The Relationships Between Skeletal Muscle Index and Bone Variables in a Group of Young Adults

Anthony Khawaja (1) , Patchina Sabbagh (2) , Jacques Prioux (3) , Gautier Zunquin (2) , Georges Baquet (2) , Ghassan Maalouf (4) , Zaher El Hage (5) , Amal Antoun (1) , Rawad El Hage (1)

1 UOB - University of Balamand [Liban]
2 URePSSS - Unité de Recherche Pluridisciplinaire Sport, Santé, Société (URePSSS) - ULR 7369 - ULR 4488
3 M2S - Laboratoire Mouvement Sport Santé
4 USJ - Université Saint-Joseph de Beyrouth
5 NDU - Notre Dame University-Louaize [Lebanon]

The purpose of this study was to investigate the relationships between skeletal muscle index (SMI) and bone variables in a group of young adults. Three hundred and thirty-five young adults (129 men and 206 women) whose ages ranged from 18 to 35 yr voluntarily participated in this study. Weight and height were measured, and body mass index (BMI) was calculated. Body composition, bone mineral content (BMC), bone mineral density (BMD), geometric indices of hip bone strength and trabecular bone score (TBS) were determined for each individual by Dual-energy X-ray absorptiometry (DXA). Appendicular skeletal mass (ASM, in kg) was calculated by summing the muscle masses of the 4 limbs, assuming that all nonfat and nonebone mass is skeletal muscle. Skeletal muscle index (SMI) was defined as ASM/height². In young men, SMI was positively correlated to WB BMC (r = 0.63; p < 0.001), WB BMD (r = 0.53; p < 0.001), L1-L4 BMC (r = 0.33; p < 0.001), L1-L4 BMD (r = 0.30; p < 0.001), L1-L4 TBS (r = 0.26; p < 0.01), TH BMC (r = 0.61; p < 0.001), TH BMD (r = 0.46; p < 0.001), FN BMC (r = 0.51; p < 0.001), FN BMD (r = 0.46; p < 0.001), FN cross-sectional area (CSA) (r = 0.56; p < 0.001), FN cross-sectional moment of inertia (CSMI) (r = 0.52; p < 0.001) and FN section modulus (Z) (r = 0.54; p < 0.001) but negatively correlated to FN strength index (SI) (r = -0.24; p < 0.01). In young women, SMI was positively correlated to WB BMC (r = 0.61; p < 0.001), WB BMD (r = 0.60; p < 0.001), L1-L4 BMC (r = 0.35; p < 0.001), L1-L4 BMD (r = 0.33; p < 0.001), L1-L4 TBS (r = 0.29; p < 0.001), TH BMC (r = 0.61; p < 0.001), TH BMD (r = 0.53; p < 0.001), FN BMC (r = 0.45; p < 0.001), FN BMD (r = 0.49; p < 0.001), FN CSA (r = 0.60; p < 0.001), FN CSMI (r = 0.52; p < 0.001), and FN Z (r = 0.40; p < 0.001) but negatively correlated to FN SI (r = -0.20; p < 0.01). The current study suggests that SMI is a positive determinant of bone mineral density and geometric indices of hip bone strength in young adults.

Mots clés: Appendicular skeletal mass; DXA; peak bone mass

Domaines: Sciences du Vivant [q-bio]

Anthony Khawaja, Patchina Sabbagh, Jacques Prioux, Gautier Zunquin, Georges Baquet, et al.. The Relationships Between Skeletal Muscle Index and Bone Variables in a Group of Young Adults. Journal of Clinical Densitometry, 2021, 24 (1), pp.78-87. ⟨10.1016/j.jocd.2019.02.007⟩. ⟨hal-02088127⟩