Age at adiposity rebound is associated with fat mass in young adult males-the GOOD study

Abstract

Objective: Age at adiposity rebound (AR) is associated with obesity and Type 2 Diabetes in adults. The aim of the present study was to investigate the role of age at AR in adult fat mass, fat distribution and pubertal timing for a Swedish cohort.

Patients and methods: This is a retrospective cohort study. Detailed growth charts were retrieved for the men participating in the population-based GOOD (Gothenburg Osteoporosis and Obesity Determinants) study (n=573). Body composition was analysed using dual X-ray absorptiometry and computed tomography at 18-20 years of age. Age and BMI at AR were calculated using pediatric growth charts and AR was defined as the lowest BMI between 3 and 9 years of age.

Results: Subjects were divided into early (age at AR below 5.4 years of age), middle (age at AR 5.4 to 6.8 years of age) and late (age at AR after 6.8 years of age) age at AR tertiles. Subjects in the early age at AR tertile had higher young adult BMI (+8%), whole body fat mass (+34%) and amount of subcutaneous adipose tissue (+61%) than the subjects in the middle and late tertiles (p<0.01). The early age at AR tertile had an increased risk of obesity (Odds Ratio 4.1 [95% CI 1.2-13.9]) compared with the middle and late tertiles. In addition, the early age at AR tertile had Peak Height Velocity (PHV) 7 months earlier than the late tertile.

Conclusions: Early age at AR was associated with young adult obesity as a consequence of a high amount of subcutaneous adipose tissue in men. In addition we made the novel observation that early age at AR was associated with an early puberty in men.

Figure 1. Flowchart of study.

GOOD = Gothenburg Osteoporosis and Obesity Determinants Study, AR = Adiposity Rebound, CT = Computed Tomography.

Figure 2. Childhood BMI plotted for tertiles of age at AR.

Values are given as means. BMI = Body Mass Index, AR = Adiposity rebound. p<0.001 from 6 years of age for the middle and late AR tertiles versus the early AR tertile. p<0.05 from 7 years of age for the late AR tertile versus the middle, and for middle AR tertile versus early at 4 years of age.

Figure 3. Standardized childhood BMI for early age at AR versus middle and late age at AR.

Values are given as Z-score (SD) means ± SEM. BMI = Body Mass Index, AR = Adiposity rebound. *p<0.05, **p<0.01 and ***p<0.001 vs. middle and late tertiles.

Figure 4. Fat parameters according to age at AR tertiles.

Histograms representing early, middle and late age at adiposity rebound tertiles for BMI (a), percentage body fat (b), whole body fat mass (c), serum leptin levels (d), Subcutaneous adipose tissue (ScAT; n = 194; e) and Intraperitoneal adipose tissue (IpAT; n = 194; f). Values are given as means ± SEM. BMI = Body Mass Index, **p<0.01, ***p<0.001.