Table 4.
Correlation between mitotic index, host factors and reproductive factors in healthy controls (N = 360).
| Host factors | N (%) | Mean (SD) | N (%) | Mean (SD) | N (%) | Mean (SD) |
|---|---|---|---|---|---|---|
| All (N = 360) | White (N = 224) | African American (N = 126) | ||||
| Race | 360 | 3.25 (1.0) | 224 | 3.35 (1.0) | 126 | 3.06 (0.9) |
| Age categories (y) | ||||||
| ≤45 | 78 (22) | 3.39 (1.0) | 45 | 3.40 (0.9) | 31 (25) | 3.22 (0.9) |
| 46–55 | 118 (33) | 3.26 (0.9) | 71 | 3.39 (1.0) | 42 (33) | 3.00 (0.8) |
| 56–65 | 102 (28) | 3.30 (1.0) | 63 | 3.46 (1.0) | 36 (28) | 3.08 (0.9) |
| ≥66 | 62 (17) | 3.01 (1.0) | 45 | 3.07 (0.9) | 17 (14) | 2.84 (1.1) |
| P trend | 0.06 | 0.19 | 0.28 | |||
| BMI | ||||||
| <20 | 19 (5) | 3.63 (0.9) | 16 (7) | 3.78 (1.0) | 2 (2) | 2.34 (0.1) |
| 20–25 | 135 (38) | 3.49 (1.0) | 107 (48) | 3.53 (0.9) | 23 (18) | 3.27 (1.0) |
| 26–30 | 88 (24) | 3.10 (0.9) | 48 (21) | 3.11 (1.0) | 36 (29) | 3.09 (1.0) |
| >30 | 105 (29) | 3.00 (0.9) | 46 (21) | 3.08 (1.0) | 59 (47) | 2.92 (0.8) |
| P trend | <0.01 | <0.01 | 0.32 | |||
| Reproductive factors | ||||||
| Age at menarche (y) | ||||||
| 9–11 | 86 (24) | 3.12 (1.0) | 45 (20) | 3.23 (1.0) | 39 (31) | 3.02 (1.0) |
| 12 | 110 (30) | 3.35 (0.9) | 70 (31) | 3.35 (1.0) | 35 (28) | 3.19 (1.0) |
| 13 | 85 (24) | 3.22 (1.0) | 54 (24) | 3.38 (0.9) | 28 (22) | 2.97 (1.0) |
| ≥14 | 76 (21) | 3.34 (0.9) | 53 (24) | 3.47 (1.0) | 23 (18) | 3.05 (0.9) |
| P trend | 0.04 | <0.01 | 0.65 | |||
| FTP | ||||||
| Never pregnant | 69 (19) | 3.29 (1.0) | 47 (21) | 3.30 (1.0) | 19 (15) | 3.23 (1.0) |
| No FTP | 34 (9) | 3.42 (0.9) | 17 (8) | 3.70 (0.9) | 17 (13) | 3.11 (0.8) |
| Yes FTP | 254 (71) | 3.23 (1.0) | 158 (70) | 3.34 (1.0) | 89 (71) | 3.01 (0.8) |
| P value | 0.06 | 0.34 | 0.48 | |||
| Number of FTP | ||||||
| 1 | 57 (22) | 3.01 (1.0) | 33 (21) | 3.11 (1.0) | 23 (26) | 2.93 (0.9) |
| 2 | 112 (44) | 3.31 (0.9) | 74 (47) | 3.35 (1.0) | 35 (39) | 3.16 (0.9) |
| ≥3 | 85 (34) | 3.26 (1.0) | 51 (32) | 3.45 (1.1) | 31 (35) | 2.89 (0.9) |
| P trend | 0.13 | <0.01 | 0.94 | |||
| Age of first FTP (y) | ||||||
| ≤20 | 30 (12) | 2.92 (1.1) | 3 (2) | 2.84 (0.9) | 25 (28) | 2.85 (0.9) |
| 21–24 | 59 (24) | 2.99 (1.0) | 31 (19) | 3.14 (1.1) | 27 (31) | 2.77 (0.9) |
| 25–29 | 64 (26) | 3.50 (1.0) | 44 (28) | 3.63 (1.0) | 17 (19) | 3.21 (1.0) |
| ≥30 | 94 (38) | 3.30 (1.0) | 74 (47) | 3.28 (1.0) | 19 (21) | 3.37 (1.0) |
| P trend | 0.04 | 0.6 | 0.08 | |||
| Age of last FTP | ||||||
| <30 | 78 (31) | 3.14 (1.1) | 33 (21) | 3.44 (1.1) | 41 (46) | 2.73 (0.9) |
| 30–35 | 83 (33) | 3.27 (1.0) | 56 (36) | 3.38 (1.0) | 25 (28) | 3.18 (0.8) |
| 36–40 | 67 (26) | 3.35 (1.1) | 48 (30) | 3.38 (0.9) | 18 (20) | 3.28 (0.9) |
| ≥40 | 23 (9) | 3.02 (1.0) | 18 (11) | 2.94 (1.3) | 5 (6) | 3.45 (1.3) |
| P trend | 0.23 | 0.27 | 0.03 | |||
| Years since last FTP | ||||||
| ≤10 | 51 (20) | 3.29 (1.5) | 36 (23) | 3.10 (1.0) | 14 (16) | 3.35 (0.7) |
| 11–20 | 56 (22) | 3.24 (1.1) | 36 (23) | 3.23 (1.3) | 18 (20) | 3.26 (0.9) |
| 21–30 | 68 (27) | 3.29 (1.0) | 36 (23) | 3.53 (0.9) | 32 (36) | 3.00 (1.0) |
| ≥30 | 76 (30) | 3.12 (1.6) | 47 (29) | 3.48 (1.0) | 25 (28) | 2.63 (0.9) |
| P trend | 0.23 | 0.37 | 0.3 | |||
| Ever breastfed | ||||||
| Yes | 178 (70) | 3.28 (1.0) | 130 (82) | 3.40 (1.0) | 44 (49) | 3.13 (0.9) |
| No | 76 (30) | 3.13 (1.0) | 28 (18) | 3.32 (1.0) | 45 (51) | 2.94 (0.9) |
| P value | 0.23 | 0.7 | 0.36 | |||
| Weeks breast feeding | ||||||
| ≤20 | 43 (24) | 3.07 (1.0) | 28 (22) | 3.20 (1.0) | 14 (32) | 2.93 (0.9) |
| 21–56 | 41 (23) | 3.24 (1.0) | 29 (22) | 3.09 (1.0) | 12 (27) | 3.64 (0.8) |
| 57–108 | 43 (24) | 3.48 (1.0) | 36 (28) | 3.49 (1.1) | 6 (14) | 2.89 (1.2) |
| ≥109 | 47 (27) | 3.39 (1.0) | 35 (27) | 3.48 (1.1) | 10 (23) | 2.92 (1.0) |
| P trend | 0.11 | 0.12 | 0.91 | |||
Notes: *P-trend and P-values were computed using general linear models adjusting for age and race apart from when age, race and menopausal status were examined. For analysis stratified by race, age adjusted values are presented.
Abbreviations: FTP, full term pregnancy, analyses among parous women only, weeks breast feeding analysis was performed among women who breast fed; BMI, body mass index.