Univariable associations between explanatory variables and breast cancer
| Explanatory variable | Number of patients | Number with cancer (%) | Unadjusted odds ratio (95% CI) | P-value |
|---|---|---|---|---|
| Total number of patients | 802 | 59(7) | ||
| Age, years | ||||
| 25–39 | 272 | 3(1) | 1.0 | |
| 40–49 | 244 | 8(3) | 3.04(0.80 to 11.59) | 0.104 |
| 50–59 | 122 | 8(7) | 6.29(1.64 to 24.15) | 0.007 |
| 60–69 | 87 | 13(15) | 15.75(4.37 to 56.74) | <0.001 |
| 70–79 | 56 | 18(32) | 42.47(11.95 to 151.03) | <0.001 |
| ≥80 | 21 | 9(43) | 67.25(16.11 to 280.70) | <0.001 |
| Socioeconomic status (Carstairs category) | ||||
| 1 | 50 | 3(6) | 1.0 | |
| 2 | 127 | 15(12) | 2.10(0.58 to 7.59) | 0.259 |
| 3 | 168 | 13(8) | 1.31(0.36 to 4.81) | 0.680 |
| 4 | 68 | 3(4) | 0.72(0.14 to 3.74) | 0.699 |
| 5 | 56 | 8(14) | 2.61(0.65 to 10.44) | 0.175 |
| 6 | 116 | 5(4) | 0.71(0.16 to 3.07) | 0.642 |
| 7 | 54 | 4(7) | 1.25(0.27 to 5.90) | 0.775 |
| Unknown | 163 | 8(5) | 0.81(0.21 to 3.17) | 0.761 |
| Obesity classification | ||||
| Underweight | 11 | 1(9) | 1.0 | |
| Healthy weight | 319 | 18(6) | 0.60(0.07 to 4.93) | 0.633 |
| Overweight | 181 | 16(9) | 0.97(0.12 to 8.07) | 0.977 |
| Obese | 93 | 12(13) | 1.48(0.17 to 12.63) | 0.719 |
| Morbidly obese | 15 | 1(7) | 0.71(0.04 to 12.83) | 0.819 |
| Not recorded | 183 | 11(6) | 0.64(0.07 to 5.46) | 0.683 |
| Smoking history | ||||
| Current | 147 | 6(4) | 1.0 | |
| Previous | 43 | 4(9) | 2.41(0.65 to 8.97) | 0.189 |
| Never | 414 | 26(6) | 1.57(0.63 to 3.91) | 0.327 |
| Unknown | 198 | 23(12) | 3.09(1.22 to 7.79) | 0.017 |
| Menopausal status | ||||
| Premenopausal | 468 | 10(2) | 1.0 | |
| Perimenopausal | 269 | 46(17) | 9.45(4.68 to 19.07) | <0.001 |
| Postmenopausal | 45 | 2(4) | 2.13(0.45 to 10.04) | 0.339 |
| Unknown | 20 | 1(5) | 2.41(0.29 to 19.81) | 0.413 |
| Regular periods | 306 | 5(2) | 0.14(0.05 to 0.34) | <0.001 |
| Currently pregnant | 5 | 0(0) | n/a | |
| Contraception | ||||
| Oral contraceptive | 76 | 1(1) | 0.15(0.02 to 1.12) | 0.065 |
| Intra-uterine device | 36 | 2(6) | 0.73(0.17 to 3.12) | 0.673 |
| Hormone replacement therapy | ||||
| Current user | 24 | 3(13) | 1.84(0.53 to 6.36) | 0.334 |
| Past user | 114 | 9(8) | 1.09(0.52 to 2.29) | 0.812 |
| Ever user | 138 | 12(9) | 1.25(0.64 to 2.42) | 0.509 |
| Hysterectomy | 74 | 6(8) | 1.12(0.47 to 2.71) | 0.795 |
| Number of pregnancies | ||||
| 0 | 181 | 8(4) | 1.0 | |
| 1–3 | 490 | 36(7) | 1.71(0.78 to 3.76) | 0.179 |
| ≥4 | 131 | 15(11) | 2.80(1.15 to 6.81) | 0.023 |
| Past history | ||||
| Any breast problems | 306 | 13(4) | 0.43(0.23 to 0.82) | 0.010 |
| Previous clinic attendance | 373 | 16(4) | 0.40(0.22 to 0.73) | 0.003 |
| Breast cancer | 35 | 2(6) | 0.75(0.18 to 3.23) | 0.704 |
| Ductal carcinoma in situ | 3 | 0(0) | n/a | |
| Breast lump | 101 | 4(4) | 0.48(0.17 to 1.37) | 0.171 |
| Breast cyst/abscess | 108 | 5(5) | 0.58(0.22 to 1.47) | 0.249 |
| Breast pain | 21 | 0(0) | n/a | |
| Other breast problem | 40 | 2(5) | 0.65(0.15 to 2.77) | 0.561 |
| Signs after examination | ||||
| No signs | 147 | 2(1) | 1.0 | |
| Unilateral | 545 | 52(10) | 7.64(1.84 to 31.78) | 0.005 |
| Bilateral — same in each breast | 74 | 0(0) | n/a | |
| Bilateral — different between breasts | 36 | 5(14) | 11.69(2.17 to 63.06) | 0.004 |
| Discrete lump | 284 | 53(19) | 19.58(8.30 to 46.19) | 0.001 |
| Breast thickening | 66 | 8(12) | 1.85(0.84 to 4.09) | 0.127 |
| Abscess | 0 | 0(0) | n/a | |
| Breast pain | 180 | 0(0) | n/a | |
| Nipple discharge | 25 | 1(4) | 0.52(0.07 to 3.89) | 0.521 |
| Nipple retraction | 16 | 0(0) | n/a | |
| Nipple eczema | 1 | 1(100) | n/a | |
| Lymphadenopathy | 59 | 14(24) | 4.83(2.47 to 9.44) | <0.001 |
| Other (skin nodules, general nodularity) | 100 | 1(1) | 0.11(0.02 to 0.82) | 0.031 |
| Lump size | ||||
| >2 cm | 66 | 6(9) | 4.18(1.56 to 11.17) | 0.004 |
| ≥2 cm | 94 | 38(40) | 28.36(14.70 to 54.73) | <0.001 |
| Lump shape | ||||
| Vague thickening | 0 | 0(0) | n/a | |
| Round, oblong mass | 2 | 2(100) | ||
| Irregular | 1 | 0(0) | ||
| Lump mobility | ||||
| Mobile | 19 | 2(10) | 1.74(0.39 to 7.76) | 0.466 |
| Tethered to skin or chest wall | 8 | 8(100) | n/a | |
| Lump texture | ||||
| Smooth | 7 | 2(29) | 5.18(0.98 to 27.29) | 0.052 |
| Irregular | 0 | 0(0) | n/a | |
| Spongy | 0 | 0(0) | n/a | |
| Further details on nipple discharge | ||||
| Persistent | 2 | 0(0) | n/a | |
| Bloodstained | 4 | 0(0) | n/a | |
| Total number of signs | ||||
| 0 | 147 | 2(1) | 1.0 | |
| 1 | 583 | 39(7) | 5.20(1.24 to 21.78) | 0.024 |
| 2 | 68 | 15(22) | 20.52(4.54 to 92.75) | <0.001 |
| 3 | 4 | 3(75) | 217.50(15.23 to 3 105.68) | <0.001 |