Department of Environmental Health, Harvard T.H. Chan School of Public Health, Boston, Massachusetts.
Department of Biostatistics, Center for Global Health, School of Public Health, Nanjing Medical University, Nanjing, China.
Cancer Epidemiol Biomarkers Prev. 2022 Jan;31(1):262-268. doi: 10.1158/1055-9965.EPI-21-0503. Epub 2021 Nov 2.
Body mass index (BMI) change after a lung cancer diagnosis has been associated with non-small cell lung cancer (NSCLC) survival. This study aimed to quantify the association based on a large-scale observational study.
Included in the study were 7,547 patients with NSCLC with prospectively collected BMI data from Massachusetts General Hospital and Brigham and Women's Hospital/Dana-Farber Cancer Institute. Cox proportional hazards regression with time-dependent covariates was used to estimate effect of time-varying postdiagnosis BMI change rate (% per month) on overall survival (OS), stratified by clinical subgroups. Spline analysis was conducted to quantify the nonlinear association. A Mendelian Randomization (MR) analysis with a total of 3,495 patients further validated the association.
There was a J-shape association between postdiagnosis BMI change and OS among patients with NSCLC. Specifically, a moderate BMI decrease [0.5-2.0; HR = 2.45; 95% confidence interval (CI), 2.25-2.67] and large BMI decrease (≥2.0; HR = 4.65; 95% CI, 4.15-5.20) were strongly associated with worse OS, whereas moderate weight gain (0.5-2.0) reduced the risk for mortality (HR = 0.78; 95% CI, 0.68-0.89) and large weight gain (≥2.0) slightly increased the risk of mortality without reaching statistical significance (HR = 1.10; 95% CI, 0.86-1.42). MR analyses supported the potential causal roles of postdiagnosis BMI change in survival.
This study indicates that BMI change after diagnosis was associated with mortality risk.
Our findings, which reinforce the importance of postdiagnosis BMI surveillance, suggest that weight loss or large weight gain may be unwarranted.
肺癌诊断后体重指数（BMI）的变化与非小细胞肺癌（NSCLC）的生存有关。本研究旨在通过一项大规模观察性研究来量化这种关联。
纳入了来自马萨诸塞州综合医院和布莱根妇女医院/达纳-法伯癌症研究所的前瞻性收集 BMI 数据的 7547 名 NSCLC 患者。使用具有时间依赖性协变量的 Cox 比例风险回归来估计诊断后 BMI 变化率（每月%）对总生存（OS）的影响，按临床亚组分层。进行样条分析以量化非线性关联。对总共 3495 名患者进行孟德尔随机分析进一步验证了这种关联。
NSCLC 患者的诊断后 BMI 变化与 OS 之间存在 J 形关联。具体而言，中度 BMI 下降（0.5-2.0；HR=2.45；95%置信区间[CI]，2.25-2.67）和较大 BMI 下降（≥2.0；HR=4.65；95% CI，4.15-5.20）与较差的 OS 密切相关，而中度体重增加（0.5-2.0）降低了死亡风险（HR=0.78；95% CI，0.68-0.89），而较大体重增加（≥2.0）略微增加了死亡风险，但没有达到统计学意义（HR=1.10；95% CI，0.86-1.42）。MR 分析支持诊断后 BMI 变化在生存中的潜在因果作用。
本研究表明，诊断后 BMI 的变化与死亡风险相关。
我们的研究结果强化了诊断后 BMI 监测的重要性，表明体重减轻或体重增加较大可能是不必要的。
