Objective: To explore the association of lean body mass (LBM), lean body mass index(LBMI), fat mass (FM) and fat mass index(FMI) with depressive symptoms in adults aged 65 and above in 18 longevity areas in China. Methods: A cross-sectional study. The study participants were from the Chinese Longitudinal Healthy Longevity Biomarker Cohort Study, comprising elderly individuals aged 65 years and above. Demographic characteristics, lifestyle factors, physical function status, and disease history were collected. Depressive symptoms were assessed using the 9-item Patient Health Questionnaire (PHQ-9). LBM and FM were measured to calculate LBMI and FMI, respectively. Participants were categorized into the depressive group and non-depressive group based on whether the PHQ-9 score≥10 points, and the differences in LBM, LBMI, FM, and FMI between the two groups were compared. Restricted cubic spline models were used to illustrate exposure-response relationships between LBM, LBMI, FM, FMI and the presence of depressive symptoms. Participants were categorized into low, moderate, and high groups based on the tertiles of LBM, LBMI, FM and FMI, respectively, and multivariable logistic regressions were applied to examine the associations of LBM, LBMI, FM, and FMI with depressive symptoms. Results: A total of 4 246 older adults were included, with 2 034 males (47.9%) and a mean age of (81.8±10.2) years. In the non-depressive group (n=4 008), the mean age was (81.9±10.2) years, with 1 957 males (48.8%). In the depressive group (n=238), the mean age was (80.8±9.6) years, with 77 males (32.4%). The LBM of the depvessive group was lower than that of the non-depressive group [(36.8±6.8) kg vs (39.0±7.5) kg, P<0.001]. Restricted cubic spline analysis indicated no non-linear exposure-response relationships between LBM, LBMI, FM, FMI, and the presence of depressive symptoms (all P>0.05). Multifactor logistic regression analysis showed that LBM and LBMI were negatively associated with the risk of depression (all P<0.05). Compared with the low LBM (or LBMI) group, the high LBM group (OR=0.458, 95%CI: 0.291-0.715) and the high LBMI group (OR=0.646, 95%CI: 0.442-0.939) had a lower likelihood of experiencing depressive symptoms. No statistically significant associations were found between FM, FMI, and depressive symptoms (all P>0.05). Conclusion: Among adults aged 65 years and above in longevity regions of China, higher LBM and LBMI are negatively associated with the risk of depressive symptoms.
目的： 探索我国18个长寿地区65岁及以上老年人瘦体重（LBM）、瘦体重指数（LBMI）、脂肪量（FM）及脂肪量指数（FMI）与抑郁症状的关系。 方法： 横断面研究。研究对象来自中国老年健康生物标志物队列，纳入65岁及以上老年人。收集人口学特征、生活方式、身体功能状态及病史信息，采用患者健康问卷-9（PHQ-9）评估抑郁症状，测量LBM和FM，并计算LBMI及FMI。根据PHQ-9总分是否≥10分将研究对象分为抑郁组和无抑郁组，比较两组间LMB、LBMI、FM及FMI差异。采用限制性立方样条绘制LMB、LBMI、FM及FMI与存在抑郁症状的暴露-反应关系曲线。分别根据LBM、LBMI、FM及FMI的三分位数将研究对象划分为低、中、高三组，并通过多因素logistic回归探讨LMB、LBMI、FM及FMI与抑郁症状的关联。 结果： 共纳入4 246名老年人，年龄（81.8±10.2）岁，男2 034名（47.9%）。无抑郁组4 008名，年龄（81.9±10.2）岁，男1 957名（48.8%）；抑郁组238名，年龄（80.8±9.6）岁，男77名（32.4%）。抑郁组LBM低于无抑郁组［（36.8±6.8）kg比（39.0±7.5）kg，P<0.001］。限制性立方样条回归模型显示，LBM、LBMI、FM及FMI与存在抑郁症状间无非线性暴露-反应关系（均P>0.05）。多因素logistic回归模型分析显示，LBM及LBMI与抑郁风险呈负相关（均P<0.05）。与低LBM或低LBMI组相比，高LBM组（OR=0.458，95%CI：0.291~0.715）和高LBMI组（OR=0.646，95%CI：0.442~0.939）存在抑郁症状的概率更低。FM及FMI与抑郁症状之间无明显关联（均P>0.05）。 结论： 中国长寿地区65岁及以上老年人的LBM和LBMI与抑郁风险呈负向关联。.