Table 3.

Subgroup analysis of the association between EL and breast cancer risk

Variable	EL	B	SE	WALD	P	HR(95%CI)
Age (years)
< 50	medium	0.023	0.716	0.001	0.974	1.02(0.25–4.17)
	high	0.357	0.762	0.219	0.640	1.43(0.32–6.37)
≥ 50	medium	0.968	0.421	5.288	0.022	2.63(1.15–6.01)
	high	1.344	0.534	6.348	0.012	3.84(1.35–10.92)
BMI(kg/m2)
< 28	medium	0.736	0.421	3.057	0.080	2.08(0.92–4.76)
	high	0.716	0.478	2.248	0.134	2.05(0.80–5.22)
≥ 28	medium	1.037	0.725	2.045	0.153	2.82(0.68–11.69)
	high	1.808	0.848	4.549	0.033	6.10(1.16–32.11)
Physical activities
Occasionally	medium	0.850	0.418	4.133	0.042	2.34(1.03–5.31)
	high	0.995	0.470	4.474	0.034	2.70(1.08–6.80)
Frequently	medium	0.800	0.740	1.169	0.280	2.23(0.52–9.49)
	high	0.571	1.019	0.314	0.575	1.77(0.24–13.04)
Hypertension
No	medium	0.841	0.587	2.052	0.152	2.32(0.73–7.32)
	high	0.807	0.637	1.605	0.205	2.24(0.64–7.82)
Yes	medium	0.779	0.465	2.806	0.094	2.18(0.88–5.43)
	high	1.385	0.577	5.758	0.016	3.99(1.29–12.39)

EL Education level

Compared with the low El group respectively

Adjusted for age, smoking status, alcohol consumption, BMI, physical activity, salt intake, hypertension, and diabetes mellitus