Table 9.

Testosterone concentrations (nmol/L) at different altitude levels in the whole group of subjects and differences relative to PR.

	Mean ± s.d.	n	Differences relative to Pr (adjusted for SaO2)
			Coefficient ± s.e.	P value	95% CI
PR	21.5 ± 10.1	18
BC1	21.1 ± 13.6	19	−0.5 ± 2.5	0.821	−5.6; 4.4
C2	23.9 ± 13.5	8	1.8 ± 3.4	0.585	−4.8; 8.6
C3	10.7 ± 3.2	6	−10.7 ± 3.7	0.007	−18.1; −3.3
BC2	28.5 ± 10.9	14	7.5 ± 2.7	0.005	2.0; 12.9
PO	18.4 ± 6.4	19	−2.7 ± 2.5	0.285	−7.7; 2.2

Variation of testosterone was not sex or paO₂ but SaO₂ (P = 0.28) dependent.

Altitudes: PR, Pre expedition = 550 m; BC1, Base Camp 1 = 4.844 m; C2, Camp2 = 6022 m; BC2, Base Camp 2 (after acclimatization) = 4.844 m; C3, Camp3 = 7050 m; PO, Post expedition = 550 m.