The adolescent growth spurt of height among rural Indian boys in relation to childhood nutritional background: an 18 year longitudinal study.

The Adolescent Growth Spurt (AGS) was studied in rural Hyderabad boys of 5+ years of age with known childhood nutritional background. Longitudinal data on height measurements of pre-school children available for 13 to 16 points of follow-up, during an 18 year period of study (i.e., from 1965-66 to 1983-84) were utilized for this purpose. A Preece and Baines model 1 (PB 1) function was fitted for height measurements of 323 boys aged 19-24 years in 1984. The boys were classified into three groups according to degree of under-nutrition at the age of 5+ years, using Boston reference values for height. Boys with severe height deficit at age 5+ were considered to have had a background of severe undernutrition and were referred as Group III. Boys with normal range height measurements at age 5+ were considered to have a normal nutritional background and were referred to as Group I. Group II boys had height deficits in between the above two groups and were considered to have milk to moderate undernutrition backgrounds. Group I boys had similar timing, intensity, duration of Adolescent Growth Spurt Period (AGSP) and gained a similar amount of height during puberty as did British boys. Group III boys differed significantly from British boys for AGS. They entered late into puberty, with significantly depressed intensity, but gained a similar amount of height, as a result of prolonged AGSP, which continued till 19.2 years. Thus a childhood background of undernutrition did not lead to any additional deficit in height during puberty. However, pre-pubertal height deficits were carried into adult height. The growth curves of rural Hyderabad children were parallel to the British distance height curve after 12 years of age. The mean constant height velocity curve of group I boys was superimposable on the British curve during puberty.