Table 4.
Association between SULT1A1 genotypes and mammographic breast density† of study population by number of pregnancies: Group Health, Seattle, WA 2004 – 2005
| Number of live births | SULT1A1 genotype | n* (%) | Mean§ (95%CI) | Absolute % diff | p-value | p trend |
|---|---|---|---|---|---|---|
| 0 | R213/R213 | 26 (16.7) | 49.3 (40.3, 58.4) | Reference | -- | 0.05 |
| R213/H213 | 16 (10.2) | 41.3 (32.8, 49.9) | −8.0 | 0.21 | ||
| H213/H213 | 8 (5.1) | 30.4 (12.5, 48.3) | −18.9 | 0.07 | ||
| 1–2 | R213/R213 | 38 (24.4) | 38.6 (31.1, 46.1) | Reference | -- | 0.05 |
| R213/H213 | 33 (21.2) | 33.6 (25.7, 41.4) | −5.0 | 0.38 | ||
| H213/H213 | 13 (8.3) | 25.1 (15.4, 34.8) | −13.4 | 0.04 | ||
| 3+ | R213/R213 | 9 (5.8) | 31.3 (13.0, 49.6) | Reference | -- | 0.30 |
| R213/H213 | 7 (4.5) | 23.4 (6.7, 40.1) | −7.9 | 0.52 | ||
| H213/H213 | 6 (3.8) | 19.1 (3.6, 34.7) | −12.2 | 0.31 | ||
*
number does not add up to 175 because 19 participants were missing data on number of live births;
§
adjusted for ethnicity using least squares regression;
†
p-value (interaction) = 0.83