Hypoxia-induced impairments in fasting glucose are associated with acute mountain sickness severity during 4 days of residence at 4,300 m
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View abstract on PubMed
Summary
This summary is machine-generated.High altitude exposure increases insulin resistance, which correlates with acute mountain sickness (AMS) severity. Active ascent did not worsen AMS, but transient glucose metabolism changes influenced severity.
Area Of Science
- Environmental Physiology
- Metabolic Health
- Altitude Medicine
Background
- Insulin resistance is linked to acute mountain sickness (AMS) risk.
- The impact of active ascent on AMS and metabolic changes at high altitude remains unclear.
Purpose Of The Study
- To investigate the relationship between insulin resistance and AMS severity during high altitude exposure.
- To determine if active ascent influences AMS or metabolic responses compared to passive ascent.
Main Methods
- Thirty-two soldiers ascended to 4,300 m, with 16 actively hiking and 16 passively driven.
- Blood samples were collected at baseline and during 4 days at high altitude (HA) to measure glucose, insulin, hormones, and calculate HOMA-IR.
- AMS severity was assessed daily using the AMS cerebral score (AMS-C).
Main Results
- Active ascenders exhibited higher energy expenditure and lower oxygen saturation during ascent.
- Glucose, insulin, and HOMA-IR levels were elevated on HA days 2 and 3 compared to baseline.
- Glucose, insulin, HOMA-IR, epinephrine, and norepinephrine levels significantly correlated with AMS-C scores.
Conclusions
- Transient insulin resistance and glucose metabolism perturbations at high altitude are associated with AMS severity.
- Active ascent did not independently worsen AMS, suggesting metabolic changes are key drivers of severity.
- Cortisol and nocturnal hypoxemia may contribute to blood glucose fluctuations at high altitude.
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