Background Body composition might influence lung function and asthma in children, but its longitudinal relations are unclear. We aimed to identify critical periods for body composition changes during childhood and adolescence in relation to respiratory outcomes in adolescents. Methods In a population-based prospective cohort study, we measured body mass index, fat mass index (FMI), lean mass index (LMI) and the ratio of android fat mass divided by gynoid fat mass (A/G ratio) by dual-energy X-ray absorptiometry at 6, 10 and 13 years. At 13 years, lung function was measured by spirometry, and current asthma was assessed by questionnaire. Results Most prominently and consistently, higher FMI and A/G ratio at age 13 years were associated with lower forced expiratory volume in 1 s (FEV1)/forced vital capacity (FVC) and forced expiratory flow after exhaling 75% of FVC (FEF75) (range Z-score difference −0.13 (95% CI −0.16 to –0.10) to −0.08 (95% CI −0.11 to –0.05) per SD score increase), and higher LMI at all ages was associated with higher FEF75 (range Z-score difference 0.05 (95% CI 0.01 to 0.08) to 0.09 (95% CI 0.06 to 0.13)). Between the ages of 6 and 13 years, normal to high FMI and A/G ratio were associated with lower FEV1/FVC and FEF75 (range Z-score difference −0.20 (95% CI −0.30 to –0.10) to −0.17 (95% CI −0.28 to –0.06)) and high to high LMI with higher FEF75 (range Z-score difference0.32 (95% CI 0.23 to 0.41)). Body composition changes were not associated with asthma. Conclusion Adolescents with higher total and abdominal fat indices may have impaired lung function, while those with a higher lean mass during childhood and adolescence may have better small airway function. Public health measures should focus on a healthy body composition in adolescents to minimise respiratory morbidity. No data are available. The datasets generated and/or analyzed during the current study are not publicly available due to individual privacy consideration, but are available from the data managers (datamanagementgenr@erasmusmc.nl) and Director Generation R, Vincent Jaddoe (v.jaddoe@erasmusmc.nl) after a written agreement about the use of the data made via the Technology Transfer Office of Erasmus MC.

中文翻译：

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儿童的身体成分和呼吸结果：一项基于人群的前瞻性队列研究

背景 身体成分可能影响儿童的肺功能和哮喘，但其纵向关系尚不清楚。我们的目的是确定儿童期和青春期身体成分变化与青少年呼吸结果相关的关键时期。方法 在一项基于人群的前瞻性队列研究中，我们测量了体重指数、脂肪质量指数 (FMI)、瘦体重指数 (LMI) 以及机器人脂肪质量除以雌性脂肪质量的比率（A/G 比率），并通过双6、10 和 13 年的能量 X 射线吸收测定法。 13 岁时，通过肺活量测定法测量肺功能，并通过问卷调查评估当前哮喘状况。结果最显着且一致的是，13 岁时较高的 FMI 和 A/G 比与较低的 1 秒用力呼气量 (FEV1)/用力肺活量 (FVC) 以及呼出 75% FVC 后的用力呼气流量 (FEF75) 相关（范围 Z 分数差异 -0.13（95% CI -0.16 至 –0.10）至 -0.08（95% CI -0.11 至 –0.05）每 SD 分数增加），并且所有年龄段的较高 LMI 与较高的 FEF75 相关（范围Z 分数差异为 0.05（95% CI 0.01 至 0.08）至 0.09（95% CI 0.06 至 0.13））。在 6 岁至 13 岁之间，正常至高 FMI 和 A/G 比值与较低的 FEV1/FVC 和 FEF75 相关（范围 Z 分数差异 -0.20 (95% CI -0.30 至 –0.10) 至 -0.17 (95 % CI -0.28 至 –0.06)) 和从高到高的 LMI，FEF75 较高（范围 Z 分数差异 0.32（95% CI 0.23 至 0.41））。身体成分的变化与哮喘无关。结论 总脂肪指数和腹部脂肪指数较高的青少年可能存在肺功能受损的情况，而儿童期和青春期去脂体重较高的青少年可能有较好的小气道功能。公共卫生措施应侧重于青少年健康的身体成分，以尽量减少呼吸道疾病的发病率。无可用数据。出于个人隐私考虑，本研究期间生成和/或分析的数据集不公开，但可从数据管理人员 (datamanagementgenr@erasmusmc.nl) 和 R 代董事 Vincent Jaddoe (v.jaddoe@erasmusmc.nl) 处获取）在通过 Erasmus MC 技术转让办公室签订有关数据使用的书面协议后。