Pan Kathy, Larson Joseph C, Prentice Ross L, Mortimer Joanne E, Neuhouser Marian L, Manson JoAnn E, Van Horn Linda, Rohan Thomas E, Lane Dorothy, Chlebowski Rowan T
Lundquist Institute for Biomedical Innovation at Harbor, UCLA Medical Center, Torrance, CA, USA.
Fred Hutchinson Cancer Research Center, Seattle, WA, USA.
JNCI Cancer Spectr. 2020 Nov 7;4(6):pkaa101. doi: 10.1093/jncics/pkaa101. eCollection 2020 Dec.
Prior studies of dietary protein intake and breast cancer have been mixed and were limited by dietary self-report measurement error.
Biomarker-calibrated total protein intake and estimated vegetable protein and animal protein intake were determined from baseline food frequency questionnaires in 100 024 Women's Health Initiative participants. Associations between total, animal, and vegetable protein intake and breast cancer incidence, deaths from breast cancer, and deaths after breast cancer were estimated using Cox proportional hazards regression. Breast cancers were verified by medical record review and survival outcomes enhanced by National Death Index queries. All statistical tests were 2-sided.
After 14 years of follow-up, there were 6340 incident breast cancers, 764 deaths from breast cancer, and 2059 deaths after breast cancer. In multivariable analyses, higher calibrated total protein intake was not associated with breast cancer incidence or deaths from or after breast cancer. Vegetable protein intake was associated with statistically significantly lower breast cancer incidence (hazard ratio [HR] = 0.98, 95% confidence interval [CI] = 0.96 to 0.99, = .006) and statistically significantly lower risk of death after breast cancer (HR = 0.93, 95% CI = 0.91 to 0.97 < .001) but not with deaths from breast cancer. In contrast, higher animal protein intake was associated with statistically significantly higher breast cancer incidence (HR = 1.03, 95% CI = 1.01 to 1.06, = .02) but not with deaths from or after breast cancer.
Calibrated total protein intake was not associated with breast cancer incidence or mortality. Higher vegetable protein intake was associated with lower breast cancer incidence and lower risk of death after breast cancer. Higher animal protein intake was associated with higher breast cancer incidence.
先前关于膳食蛋白质摄入量与乳腺癌的研究结果不一，且受膳食自我报告测量误差的限制。
从100024名女性健康倡议参与者的基线食物频率问卷中确定经生物标志物校准的总蛋白质摄入量以及估计的植物蛋白和动物蛋白摄入量。使用Cox比例风险回归估计总蛋白、动物蛋白和植物蛋白摄入量与乳腺癌发病率、乳腺癌死亡以及乳腺癌后死亡之间的关联。通过病历审查核实乳腺癌情况，并通过国家死亡指数查询提高生存结局的准确性。所有统计检验均为双侧检验。
经过14年的随访，有6340例新发乳腺癌、764例乳腺癌死亡以及2059例乳腺癌后死亡。在多变量分析中，经校准的总蛋白摄入量较高与乳腺癌发病率、乳腺癌死亡或乳腺癌后死亡均无关联。植物蛋白摄入量与乳腺癌发病率在统计学上显著降低相关（风险比[HR]=0.98，95%置信区间[CI]=0.96至0.99，P=.006），且与乳腺癌后死亡风险在统计学上显著降低相关（HR=0.93，95%CI=0.91至0.97，P<.001），但与乳腺癌死亡无关。相比之下，动物蛋白摄入量较高与乳腺癌发病率在统计学上显著升高相关（HR=1.03，95%CI=1.01至1.06，P=.02），但与乳腺癌死亡或乳腺癌后死亡无关。
经校准的总蛋白摄入量与乳腺癌发病率或死亡率无关。较高的植物蛋白摄入量与较低的乳腺癌发病率和较低的乳腺癌后死亡风险相关。较高的动物蛋白摄入量与较高的乳腺癌发病率相关。
