Table 1 Comparison of cases and controls on demographics and selected breast cancer risk factors
Premenopausal women | Postmenopausal women | All women | |||||||
|---|---|---|---|---|---|---|---|---|---|
n = 239 | n = 248 | ||||||||
Cases (61) mean value (SD) | Controls (178) mean value (SD) | P value | Cases (132) mean value (SD) | Controls (116) mean value (SD) | P value | Cases (193) mean value (SD) | Controls (294) mean value (SD) | P value | |
Age at enrollment (years) | 45.1 (5.3) | 41.8 (6.1) | <0.01 | 61.4 (10.4) | 63.4 (10.2) | 0.2 | 56.2 (11.8) | 50.4 (13.2) | <0.01 |
Age at menarche (years) | 14.0 (1.6) | 13.9 (1.4) | 0.7 | 14.1 (1.6) | 14.1 (1.9) | 0.7 | 14.1 (1.6) | 14.0 (1.6) | 0.8 |
Age at first birth (years) | 24.4 (4.5) | 24.2 (4.1) | 1.0 | 24.7 (4.3) | 24.6 (4.5) | 0.7 | 24.6 (4.4) | 24.3 (4.2) | 0.6 |
Age at last birth (years) | 29.3 (7.1) | 27.7 (1.9) | 0.7 | 30.5 (5.5) | 29.5 (5.1) | 0.3 | 30.1 (6.1) | 28.2 (4.9) | <0.01 |
Number of parity | 1.9 (1.3) | 1.5 (0.9) | 0.7 | 2.1 (1.4) | 1.5 (1.3) | <0.01 | 2.0 (1.4) | 1.5 (1.1) | <0.01 |
Family history of breast cancer in first-degree relatives | 10 | 49 | 0.07 | 16 | 34 | <0.01 | 26 | 83 | <0.01 |
Education | 0.29 | 0.13 | <0.01 | ||||||
Primary | 15 | 33 | 57 | 34 | 72 | 67 | |||
Vocational | 7 | 31 | 5 | 8 | 12 | 39 | |||
Secondary | 21 | 47 | 49 | 48 | 70 | 94 | |||
Higher | 18 | 67 | 21 | 25 | 39 | 92 | |||
Number of miscarriages | 1.0 (3.7) | 0.3 (0.7) | 0.1 | 0.6 (1.0) | 0.5 (0.8) | 0.4 | 0.7 (2.2) | 0.4 (0.7) | <0.01 |
Age at menopause (years) | – | – | – | 48.7 (5.2) | 49.5 (4.7) | 0.8 | 48.7 (5.2) | 49.5 (4.7) | 0.8 |