Table 2.
Factors associated with percent mammographic density, relative telomere length and urinary MDA (multiple regression; n = 305).
| Characteristic | Percent Mammographic Density (square root)a | Relative telomere lengtha,b | Urinary MDA (log)a | ||||||
|---|---|---|---|---|---|---|---|---|---|
| Beta | SE | p value | Beta | SE | p value | Beta | SE | p value | |
| Age (years) | −0.003 | 0.02 | 0.90 | −0.005 | 0.002 | 0.02 | −0.008 | 0.006 | 0.16 |
| Waist Circumferencec (cm) | −679.6 | 45.0 | <0.0001 | −6.88 | 4.62 | 0.14 | 16.82 | 11.5 | 0.15 |
| Height (cm) | −0.003 | 0.02 | 0.85 | 0.002 | 0.002 | 0.30 | 0.01 | 0.004 | 0.004 |
| Age at Menarche (years) | 0.04 | 0.07 | 0.52 | −0.009 | 0.007 | 0.21 | −0.02 | 0.02 | 0.26 |
| Parity (Yes vs no) | −0.20 | 0.23 | 0.23 | −0.005 | 0.02 | 0.83 | −0.02 | 0.06 | 0.78 |
| Age at First Child (years) | 0.06 | 0.02 | 0.01 | 0.002 | 0.002 | 0.47 | 0.007 | 0.006 | 0.22 |
| Menopausal Status Post vs Premenopausal | −0.05 | 0.34 | 0.88 | −0.08 | 0.05 | 0.02 | 0.32 | 0.09 | 0.0003 |
| Family History of Breast Cancer Yes vs No | 0.10 | 0.24 | 0.70 | −0.02 | 0.03 | 0.43 | 0.02 | 0.06 | 0.77 |
| Current Smoking Smoker vs non smoker | −0.42 | 0.32 | 0.19 | −0.07 | 0.03 | 0.03 | 0.15 | 0.08 | 0.07 |
| Urinary MDA (log) | 0.37 | 0.23 | 0.10 | 0.05 | 0.02 | 0.02 | n/a | n/a | n/a |
| R square for model | 49% | 23% | 11% | ||||||
MDA = malondialdehyde; RTL = relative telomere length; SE = standard error; n/a = not applicable.
aOutcome measure for regression analysis.
bAdjusted for batch of PCR analysis; cNegative inverse transformed.