Table 1 Baseline characteristics of study cohort according to tertiles of serum 25(OH)D (n = 1,295)
Serum 25(OH)D | |||
|---|---|---|---|
Characteristic | < 35 nmol/L | 35-55 nmol/L | ≥ 55 nmol/L |
Number of patients | 432 | 407 | 456 |
Age at diagnosis (years), mean ± SD | 64.0 ± 5.7 | 63.7 ± 5.4 | 62.5 ± 5.4 |
25(OH)D concentration (nmol/L), median | 25.7 | 44.4 | 71.3 |
Follow-up time (years), median | 5.6 | 5.9 | 6.0 |
Time between diagnosis and blood collection (days), median | 82 | 63 | 130 |
BMI at recruitment (kg/m2), mean ± SD | 27.7 ± 4.9 | 26.6 ± 4.4 | 25.5 ± 4.1 |
Leisure time physical activity since age 50 (met-hr/wk), mean ± SD | 37.3 ± 30.0 | 43.5 ± 33.0 | 49.5 ± 36.4 |
Season of blood draw, % | |||
Jan-Mar | 37.5 | 16.7 | 13.6 |
Apr-Jun | 22.0 | 24.8 | 16.0 |
Jul-Sept | 13.0 | 29.5 | 43.6 |
Oct-Dec | 27.5 | 29.0 | 26.8 |
Tumor size, % | |||
In situ | 3.9 | 4.9 | 8.3 |
≤ 2 cm | 44.4 | 51.8 | 51.1 |
> 2- ≤ 5 cm | 32.9 | 32.4 | 32.2 |
> 5 cm | 5.6 | 2.2 | 2.6 |
Growth into chest wall/skin | 5.6 | 2.0 | 1.6 |
Neoadjuvant CT | 7.4 | 6.1 | 4.2 |
Missing | 0.2 | 0.5 | 0.0 |
Nodal status, %* | |||
0 | 54.4 | 58.2 | 59.6 |
1-3 | 19.2 | 19.7 | 19.7 |
4-9 | 6.7 | 6.6 | 4.0 |
≥ 10 | 7.6 | 3.7 | 4.2 |
Missing | 0.7 | 0.7 | 0.0 |
Metastases, % | |||
In situ | 3.9 | 4.9 | 8.3 |
No | 89.1 | 89.7 | 88.8 |
Yes | 5.6 | 4.9 | 2.2 |
Missing | 1.4 | 0.5 | 0.7 |
Tumor grade, %* | |||
Low + moderate | 61.1 | 65.1 | 64.5 |
High | 27.3 | 23.3 | 22.8 |
Missing | 0.2 | 0.5 | 0.2 |
ERPR, %* | |||
ER+PR+ | 55.3 | 55.0 | 50.9 |
ER+PR-/ER-PR+ | 19.2 | 15.7 | 20.8 |
ER-PR- | 14.1 | 17.4 | 15.8 |
Missing | 0.0 | 0.7 | 0.0 |
Chemotherapy, % | |||
No | 49.1 | 52.1 | 58.8 |
Yes | 48.8 | 47.6 | 41.0 |
Missing | 2.1 | 0.3 | 0.2 |
Radiotherapy, % | |||
No | 27.8 | 17.9 | 25.4 |
Yes | 72.0 | 82.1 | 74.4 |
Missing | 0.2 | 0.0 | 0.2 |
Tamoxifen/aromatase inhibitor use, % | |||
No | 14.8 | 18.9 | 19.3 |
Yes | 79.9 | 77.2 | 76.3 |
Missing | 5.3 | 3.9 | 4.4 |
Hormone replacement therapy, % | |||
No | 71.1 | 57.7 | 48.9 |
Yes | 27.8 | 41.5 | 50.0 |
Missing | 1.1 | 0.7 | 1.1 |
Diabetes, % | |||
No | 87.0 | 89.7 | 91.9 |
Yes | 13.0 | 10.3 | 7.9 |
Missing | 0.0 | 0.0 | 0.2 |
Cardiovascular disease, % | |||
No | 41.0 | 48.2 | 51.8 |
Yes | 59.0 | 51.8 | 48.2 |
Mode of detection, % | |||
Self-detected by palpation/secretion/pain | 65.3 | 56.3 | 53.5 |
Physician-detected by routine investigation/mammography/ultrasound | 34.5 | 43.5 | 45.4 |
Missing | 0.2 | 0.2 | 1.1 |