophylactic medication, and self-reported COVID-19 history were recorded. AMS was diagnosed clinically and validated using the 2018 Lake Louise AMS Score. Logistic regression and multiple propensity score methods were used to assess associations between COVID-19 history and AMS occurrence and severity. RESULTS: A total of 871 patients were included; 52.4 % were aged 20-40 years, 57.3 % were male, and 74.7 % reported a history of COVID-19 infection. Clinically diagnosed AMS occurred in 64.1 % (n = 558), with 274 mild and 284 severe cases. Although crude analyses suggested a borderline association between COVID-19 history and AMS (OR = 1.36, 95 % CI: 1.00-1.87), this was not statistically significant after multivariable adjustment (adjusted OR = 1.34, 95 % CI: 0.96-1.88) or propensity score methods. CONCLUSION: Prior COVID-19 infection was not significantly associated with the occurrence and severity of AMS among climbers who sought medical services on Jade Mountain. These findings suggest that a history of mild COVID-19 does not independently increase AMS susceptibility, providing reassurance to mountaineers and aligning with contemporary expert consensus.