Biochemical adaptations to moderately high altitude living

Abstract

Human adaptation to moderately high altitude living produces physiological changes. We examined blood chemistry values in 46 male and 30 female natives residing at 3000 m and compared them to an adult population not matched for age (44 men and 40 women) residing at sea level. The following values were significantly lower (p<0.05) in the high altitude subjects: serum glucose, magnesium, bicarbonate, creatinine and high density lipoprotein. Serum potassium, triglycerides, amylase, aspartate aminotransferase and alkaline phosphatase levels were found to be significantly (p<0.05) higher. The authors did not detect hyperuricemia in any subject. Serum calcium and phosphorus concentrations were significantly higher (p < 0.05) in the high altitude women, corresponding to higher serum protein. In a subgroup of high altitude subjects (22 men and 18 women), total T4 and free T3 and T4 were significantly higher (p<0.05), and thyroid binding globulin (TBC) lower (p<0.05) compared to sea level subjects. The gamma globulins, notably IgA, were increased in the high altitude subjects. Iron binding capacity was elevated in women at high altitude. Detailed metabolic studies to elucidate the reason(s) for differences between high altitude and sea level individuals might enhance our understanding of the chronic effects of mild hypoxemia.