Adiposity, Insulin Resistance, Cardiorespiratory Fitness, and Bone Health in Hispanic Children

Authors

Reem S Shawar
Maurice Puyau
Roman Shypailo
Salma Musaad
Nancy F Butte
Fida Bacha

Publication Date

8-18-2022

Journal

The Journal of Clinical Endocrinology and Metabolism

DOI

10.1210/clinem/dgac344

PMID

35662345

PMCID

PMC9387690

PubMedCentral® Posted Date

6-6-2022

PubMedCentral® Full Text Version

Post-print

Published Open-Access

yes

Keywords

Absorptiometry, Photon, Adiposity, Adolescent, Body Mass Index, Bone Density, Cardiorespiratory Fitness, Child, Cross-Sectional Studies, Female, Hispanic or Latino, Humans, Insulin Resistance, Male, Pediatric Obesity, insulin resistance, adiposity, bone mineral content, cardiorespiratory fitness

Abstract

CONTEXT: Childhood obesity disproportionately affects Hispanic youth. The skeletal system appears to be a target organ of the adverse effects of obesity. Yet, the relationship between adiposity and bone health in youth and the modulating factors are not well understood.

OBJECTIVE: This work aims to examine the relationship between adiposity, insulin resistance (IR), cardiorespiratory fitness (CRF), and bone mass in Hispanic youth.

METHODS: A total of 951 Hispanic youth (50% male), aged 4 to 19 years, participated in this cross-sectional design study from the Viva La Familia Study at Children's Nutrition Research Center. Bone mineral content (BMC) and density (BMD), lean mass (LM), total body fat mass (FM), truncal FM were obtained using dual-energy x-ray absorptiometry. Fasting glucose and insulin were obtained and the homeostasis model assessment of insulin resistance (HOMA-IR) was calculated. CRF was measured using a treadmill ramp protocol. We applied linear regression models and mediation analyses.

RESULTS: Adiposity measures were negatively related to BMC and BMD after accounting for LM and sex. IR negatively contributed whereas CRF positively contributed to the variance in BMC and BMD, more notably in the pubertal age group. In mediation analysis, HOMA-IR partially mediated the negative relationship of adiposity to BMC (standardized indirect effect [IE] = -0.0382; 95% CI, -0.0515 to -0.0264) whereas the sequential IE of HOMA-IR and CRF partially attenuated (IE = -0.0026; 95% CI, -0.0053 to -0.0005) this relationship. Similar findings were seen with BMD as the primary outcome.

CONCLUSION: IR mediates the negative relationship between adiposity and bone mass whereas CRF may partially attenuate it.