Table 1 Baseline characteristics of the participants
From: Association of education level with the risk of female breast cancer: a prospective cohort study
Characteristics | Total cohort (n = 20,129) | Low EL (n = 1,078) | Medium EL (n = 16,833) | High EL (n = 2,218) | P |
|---|---|---|---|---|---|
Age(years, mean ± SD) | 48.75 + 11.50 | 58.51 + 8.26 | 49.38 + 10.72 | 39.29 + 12.51 | 0.000 |
BMI(kg/m2, mean ± SD) | 24.66 + 3.79 | 26.33 + 3.88 | 24.78 + 3.75 | 22.95 + 3.45 | 0.000 |
Smoking status, n(%) | |||||
Never | 19,662(97.68) | 961(89.15) | 16,502(98.03) | 2199(99.14) | 0.000 |
Former | 89(0.44) | 31(2.88) | 51(0.30) | 7(0.32) | |
Current | 378(1.88) | 86(7.98) | 280(1.66) | 12(0.54) | |
Alcohol consumption, n(%) | |||||
Never | 18,744(93.12) | 1018(94.43) | 15,919(94.57) | 1807(81.47) | 0.000 |
Former | 84(0.42) | 5(0.46) | 48(0.29) | 31(1.40) | |
Current | 1301(6.46) | 55(5.10) | 866(5.14) | 380(17.13) | |
Salt intake, n(%) | |||||
Light | 1888(9.38) | 164(15.21) | 1408(8.36) | 316(14.25) | 0.000 |
General | 16,882(83.87) | 791(73.38) | 14,406(85.58) | 1685(75.97) | |
Heavy | 1359(6.75) | 123(11.41) | 1019(6.05) | 217(9.78) | |
Physical activities, n(%) | |||||
Occasionally | 17,445(86.67) | 777(72.08) | 14,697(87.31) | 1971(88.86) | 0.000 |
Frequently | 2684(13.33) | 301(27.92) | 2136(12.69) | 247(11.14) | |
Hypertension, n(%) | |||||
No | 13,563(67.38) | 466(43.23) | 11,143(66.20) | 1954(88.10) | 0.000 |
Yes | 6566(32.62) | 612(56.77) | 5690(33.80) | 264(11.90) | |
Diabetes mellitus, n (%) | |||||
No | 18,503(91.92) | 899(83.40) | 15,445(91.75) | 2159(97.34) | 0.000 |
Yes | 1626(8.08) | 179(16.60) | 1388(8.25) | 59(2.66) | |