Prospective study on effect of body composition increase on bone age development in children aged 3 to 10 years

Abstract

Objective To verify the influence of body composition content and different distribution on bone age development, and establish a healthy lifestyle that benefits bone age development. Methods The prospective cohort study was conducted in the children aged 3 to 10 years at the outpatient and the body component analysis and bone age evaluation were tested during January 1st, 2014 to August 31th, 2015 at the Department of Child Health Care, Wuhan Children′s Hospital(Wuhan Maternal and Child Healthcare Hospital), Tongji Medical College, Huazhong University of Science & Technology, and they were followed up for 1 year.During the follow-up of body weight, height, body composition and bone age, the effect of different body composition distribution and the increase rate on bone age development was investigated. Results Total 341 children were selected, of whom 166 cases were male, 175 cases were female, and their mean age were 3.3-10.8 years.The annual growth rate of bone age ranged from 0.62 to 1.37 years in different age groups.Adipose tissue was the fastest growing composition(2.60 kg/year), followed by lean body tissue(2.47 kg/year), while the slowest growing composition was bone mineral(0.14 kg/year). The prospective factors for fast bone age growth were the content of lean body tissue(β=14.13), skeletal muscle(β=12.79), bone minerals(β=6.26), salts(β=5.91) and lean body tissue of four limbs(1.74≤β≤20.79), longer circumferences of chest(β=2.02), abdomen(β=1.37), and left arms(β=1.36), more fat thickness of abdomen(β=13.10), right and left arms(β=9.47, 6.07)(all P<0.01). On the other hand, the obstructive factors of fast bone age growth were higher content of total body water(β=-5.99), extracellular fluid(β=-1.60), trunk lean body tissue(β=-7.67), and longer circum-ferences of right and left thighs(β=-1.81, -1.77), and high fat thickness of left thighs(β=-7.99)(all P<0.05). Conclusions A healthier lifestyle can defer bone development effectively, such as long-term aerobic exercise, less weight-bearing movement of the limbs (especially in upper limbs), and more water intake, which may result in a taller ultimate height. Key words: Child; Body component increasing velocity; Bone age development; Prospective study