ANTHROPOMETRIC VARIABLES AFFECTING HEMOGLOBIN LEVELS IN HIGH AND LOW-ALTITUDE POPULATIONS

Objectives: To determine the mean level of hemoglobin in a selected gr oup of native highlanders and to compare it with their counterparts li ving at lowland and also to identify the relevant anthropometric varia bles which may affect the mean hemoglobin level in high and lowlanders . Method: Cross-sectional, randomized prospective study of 150 healthy normal Saudi Arab males, born and living permanently at high altitude , Alsoda (3150 meters above sea level) and 218 healthy normal Saudi Ar ab males born and living permanently at low altitude, Alraish (500 met ers above sea level) villages in southern Saudi Arabia. Estimates of h emoglobin levels and hematocrit values (using cyanmethemoglobin method and microhematocrit tubes and centrifuges respectively) and measureme nt of weight, stature, midupperarm circumference and triceps skinfold thickness (using an Avery Beam Weighing Scale, Stadiometer, a fiber gl ass tape and Harpenden Caliper respectively) were made on high and low landers. Tn both groups estimates of fat mass and Fat free mass were m ade from the triceps skinfold measurements. Results: The mean hemoglob in level was significantly greater in highlanders (17.0 gm/dl +/- 1.2) than in lowlanders (14.1 gm/dl +/- 1.0) (P < 0.001). In both groups h emoglobin was found to be positively and significantly associated with hematocrit, stature, weight and fat free mass. Conclusion: The differ ence in hemoglobin levels between high and lowlanders was attributed t o the enhanced erythropoietic drive of the chronic hypoxia of high alt itude and possibly also to the higher incidence of tropical infections in lowlanders.