Table 2.

Characteristics of the study group.

	Exposed (n = 48)	Controls (n = 33)
Age (mean ± SD)	37.77 ± 10.23	36.73 ± 9.50
Sex*
Male	41	19
Female	7	14
Smoking
Smokers	12	4
Non-smokers	36	29
Altitude, above sea level*
<2500 m	21	22
>2500 m	27	11

^*Significant differences between referent and exposed groups (p < 0.01)