Growth and Development of Andean High Altitude Residents

Abstract

Growth and development under conditions of chronic hypoxia result in a different pattern of growth in Andean highlanders than in lowlanders. Growth at high altitude results in a small (1 to 4 cm) delay in linear growth, with most, if not all, of the delay probably established at or soon after birth. It also results in an enhancement of lung volumes, particularly residual volume, which is 70%-80% larger in highland than lowland children, on average, with the magnitude of the increase being positively related to age. In addition, growth and development under conditions of chronic hypoxia result in a blunted ventilatory response to hypoxia, a 4% to 5% reduction in Sa(O2), and a substantial increase in pulmonary diffusing capacity. Andean highlanders have V(O2 max) similar to that of lowlanders at low altitude, suggesting that they have successfully adapted to their hypoxic environment. It is likely that both developmental and genetic factors influence most, if not all, components of the cardiorespiratory system of Andean highlanders, but the relative importance of each is not clear.

Effects of Altitude on Anthropometric and Physiological Patterns in Aymara and Non-Aymara Population Between 18 and 65 Years in the Province of Parinacota Chile (3.700 masl)

“…The physiological differences (Table III), shows that cardiac frequency and respiratory frequency tend to decrease in the older age groups, particularly in men of both populations. These results are similar to those found by Greksa (2006) and Beall (2007), who determine that development, the genetic and time of colonization are influential factors in the components of cardiorespiratory adaptation at high altitude although the relative importance of each is still not clear.…”

“…The results obtained for weight and size, show that these indexes are reduced in the Aymara population with respect to their non Aymara peers (p≤ 0.05), similar to findings by other authors, who determined that these differences could be influenced by nutritional conditions and low temperatures common to high elevation regions (Greksa, 2006;Moreno et al, 2006;Julian et al, 2009). These differences are not reflected in the BMI, in which the total population in the study, Aymara and non Aymara is at overweight levels, excepting the Aymara women from 18 to 35 years, who present normal weight indexes.…”

“…The forced vital capacity, does not show significant differences within each of the study groups by sex and Aymara ethnicity. These values could reflect an adaptive mechanism of the cardio respiratory system in the Aymara population and other populations living at high altitudes related with the historical occupation of the highlands (Frisancho, 1999;Kapoor & Kapoor, 2005;Greksa, 2006;Aldenderfer, 2006).…”

“…These anthropometric and physiological differentials note that high altitude populations have a substantial advantage in taking better advantage of the oxygen and the development, genetic, nutrition and intra individual factors are influential for an improved adaptation of the altitude condition, whether it is in the Aymara or the non Aymara population. However the Aymara population in view of its history and endurance at high altitudes is more adapted to a better quality of life in altitudes with respect to the non Aymara population (Rupert & Hochachka, 2001); Greksa, 2006;Gonzales, 2007).…”

“…Other studies determine that the development, genetic and intra-individual factors would influence in a successful adaptation of height of the cardio-respiratory components (Greksa, 2006). The aim of this study was to compare anthropometric and physiological patterns in a sample of 522 Aymara and non-Aymara individuals, separated in two age groups of 18 to 35 years, and 36 to 65 years, in the Parinacota Province who live at 3700 (masl).…”