The Aymara of Western Bolivia: V. Growth and development in an hypoxic environment

As a part of the Multinational Andean Genetic and Health Program, the Bolivian Health Survey sought to compare the anatomic, physiologic and biochemical characteristics of Aymara of the Bolivian altiplano (3700-4000 m) to those of Aymara of the Chilean altiplano (4000-4500 m). Presented here are the anthropometric age changes and differences that accompany sex, ethnicity and permanence of residence. Our objective is to assess what physical growth differences, if any, obtain among populations residing in high regions. In height, weight and chest morphology, the two high altitude populations were more similar to each other than either was to a lowland control from the Chilean coast. The high altitude samples tended to exceed coastal controls in some of the chest measurements in spite of a generally smaller body size. This provides support for the idea that hypoxia may induce growth of anatomic features associated with oxygen transport. The two high altitude groups differed in some soft tissue measurements, and this difference was greatest among adults of the samples. These anthropometric differences probably reflect socioeconomic variation among populations at high altitude. Regional differences in environmental factors on the altiplano could influence the outcome of comparisons made between altitudes, and may account for a lack of consistent results among previous studies of the effects of hypoxia on human development.