Acculturation and the growth of lung function: three cross-sectional surveys of an Inuit community

The influence of acculturation to a sedentary lifestyle upon the growth and development of lung volumes has been studied in Inuit children aged 9-19 years. Surveys were conducted in the circumpolar community of Igloolik (69 degrees 40'N, 81 degrees W) in 1969/70, 1979/80 and 1989/90. Over this period, the children showed little change of height or body mass at any given age, but a progressive loss of what initially had been a high level of health-related fitness. The sample for each survey comprised about 70% of children in the chosen age range: in the most recent study 87 males and 65 females. Respiratory data included forced vital capacity, one-second forced expiratory volume, maximal mid-expiratory flow rate (second and third surveys only), smoking habits and respiratory health. In each of the 3 surveys, many of the older children in the community were regular smokers. The average cigarette consumption currently rises progressively to 13 +/- 8 cigarettes/day in 87% of males and 11 +/- 7 cigarettes/day in 95% of females over 17 years of age. Nevertheless, lung volumes show the anticipated increase as a logarithmic function of stature. Furthermore, statistically fitted curves show only minor inter-survey differences in volumes for a given standing height. We thus conclude that the deterioration in other aspects of health-related fitness has not yet influenced the growth and development of respiratory function within this Inuit population.