Influence of Developmental Adaptation on Lung Function at High Altitude

The Forced Vital Capacity (FVC) was measured on a total sample of 104 subjects and residual lung volume (RV) was measured on a total of 36 subjects living at 3840m and 3400m altitude in southern Peru. The Forced Vital Capacity (FVC) of the high altitude natives, when adjusted for age, height and weight by covariance analyses, significantly exceeded the values attained by sea level subjects acclimatized to high altitude in the adult stage. In contrast, the FVC of the sea level subjects acclimatized to high altitude in the developmental period was comparable to those attained by the high altitude natives. These findings suggest that the attainment of increased forced expiratory lung volumes at high altitude are probably influenced by adaptations which occurred during the developmental period .The high altitude natives tested at 3840m, despite their markedly smaller body size, attained a significantly greater mean residual lung volume than U.S.A. sea level subjects. It is quite possible that the increased residual lung volume at high altitude may also be influenced by developmental factors. However, further research is necessary in order to define the components of increased residual lung volumes at high altitude. Among high altitude natives, the best prediction of FVC was obtained from a regression equation which included the subject’s chest circumference at maximum inspiration, height, weight, and age. For total lung capacity the best predictive equation included the subject’s forced vital capacity, chest volume, ponderal index, and age.