Table 2 Multivariatea comparisons of personal and family health history, socioeconomic, and other characteristics of women with breast cancer and controls in Marin County, California, 1997–99
From: Risk factors for breast cancer in a population with high incidence rates
All women | Women aged 50 years and over | Women under 50 years of age | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
Variable | (Total N)a | Cases N (%)(285) | Controls N (%)(286) | Multivariate OR (95% CI) | Cases N (%)(201) | Controls N (%)(201) | Multivariate OR (95% CI) | Cases N (%)(84) | Controls N (%)(85) | Multivariate OR (95% CI) |
Personal and family health history | ||||||||||
First-degree relative with breast cancer | ||||||||||
No | 231 (81.1) | 230 (80.4) | 1.0 | 162 (80.6) | 157 (78.1) | 1.0 | 69 (82.1) | 73 (85.9) | 1.0 | |
Yes | 54 (18.9) | 56 (19.6) | 0.95 (0.58–1.5) | 39 (19.4) | 44 (21.9) | 0.84 (0.47–1.5) | 15 (17.9) | 12 (14.1) | 1.3 (0.40–4.0) | |
Benign biopsy history | ||||||||||
None | 196 (68.8) | 213 (74.5) | 1.0 | 128 (63.7) | 145 (72.1) | 1.0 | 68 (81.0) | 68 (80.0) | 1.0 | |
Fine-needle aspiration only | 16 (5.6) | 19 (6.6) | 0.74 (0.34–1.6) | 14 (7.0) | 10 (5.0) | 1.4 (0.48–3.8) | 2 (2.4) | 9 (10.6) | 0.13 (0.02–0.98) | |
Surgical biopsyb | 73 (25.6) | 54 (18.9) | 1.1 (0.66–1.7) | 59 (29.4) | 46 (22.9) | 0.97 (0.56–1.7) | 14 (16.7) | 8 (9.4) | 0.78 (0.22–2.9) | |
Previous radiation treatment | ||||||||||
No | 252 (88.4) | 266 (93.0) | 1.0 | 174 (86.6) | 185 (92.0) | 1.0 | 78 (92.9) | 81 (95.3) | 1.0 | |
Yes | 33 (11.6) | 20 (7.0) | 1.7 (0.89–3.3) | 27 (13.4) | 16 (8.0) | 1.6 (0.76–3.5) | 6 (7.1) | 4 (4.7) | 6.1 (1.1–34.9) | |
Age at menarche | ||||||||||
15 or more years old | 18 (6.3) | 26 (9.1) | 1.0 | 14 (7.0) | 18 (9.0) | 1.0 | 4 (4.8) | 8 (9.4) | 1.0 | |
12–14 years old | 220 (77.2) | 197 (68.9) | 1.5 (0.74–3.1) | 152 (75.6) | 132 (65.7) | 1.3 (0.52–3.1) | 68 (81.0) | 65 (76.5) | 2.6 (0.53–12.5) | |
11 or less years old | 47 (16.5) | 63 (22.0) | 1.2 (0.51–2.6) | 35 (17.4) | 51 (25.4) | 0.74 (0.27–2.0) | 12 (14.3) | 12 (14.1) | 2.5 (0.37–16.5) | |
Menopause status | ||||||||||
Premenopausal | 81 (28.4) | 66 (23.1) | 1.0 | 13 (6.5) | 7 (3.5) | 1.0 | 68 (81.0) | 59 (69.4) | 1.0 | |
Perimenopausal | 29 (10.2) | 31 (10.8) | 0.52 (0.26–1.0) | 19 (9.5) | 13 (6.5) | 0.76 (0.19–3.0) | 10 (11.9) | 18 (21.2) | 0.17 (0.05–0.59) | |
Postmenopausal | 175 (61.4) | 189 (66.1) | 0.40 (0.19–0.84) | 169 (84.1) | 181 (90.0) | 0.45 (0.14–1.5) | 6 (7.1) | 8 (9.4) | 0.38 (0.06–2.3) | |
Reproductive history | ||||||||||
Never pregnant | 45 (15.8) | 51 (17.8) | 1.0 | 23 (11.4) | 38 (18.9) | 1.0 | 22 (26.2) | 13 (15.3) | 1.0 | |
Pregnant, no birth | 27 (9.5) | 23 (8.0) | 1.4 (0.65–3.0) | 15 (7.5) | 11 (5.5) | 2.2 (0.75–6.3) | 12 (14.3) | 12 (14.1) | 0.52 (0.12–2.4) | |
Birth, did not breastfeed | 57 (20.0) | 33 (11.5) | 1.9 (0.97–3.9) | 53 (26.4) | 30 (14.9) | 2.6 (1.1–5.8) | 4 (4.8) | 3 (3.5) | 1.9 (0.22–16.0) | |
Breastfed | 156 (54.7) | 179 (62.6) | 0.98 (0.58–1.7) | 110 (54.7) | 122 (60.7) | 1.4 (0.68–2.7) | 46 (54.8) | 57 (67.1) | 0.35 (0.11–1.1) | |
Reproductive history, recategorization of those who had given birth versus never pregnant a | ||||||||||
One birth | 53 (18.6) | 55 (19.2) | 1.0 (0.54–2.0) | 36 (17.9) | 33 (16.4) | 1.4 (0.62–3.4) | 17 (20.2) | 22 (25.9) | 0.36 (0.09–1.4) | |
Two births | 86 (30.2) | 88 (30.8) | 1.1 (0.59–1.9) | 61 (30.3) | 60 (29.9) | 1.4 (0.66–3.0) | 25 (29.8) | 28 (32.9) | 0.51 (0.15–1.8) | |
Three or more births | 74 (26.0) | 69 (24.1) | 1.3 (0.68–2.4) | 66 (32.8) | 59 (29.4) | 1.9 (0.89–4.1) | 8 (9.5) | 10 (11.8) | 0.18 (0.04–0.90) | |
Reproductive history, recategorization of those who had breastfed versus never pregnant a | ||||||||||
Breastfed 6 months or less | 62 (21.8) | 71 (24.8) | 0.87 (0.47–1.6) | 50 (24.9) | 54 (26.9) | 1.2 (0.57–2.7) | 12 (14.3) | 17 (20.0) | 0.40 (0.1–1.7) | |
Breastfed 7–12 months | 41 (14.4) | 42 (14.7) | 1.3 (0.65–2.6) | 26 (12.9) | 29 (14.4) | 1.6 (0.65–3.8) | 15 (17.9) | 13 (15.3) | 0.54 (0.14–2.1) | |
Breastfed more than 12 months | 53 (18.6) | 66 (23.1) | 0.92 (0.49–1.7) | 34 (16.9) | 39 (19.4) | 1.4 (0.61–3.3) | 19 (22.6) | 27 (31.8) | 0.22 (0.06–0.83) | |
Oral contraceptive use | ||||||||||
Never | 68 (23.9) | 42 (14.7) | 1.0 | 55 (27.4) | 37 (18.4) | 1.0 | 13 (15.5) | 5 (5.9) | 1.0 | |
Ever | 217 (76.1) | 244 (85.3) | 0.43 (0.26–0.72) | 146 (72.6) | 164 (81.6) | 0.41 (0.22–0.75) | 71 (84.5) | 80 (94.1) | 0.15 (0.03–0.65) | |
Hormone replacement therapy (HRT) | ||||||||||
None | 129 (45.3) | 126 (44.1) | 1.0 | 58 (28.9) | 60 (29.9) | 1.0 | 71 (84.5) | 66 (77.6) | 1.0 | |
Combination therapy | 101 (35.4) | 103 (36.0) | 0.93 (0.55–1.6) | 96 (47.8) | 94 (46.8) | 0.99 (0.54–1.8) | 5 (6.0) | 9 (10.6) | 0.47 (0.08–2.7) | |
Other HRTc | 55 (19.3) | 57 (19.9) | 0.96 (0.55–1.7) | 47 (23.4) | 47 (23.4) | 1.1 (0.54–2.1) | 8 (9.5) | 10 (11.8) | 0.75 (0.17–3.4) | |
Highest body mass index (BMI) after age 21 daysd | ||||||||||
BMI < 25 | 184 (64.6) | 141 (49.3) | 1.0 | 124 (61.7) | 89 (44.3) | 1.0 | 60 (71.4) | 52 (61.2) | 1.0 | |
25 ≤ BMI < 30 | 66 (23.2) | 84 (29.4) | 0.53 (0.34–0.84) | 49 (24.4) | 62 (30.8) | 0.47 (0.27–0.83) | 17 (20.2) | 22 (25.9) | 0.52 (0.19–1.4) | |
BMI ≥ 30 | 35 (12.3) | 61 (21.3) | 0.38 (0.22–0.66) | 28 (13.9) | 50 (24.9) | 0.29 (0.15–0.57) | 7 (8.3) | 11 (12.9) | 0.30 (0.08–1.2) | |
P for trende | 0.0003 | 0.0008 | 0.05 | |||||||
Number of mammograms, 1990–94 | ||||||||||
Less than four | 98 (34.4) | 145 (50.7) | 1.0 | 36 (17.9) | 73 (36.3) | 1.0 | 62 (73.8) | 72 (84.7) | 1.0 | |
Four or more | 187 (65.6) | 141 (49.3) | 2.5 (1.6–4.0) | 165 (82.1) | 128 (63.7) | 2.6 (1.5–4.6) | 22 (26.2) | 13 (15.3) | 2.1 (0.67–6.4) | |
Socioeconomic status | ||||||||||
Socioeconomic status before age 21 | ||||||||||
Poor/working class | 49 (17.2) | 58 (20.3) | 1.0 | 34 (16.9) | 51 (25.4) | 1.0 | 15 (17.9) | 7 (8.2) | 1.0 | |
Lower middle class | 44 (15.4) | 31 (10.8) | 1.7 (0.86–3.5) | 31 (15.4) | 26 (12.9) | 1.9 (0.84–4.5) | 13 (15.5) | 5 (5.9) | 1.2 (0.16–8.6) | |
Middle class | 113 (39.6) | 132 (46.2) | 1.0 (0.58–1.7) | 81 (40.3) | 85 (42.3) | 1.5 (0.80–2.9) | 32 (38.1) | 47 (55.3) | 0.30 (0.07–1.3) | |
Upper middle/upper class | 79 (27.7) | 65 (22.7) | 1.3 (0.73–2.4) | 55 (27.4) | 39 (19.4) | 2.2 (1.0–4.6) | 24 (28.6) | 26 (30.6) | 0.23 (0.05–1.1) | |
Separating upper middle and upper versus poor/working class a | ||||||||||
Upper middle class | 68 (23.9) | 63 (22.0) | 1.1 (0.57–2.0) | 46 (22.9) | 38 (18.9) | 1.6 (0.73–3.4) | 22 (26.2) | 25 (29.4) | 0.22 (0.05–1.1) | |
Upper class | 11 (3.9) | 2 (0.7) | 9.7 (1.9–49.0) | 9 (4.5) | 1 (0.5) | 31.5 (3.3–298.6) | 2 (2.4) | 1 (1.2) | 1.6 (0.03–82.1) | |
Highest degree obtained | ||||||||||
High school (HS) | 69 (24.2) | 66 (23.1) | 1.0 | 55 (27.4) | 55 (27.4) | 1.0 | 14 (16.7) | 11 (12.9) | 1.0 | |
Some college or other post-HS | 59 (20.7) | 66 (23.1) | 0.83 (0.47–1.4) | 37 (18.4) | 47 (23.4) | 0.63 (0.32–1.3) | 22 (26.2) | 19 (22.4) | 1.2 (0.32–4.9) | |
Bachelor's | 105 (36.8) | 103 (36.0) | 0.99 (0.59–1.7) | 71 (35.3) | 64 (31.8) | 1.1 (0.59–2.1) | 34 (40.5) | 39 (45.9) | 0.73 (0.19–2.8) | |
Graduate | 52 (18.2) | 51 (17.8) | 0.93 (0.50–1.7) | 38 (18.9) | 35 (17.4) | 0.89 (0.42–1.9) | 14 (16.7) | 16 (18.8) | 0.80 (0.17–3.8) | |
Religion in which raised | ||||||||||
Protestant | 128 (44.9) | 111 (38.8) | 1.0 | 100 (49.8) | 84 (41.8) | 1.0 | 28 (33.3) | 27 (31.8) | 1.0 | |
Catholic | 104 (36.5) | 114 (39.9) | 0.72 (0.47–1.1) | 70 (34.8) | 78 (38.8) | 0.68 (0.40–1.1) | 34 (40.5) | 36 (42.4) | 0.53 (0.20–1.4) | |
Jewish | 23 (8.1) | 18 (6.3) | 1.2 (0.56–2.6) | 16 (8.0) | 11 (5.5) | 1.6 (0.57–4.3) | 7 (8.3) | 7 (8.2) | 0.95 (0.18–4.9) | |
Other | 18 (6.3) | 18 (6.3) | 0.94 (0.42–2.1) | 7 (3.5) | 14 (7.0) | 0.33 (0.11–1.0) | 11 (13.1) | 4 (4.7) | 3.2 (0.60–16.7) | |
None | 12 (4.2) | 25 (8.7) | 0.39 (0.17–0.91) | 8 (4.0) | 14 (7.0) | 0.53 (0.18–1.6) | 4 (4.8) | 11 (12.9) | 0.20 (0.03–1.1) | |
Alcohol and tobacco use | ||||||||||
Age began drinking alcohol | ||||||||||
Before age 21 years | 228 (80.0) | 255 (89.2) | 1.0 | 156 (77.6) | 176 (87.6) | 1.0 | 72 (85.7) | 79 (92.9) | 1.0 | |
After age 21 years | 57 (20.0) | 31 (10.8) | 2.8 (1.6–5.0) | 45 (22.4) | 25 (12.4) | 3.0 (1.5–5.9) | 12 (14.3) | 6 (7.1) | 2.9 (0.60–14.2) | |
Average drinks after age 21f | ||||||||||
<1 drink per week | 81 (28.4) | 104 (36.4) | 1.0 | 56 (27.9) | 68 (33.8) | 1.0 | 25 (29.8) | 36 (42.4) | 1.0 | |
≥ 1 drinks per week, <2 per day | 137 (48.1) | 149 (52.1) | 1.1 (0.72–1.8) | 90 (44.8) | 106 (52.7) | 0.63 (0.36–1.1) | 47 (56.0) | 43 (50.6) | 3.5 (1.2–10.1) | |
~2 drinks per day | 52 (18.2) | 27 (9.4) | 2.3 (1.2–4.4) | 42 (20.9) | 22 (10.9) | 1.5 (0.70–3.3) | 10 (11.9) | 5 (5.9) | 3.6 (0.79–16.5)f | |
≥ 3 drinks per day | 15 (5.3) | 6 (2.1) | 3.6 (1.2–11.5) | 13 (6.5) | 5 (2.5) | 2.9 (0.80–10.9) | 2 (2.4) | 1 (1.2) | ||
P for trende | 0.004 | 0.090 | 0.030 | |||||||
Lifetime pack-years of cigarette smoking | ||||||||||
None | 117 (41.1) | 130 (45.5) | 1.0 | 74 (36.8) | 87 (43.3) | 1.0 | 43 (51.2) | 43 (50.6) | 1.0 | |
Duration ≤ 8.25 years | 39 (13.7) | 38 (13.3) | 1.3 (0.70–2.2) | 24 (11.9) | 24 (11.9) | 1.3 (0.61–2.9) | 15 (17.9) | 14 (16.5) | 2.3 (0.72–7.4) | |
> 8.25 years to ≤ 15 years duration | 29 (10.2) | 42 (14.7) | 0.81 (0.44–1.5) | 21 (10.4) | 28 (13.9) | 0.99 (0.45–2.2) | 8 (9.5) | 14 (16.5) | 0.38 (0.11–1.3) | |
>15 years to ≤ 28.5 years duration | 36 (12.6) | 37 (12.9) | 1.1 (0.61–2.0) | 22 (10.9) | 26 (12.9) | 1.0 (0.47–2.3) | 14 (16.7) | 11 (12.9) | 1.1 (0.34–3.8) | |
Duration > 28.5 years | 64 (22.5) | 39 (13.6) | 2.4 (1.3–4.2) | 60 (29.9) | 36 (17.9) | 3.1 (1.6–5.9) | 4 (4.8) | 3 (3.5) | 2.0 (0.18–21.2) | |
P for trende | 0.02 | 0.004 | 0.78 | |||||||