Body mass index increases the lymph node metastasis risk of breast cancer: a dose-response meta-analysis with 52904 subjects from 20 cohort studies

Table 3 The results of linear dose-response analysis between body mass index (BMI) and lymph node metastasis of breast cancer

Variables	Number of cases	Test of heterogeneity	Model	Regression model test	RR (95%CI)
All	52904	χ 2=30.34, P=0.048	RE	χ 2=29.30, P<0.001	1.0089 (1.0057, 1.0122)
Area
Asia	8854	χ 2=4.71, P=0.095	FE	χ 2=11.13, P=0.001	1.0099 (1.0041, 1.0157)
Europe	28979	χ 2=13.70, P=0.057	FE	χ 2=36.31, P<0.001	1.0085 (1.0057, 1.0113)
America	8701	χ 2=5.16, P=0.641	FE	χ 2=6.01, P=0.014	1.0061 (1.0012, 1.0110)
Menopausal
Pre	8994	χ 2=10.53, P=0.032	RE	χ 2=5.61, P=0.018	1.0144 (1.0025, 1.0264)
Post	12456	χ 2=2.57, P=0.766	FE	χ 2=23.48, P<0.001	1.0145 (1.0086, 1.0204)
Study period
≤ 5y	4901	χ 2=3.66, P=0.600	FE	χ 2=19.94, P<0.001	1.0222 (1.0124, 1.0321)
> 5y	48003	χ 2=16.61, P=0.218	FE	χ 2=40.88, P<0.001	1.0061 (1.0042, 1.0080)

ISSN: 1471-2407