[Hemoglobin changes (Hb) in miners exposed to high altitude and associated factors]

To determine the variation of hemoglobin (Hb) in two groups of miners working at different altitudes.

A longitudinal study conducted in a private company. Hb was obtained from entrance exams and annual checks of workers at two locations: at sea level and at Peruvian highlands (4,100 m), taken by trained staff and equipment calibrated to environmental conditions. We analyzed variations in the course of the years with the PA-GEE statistical test; p values were obtained.

Of the 376 workers, 89% (322) were men, the median age was 32 years (range 20-57) and 84% (304) were at high altitude. In multivariate analysis, male sex (p < 0.001), body mass index (BMI; p = 0.021) and working at high altitude (p < 0.001) were associated with the greatest variation of Hb in time, adjusted for age, length, and type of work.

These findings should be considered for health surveillance of workers exposed to similar conditions to prevent chronic mountain sickness.

The change in Hb of miners was associated with male sex, BMI, and work at high altitude.