Table 1.
Baseline Characteristics of Randomly Assigned Participants
| Characteristic | All (n = 439) |
Control(n = 87) |
Diet (n = 118) |
Exercise(n = 117) |
Diet + Exercise(n = 117) |
|||||
|---|---|---|---|---|---|---|---|---|---|---|
| No. | % | No. | % | No. | % | No. | % | No. | % | |
| Age, years | ||||||||||
| Mean | 58.0 | 57.4 | 58.1 | 58.1 | 58.0 | |||||
| SD | 5.0 | 4.4 | 6.0 | 5.0 | 4.5 | |||||
| Range | 50-76 | 51-70 | 50-76 | 51-72 | 51-73 | |||||
| Weight, kg | ||||||||||
| Mean | 83.6 | 84.2 | 84.0 | 83.7 | 82.5 | |||||
| SD | 11.8 | 12.5 | 11.8 | 12.3 | 10.8 | |||||
| BMI, kg/m2 | ||||||||||
| Mean | 30.9 | 30.7 | 31.1 | 30.7 | 31.0 | |||||
| SD | 4.0 | 3.9 | 3.9 | 3.7 | 4.3 | |||||
| Body fat, % | ||||||||||
| Mean | 47.2 | 47.3 | 47.0 | 47.3 | 47.4 | |||||
| SD | 4.3 | 4.4 | 4.3 | 4.1 | 4.5 | |||||
| Body fat mass, kg | ||||||||||
| Mean | 39.8 | 40.1 | 39.8 | 39.9 | 39.4 | |||||
| SD | 8.1 | 8.5 | 8.1 | 8.2 | 7.9 | |||||
| Lean mass, % | ||||||||||
| Mean | 48.5 | 48.5 | 48.7 | 48.3 | 48.3 | |||||
| SD | 4.2 | 4.3 | 4.3 | 3.9 | 4.4 | |||||
| Lean mass, kg | ||||||||||
| Mean | 40.2 | 40.6 | 40.7 | 40.2 | 39.6 | |||||
| SD | 5.0 | 5.3 | 5.1 | 5.3 | 4.3 | |||||
| VO2max, L/min | ||||||||||
| Mean | 1.90 | 1.93 | 1.89 | 1.85 | 1.93 | |||||
| SD | 0.33 | 0.37 | 0.31 | 0.31 | 0.34 | |||||
| Usual physical activity, MET min/wk | ||||||||||
| Mean | 151 | 109 | 160 | 173 | 151 | |||||
| SD | 208 | 196 | 230 | 202 | 197 | |||||
| Total calories, kcal/d* | ||||||||||
| Mean | 1,934 | 1,988 | 1,884 | 1,986 | 1,890 | |||||
| SD | 638 | 669 | 661 | 589 | 638 | |||||
| Alcohol, g/d* | ||||||||||
| Mean | 7.3 | 8.2 | 8.8 | 7.1 | 5.4 | |||||
| SD | 10.8 | 11.5 | 13.9 | 9.7 | 69 | |||||
| Ethnicity | ||||||||||
| Non-Hispanic white | 373 | 85.0 | 74 | 85.1 | 101 | 85.6 | 98 | 83.8 | 100 | 85.4 |
| African American | 35 | 8.0 | 6 | 6.9 | 9 | 7.6 | 15 | 12.8 | 5 | 4.3 |
| Asian/Pacific Islander | 8 | 1.8 | 2 | 2.3 | 2 | 1.7 | 2 | 1.7 | 2 | 1.7 |
| Hispanic/Latino | 12 | 2.7 | 3 | 3.4 | 2 | 1.7 | 2 | 1.7 | 5 | 4.3 |
| Other | 11 | 2.5 | 2 | 2.3 | 4 | 3.4 | 0 | 0.0 | 5 | 4.3 |
| Education | ||||||||||
| Some high school or high school graduate | 18 | 4.1 | 5 | 5.7 | 3 | 2.5 | 6 | 5.1 | 4 | 3.4 |
| Some college | 134 | 30.5 | 23 | 26.5 | 39 | 33.1 | 41 | 35.1 | 31 | 26.5 |
| College graduate and above | 287 | 65.4 | 59 | 67.8 | 76 | 64.4 | 70 | 59.8 | 82 | 70.1 |
| Family history of breast cancer | ||||||||||
| None | 286 | 62.1 | 54 | 67.8 | 80 | 65.0 | 76 | 65.0 | 76 | 65.0 |
| First degree | 81 | 16.1 | 14 | 18.6 | 22 | 22.2 | 26 | 22.2 | 19 | 16.2 |
| Second degree | 72 | 21.8 | 19 | 13.6 | 16 | 12.8 | 15 | 12.8 | 22 | 18.8 |
| Parity† | ||||||||||
| Nulliparous | 118 | 26.9 | 22 | 25.3 | 32 | 27.4 | 29 | 24.8 | 35 | 29.9 |
| 1 | 72 | 16.4 | 15 | 17.2 | 23 | 19.7 | 16 | 13.7 | 18 | 15.4 |
| 2 | 145 | 33.1 | 27 | 31.0 | 32 | 27.4 | 44 | 37.6 | 42 | 35.9 |
| ≥3 | 103 | 23.5 | 23 | 26.4 | 30 | 25.6 | 28 | 23.9 | 22 | 18.8 |
| History of breastfeeding, months‡ | ||||||||||
| 0 | 174 | 40.8 | 33 | 39.8 | 44 | 37.9 | 47 | 41.2 | 50 | 43.9 |
| 1-6 | 54 | 12.7 | 11 | 13.3 | 19 | 16.4 | 11 | 9.7 | 13 | 11.4 |
| ≥ 6 | 199 | 46.6 | 39 | 47.0 | 53 | 45.7 | 56 | 49.1 | 51 | 44.7 |
| History of breast biopsy | ||||||||||
| Yes | 58 | 13.2 | 14 | 16.1 | 17 | 14.4 | 10 | 8.6 | 17 | 14.5 |
| No | 381 | 86.8 | 73 | 83.9 | 101 | 85.6 | 107 | 91.5 | 100 | 85.5 |
| Age at randomization, years | ||||||||||
| < 60 | 304 | 69.3 | 62 | 74.7 | 83 | 70.3 | 80 | 68.4 | 79 | 67.5 |
| ≥ 60 | 135 | 30.8 | 25 | 28.7 | 35 | 29.7 | 37 | 31.6 | 38 | 32.5 |
| Age at menarche, years§ | ||||||||||
| < 13 | 209 | 48.0 | 44 | 50.6 | 54 | 46.2 | 55 | 47.0 | 56 | 48.7 |
| ≥ 13 | 227 | 52.0 | 43 | 49.4 | 63 | 53.9 | 62 | 53.0 | 59 | 51.3 |
| Age at menopause, years‖ | ||||||||||
| < 50 | 178 | 42.4 | 28 | 33.3 | 52 | 46.0 | 42 | 38.2 | 56 | 49.6 |
| ≥ 50 | 242 | 57.6 | 56 | 66.7 | 61 | 54.0 | 68 | 61.8 | 57 | 50.4 |
| Ever used hormone therapy | ||||||||||
| No | 178 | 40.5 | 37 | 42.5 | 53 | 44.9 | 49 | 41.9 | 39 | 33.3 |
| Yes | 261 | 59.5 | 50 | 57.5 | 65 | 55.1 | 68 | 58.1 | 78 | 66.7 |
| History of hysterectomy | ||||||||||
| No | 345 | 78.6 | 67 | 77.0 | 93 | 78.8 | 92 | 78.6 | 93 | 79.5 |
| Yes | 94 | 21.4 | 20 | 23.0 | 25 | 21.2 | 25 | 21.4 | 24 | 20.5 |
| History of bilateral oophorectomy | ||||||||||
| No | 416 | 94.8 | 83 | 95.4 | 112 | 94.9 | 109 | 93.2 | 112 | 95.7 |
| Yes | 23 | 5.2 | 4 | 4.6 | 6 | 5.1 | 8 | 6.8 | 5 | 4.3 |
| Sex hormones¶ | ||||||||||
| Estrone, pg/mL | ||||||||||
| Mean | 37.2 | 35.8 | 38.1 | 37.4 | 36.9 | |||||
| SD | 15.5 | 17.1 | 15.5 | 14.8 | 15.3 | |||||
| Estradiol, pg/mL | ||||||||||
| Mean | 12.7 | 12.4 | 12.7 | 12.6 | 12.8 | |||||
| SD | 5.8 | 6.1 | 5.4 | 5.4 | 6.3 | |||||
| Testosterone, ng/dL | ||||||||||
| Mean | 26.5 | 26.3 | 26.6 | 26.8 | 26.2 | |||||
| SD | 12.9 | 15.2 | 13.5 | 11.3 | 12.1 | |||||
| Androstenedione, ng/dL | ||||||||||
| Mean | 55.5 | 53.9 | 56.4 | 54.6 | 56.4 | |||||
| SD | 24.9 | 23.9 | 28.9 | 24.6 | 21.4 | |||||
| SHBG, nmol/L | ||||||||||
| Mean | 39.3 | 38.1 | 39.3 | 43.4 | 36.2 | |||||
| SD | 17.6 | 16.5 | 16.9 | 22.2 | 12.8 | |||||
| Free estradiol,# pg/mL | ||||||||||
| Mean | 0.35 | 0.34 | 0.35 | 0.34 | 0.36 | |||||
| SD | 0.17 | 0.16 | 0.16 | 0.16 | 0.18 | |||||
| Free testosterone, pg/mL | ||||||||||
| Mean | 5.7 | 5.6 | 5.8 | 5.5 | 5.8 | |||||
| SD | 2.8 | 2.9 | 2.9 | 2.5 | 2.7 | |||||
NOTE. SI conversion factors: To convert estrone to pmol/L, multiply by 3.699; estradiol to pmol/L, multiply by 3.67; testosterone to nmol/L, multiply by 0.0347; androstenedione to nmol/L, multiply by 0.0349.
Abbreviations: BMI, body mass index; SD, standard deviation; SHBG, sex hormone–binding globulin.
N = 427 for total; n = 85 for control; n = 114 for diet, exercise, and diet + exercise groups.
N = 438 for total; n = 87 for control; n = 117 for diet, exercise, and diet + exercise groups.
N = 427 for total; n = 83 for control; n = 116 for diet; n = 114 for exercise and diet + exercise groups.
N = 436 for total; n = 87 for control; n = 117 for diet and exercise groups; n = 115 for diet + exercise.
N = 420 for total; n = 84 for control; n = 113 for diet; n = 110 for exercise; n = 113 for diet + exercise.
N = 421 for total; n = 80 for control; n = 115 for diet; n = 110 for exercise; n = 116 for diet + exercise groups.
N = 420 for total; n = 79 for control; n = 115 for diet; n = 110 for exercise; n = 116 for diet + exercise group.