Table 5.
History of hot flashes and the risk of breast cancer by histologic types
| Hot flashes | Controls (n=449) |
Ductal cases (n=494) |
Lobular cases (n=307) |
Ductal-lobular cases (n=187) |
|||
|---|---|---|---|---|---|---|---|
| n (%) | n (%) | OR‡ (95%CI) | n (%) | OR‡ (95%CI) | n (%) | OR‡ (95%CI) | |
| Never had menopausal symptoms | 51 (11.4) | 96 (19.4) | 1.0 (ref) | 56 (18.2) | 1.0 (ref) | 25 (13.4) | 1.0 (ref) |
| Experienced menopausal symptoms, but never hot flashes | 55 (12.2) | 61 (12.3) | 0.5 (0.3–0.9)† | 45 (14.7) | 0.7 (0.4–1.2) | 27 (14.4) | 0.9 (0.4–2.0) |
| Ever experienced hot flashes* | 343 (76.4) | 337 (68.2) | 0.5 (0.3–0.7)† | 206 (67.1) | 0.5 (0.3–0.7)† | 135 (72.2) | 0.7 (0.4–1.2) |
| Ever had hot flashes without perspiration or awakening | 39 (100) | 51 (100) | 0.6 (0.3–1.1) | 36 (100) | 0.8 (0.4–1.5) | 31 (100) | 1.5 (0.7–3.2) |
| Duration of hot flashes without perspiration or awakening (months)§ | |||||||
| <12 | 17 (43.6) | 21 (41.2) | 0.5 (0.2–1.1) | 15 (41.7) | 0.6 (0.3–1.6) | 10 (32.3) | 1.0 (0.3–3.0) |
| ≥12 | 22 (56.4) | 30 (58.8) | 0.7 (0.3–1.3) | 21 (58.3) | 0.9 (0.4–2.0) | 21 (67.7) | 1.8 (0.7–4.2) |
| Ever had hot flashes with perspiration, but not awakening | 132 (100) | 147 (100) | 0.5 (0.3–0.8)† | 72 (100) | 0.4 (0.3–0.7)† | 56 (100) | 0.7 (0.3–1.3) |
| Duration of hot flashes with perspiration but not awakening (months)§ | |||||||
| <12 | 48 (36.4) | 57 (38.8) | 0.6 (0.3–1.0)† | 29 (40.3) | 0.4 (0.2–0.8)† | 20 (35.7) | 0.6 (0.3–1.3) |
| 12–35 | 43 (32.6) | 48 (32.6) | 0.5 (0.3–0.9)† | 21 (29.2) | 0.4 (0.2–0.8)† | 18 (32.2) | 0.6 (0.3–1.4) |
| ≥36 | 41 (31.0) | 42 (28.6) | 0.5 (0.3–0.9)† | 22 (30.5) | 0.5 (0.3–1.0)† | 18 (32.1) | 0.8 (0.3–1.8) |
| Ever had hot flashes with awakening | 147 (100) | 114 (100) | 0.4 (0.2–0.6)† | 79 (100) | 0.3 (0.2–0.6)† | 40 (100) | 0.5 (0.3–1.1) |
| Duration of hot flashes with awakening (months)§ | |||||||
| <12 | 34 (23.1) | 36 (31.6) | 0.5 (0.3–0.9)† | 25 (31.6) | 0.5 (0.2–1.0)† | 13 (32.5) | 0.8 (0.3–2.1) |
| 12–35 | 56 (38.1) | 32 (28.1) | 0.3 (0.2–0.5)† | 22 (27.8) | 0.2 (0.1–0.5)† | 15 (37.5) | 0.5 (0.2–1.2) |
| ≥36 | 57 (38.8) | 46 (40.3) | 0.4 (0.2–0.6)† | 32 (40.6) | 0.3 (0.2–0.7)† | 12 (30.0) | 0.4 (0.2–1.0) |
| P for trend in hot flash intensity¶ | 0.007 | 0.017 | <0.001 | ||||
*
25 controls, 25 IDC, 19 ILC, and 8 IDLC cases who experienced hot flashes had missing data on the intensity of hot flashes.
†
p-value <0.05.
‡
Odds ratios (OR) are adjusted for age, year, duration of hormone therapy use, and the type of menopause.
§
All p-values for trend in duration of hot flashes were >0.05.
¶
p-value for trend across the three categories of hot flash intensity.