Relationship between body fat distribution and bone mineral content of adolescents in Yinchuan

Abstract

Objective To analyze the relationship between body fat distribution and bone mineral content (BMC) in adolescents and gender differences among Chinese adolescents, and to provide a scientific basis for the prevention and treatment of bone metabolic diseases.

Methods A total of 1 575 adolescents aged 12–18 years old were selected from Yinchuan by cluster random sampling. Body composition and bone mineral content were measured by bioelectrical impedance analysis (BIA). Multiple linear regression analysis was used to explore the relationship between body fat distribution and BMC after adjusting for confounding factors.

Results Except for LTFR, the levels of FM, AFM, TFM, TrTFR and TrLFR in boys were lower than those in girls ( t = −13.52, −15.18, −12.47, −12.25, −7.96, P<0.05); After adjusting for age, sex and weight, FM, AFM, TFM, TrTFR and TrLFR were all negatively correlated with BMC level ( P<0.05). For each increase of 1 standard deviation in TFM, BMC level decreased by 0.53 standard deviation (95% CI = −0.57− −0.49, P<0.01). LTFR had a linear negative correlation with BMC level in boys ( B = 0.07, P<0.01), no similar correlation was found in girls ( B = 0.01, P = 0.74). There was a linear negative correlation between TrLFR and BMC level in girls ( B = −0.06, P =0.03), but the correlation was of no significance in boys ( B = −0.01, P =0.55).

Conclusion Sex difference in body fat distribution in Chinese adolescents is observed. Body fat distribution is closely related to bone minerals content in adolescents.

Abstract

【摘要】 目的 分析青少年体脂肪分布与骨矿物质含量 (bone mineral content, BMC) 的关系以及在不同性别间的差异, 为 青少年骨代谢疾病的防治提供科学依据。 方法 以整群随机抽样的方法从银川市选取 1 575 名 12~18 岁青少年作为研究 对象, 进行问卷调査、体格检査、体成分及骨矿物质含量测定, 采用多元线性回归分析探讨校正混杂因素后体脂肪分布与 BMC 水平的关系。 结果 除四肢-全身脂肪比 (LTFR) 外, 男生全身脂肪含量 (fat mass, FM)、四肢脂肪含量 (appendicular fat mass, AFM)、躯干脂肪含量 (trunk fat mass, TFM)、躯干-全身脂肪比 (TrTFR)、躯干-四肢脂肪比 (TrLFR) 均低于女生 ( t 值分别为 −13.52, −15.18, −12.47, −12.25, −7.96, P 值均<0.05); 调整年龄、性别和体重后, FM、AFM、TFM、LTFR、TrTFR 均与 BMC 水平呈负相关 ( P 值均<0.05), 其中 TFM 每增加 1 个标准差, BMC 水平下降 0.53 个标准差 (95% CI =−0.57~−0.49, P<0.01)。在男生中, LTFR 与 BMC 水平呈负相关 ( B = −0.07) ( P<0.01), 而在女生中无相关性 ( B = 0.01, P = 0.74); 在女生中, TrLFR 与 BMC 水平呈负相关 ( B = −0.06) ( P =0.03), 而在男生的相关性无统计学意义 ( B = −0.01, P = 0.55)。 结论 青少年体脂肪分布存在性别差异, 且在这一时期, 体脂肪分布与骨矿物质含量显著相关。应多关注青少年体脂肪的分 布, 为提早预防青少年骨代谢疾病提供科学依据。