Table 2.
Hazard ratios (HRs) and 95% confidence intervals (CIs) for the associations between pubertal timing and tempo and incident breast cancer in the Sister Study cohort
| Person-years | N cases | Minimally adjusteda | Fully adjustedb | Mutually adjustedc | ||||
|---|---|---|---|---|---|---|---|---|
| HR | 95% CI | HR | 95% CI | HR | 95% CI | |||
| Age at pubertal milestone | ||||||||
| Age at thelarche | ||||||||
| < 10 years | 15,806 | 135 | 1.22 | 1.03, 1.46 | 1.23 | 1.03, 1.46 | 1.15 | 0.95, 1.39 |
| 10–11 years | 125,803 | 921 | 1.02 | 0.95, 1.11 | 1.03 | 0.95, 1.11 | 0.98 | 0.90, 1.08 |
| 12–13 years | 238,712 | 1725 | 1.00 | Referent | 1.00 | Referent | 1.00 | Referent |
| > 13 years | 79,405 | 514 | 0.91 | 0.82, 1.00 | 0.91 | 0.82, 1.00 | 0.93 | 0.84, 1.04 |
| Continuous (per 1-year later) | 459,726 | 3295 | 0.97 | 0.95, 0.99 | 0.97 | 0.95, 0.99 | 0.99 | 0.96, 1.02 |
| Age at menarche | ||||||||
| < 12 years | 93,485 | 742 | 1.10 | 1.01, 1.20 | 1.10 | 1.01, 1.20 | 1.09 | 0.99, 1.20 |
| 12–13 years | 258,756 | 1849 | 1.00 | Referent | 1.00 | Referent | 1.00 | Referent |
| > 13 years | 107,484 | 704 | 0.92 | 0.84, 1.00 | 0.92 | 0.85, 1.01 | 0.95 | 0.86, 1.04 |
| Continuous (per 1-year later) | 459,726 | 3295 | 0.96 | 0.94, 0.98 | 0.96 | 0.94, 0.98 | 0.97 | 0.94, 1.00 |
| Age reached adult height | ||||||||
| < 15 years | 116,762 | 878 | 0.97 | 0.89, 1.06 | 0.97 | 0.89, 1.06 | 0.94 | 0.86, 1.03 |
| 15–17 years | 188,674 | 1412 | 1.00 | Referent | 1.00 | Referent | 1.00 | Referent |
| > 17 years | 154,289 | 1005 | 0.87 | 0.80, 0.94 | 0.87 | 0.80, 0.95 | 0.88 | 0.81, 0.95 |
| Continuous (per 1-year later) | 459,726 | 3295 | 0.99 | 0.97, 1.00 | 0.99 | 0.97, 1.00 | 0.99 | 0.98, 1.01 |
| Pubertal tempo | ||||||||
| Time from thelarche to menarche | ||||||||
| < 0 years | 81,423 | 592 | 1.01 | 0.92, 1.11 | 1.01 | 0.92, 1.11 | 1.06 | 0.95, 1.17 |
| 0 years | 169,355 | 1239 | 1.00 | Referent | 1.00 | Referent | 1.00 | Referent |
| 1 year | 130,298 | 913 | 0.97 | 0.89, 1.05 | 0.96 | 0.89, 1.05 | 0.95 | 0.87, 1.03 |
| > 1 year | 78,650 | 551 | 0.99 | 0.90, 1.10 | 1.00 | 0.90, 1.10 | 0.96 | 0.86, 1.06 |
| Continuous (per 1-year longer) | 459,726 | 3295 | 0.99 | 0.97, 1.02 | 0.99 | 0.97, 1.02 | 0.97 | 0.94, 1.00 |
| Time from menarche to adult height | ||||||||
| < 2 years | 95,450 | 702 | 0.98 | 0.89, 1.08 | 0.98 | 0.89, 1.08 | 0.99 | 0.90, 1.09 |
| 2–3 years | 137,145 | 973 | 0.97 | 0.89, 1.06 | 0.97 | 0.89, 1.06 | 0.98 | 0.89, 1.07 |
| 4–5 years | 134,086 | 971 | 1.00 | Referent | 1.00 | Referent | 1.00 | Referent |
| > 5 years | 93,045 | 649 | 0.96 | 0.87, 1.06 | 0.96 | 0.87, 1.06 | 0.93 | 0.84, 1.03 |
| Continuous (per 1-year longer) | 459,726 | 3295 | 1.00 | 0.99, 1.02 | 1.00 | 0.99, 1.02 | 0.99 | 0.98, 1.01 |
N = 49,686 women included in each model. No violations of proportional hazards assumption for any of the exposures of interest
aAdjusted for attained age as the underlying time scale and stratified by birth cohort
bAdditionally adjusted for race/ethnicity and family income level growing up
cFully adjusted model with mutual adjustment for ages at thelarche and menarche. Age reached adult height is adjusted for age at menarche. Pubertal tempo models are adjusted for age at thelarche (for the thelarche-menarche model) and age at menarche (for the menarche-height model)