Change of plasma high sensitive - C reactive protein levels in climbers

Rationale: Acute mountain sickness (AMS) is a high altitude illness. Previous studies report that levels of inflammatory indicators are higher at high altitudes. Therefore, inflammation is important for AMS. Objectives: We examined whether slight inflammation in mountain climbers could be detected with plasma levels of high sensitive C-reactive protein (hs-CRP). Next, we studied the relations of clinical parameters of plasma hs-CRP levels in AMS patients. Methods: (A) 32 healthy subjects were recruited to climb the mountain. We collected their blood in Tokyo (about 40 m above sea level) and in Mt. Kita Clinic (about 2,900 m above sea level). We measured plasma hs-CRP levels in their samples. (B) Next, we collected blood from 21 climbers diagnosed with AMS. We also measured hs-CRP levels in AMS patients and examined their relationship to clinical parameters of AMS. Results: Plasma hs-CRP levels of healthy subjects after climbing the mountain were significantly higher than before climbing (914±272 ng/ml vs 299±86, P<0.05). Plasma levels of hs-CRP were much higher values in AMS patients (2,433±831). They were correlated with AMS score (P<0.001, r=0.658), and symptomatic duration (P<0.001, r=0.691). Conclusion: These results showed slight inflammation existed in healthy climbers. Moreover, it was demonstrated plasma hs-CRP levels were related to clinical parameters of AMS. Therefore, hs-CRP was suggested to be an available and objective marker that could be used to evaluate the severity of AMS as an inflammatory disease.