Table 3.

HRs and 95% CIs for breast cancer associated with solvent job exposure by estrogen receptor status

ER+ tumorsER tumors
CasesaCasesa
N = 968AdjustedN = 197Adjusted
Person-yearsn (%)HRb (95% CI)Person-yearsn (%)HRb (95% CI)
Solvent job
 Ever30,373132 (14)1.15 (0.95–1.39)30,37327 (14)0.91 (0.58–1.43)
 Never194,930836 (86)Ref194,930170 (86)Ref
Total duration of solvent job(s) exposure, y
 10+12,58459 (6)1.20 (0.92–1.57)12,58414 (7)1.07 (0.58–1.97)
 5 to <107,36832 (3)1.20 (0.83–1.71)7,3684 (2)0.35 (0.09–1.40)
 1 to <510,42241 (4)1.06 (0.77–1.46)10,4229 (5)1.11 (0.57–2.19)
 Never194,930836 (86)Ref194,930170 (86)Ref
 TrendcP = 0.62P = 0.75
Frequency of solvent exposure
 1+/wk6,66131 (3)1.12 (0.77–1.63)6,6615 (3)0.55 (0.18–1.74)
 <1/wk23,02798 (10)1.16 (0.94–1.44)23,02722 (11)1.05 (0.65–1.70)
 Never194,930836 (87)Ref194,930170 (86)Ref
Time period of first solvent job
 Before 198014,89380 (8)1.28 (1.01–1.62)14,89316 (8)1.01 (0.57–1.79)
 1980 and after15,44052 (5)1.00 (0.75–1.34)15,44011 (6)0.80 (0.40–1.57)
 Never194,930836 (86)Ref194,930170 (86)Ref
Time since last solvent job at baseline interview
 5+ y20,16996 (10)1.22 (0.98–1.51)20,16916 (8)0.74 (0.41–1.34)
 Current to <5 y10,16436 (4)1.01 (0.72–1.42)10,16411 (6)1.27 (0.66–2.42)
 Never194,930836 (86)Ref194,930170 (86)Ref
Age at first solvent job at baseline interview
 35+ y7,32833 (3)1.14 (0.80–1.62)7,3287 (4)1.00 (0.44–2.27)
 25 to <35 y8,44532 (3)1.00 (0.70–1.45)8,4458 (4)1.02 (0.48–2.19)
 20 to <25 y7,90334 (4)1.14 (0.80–1.62)7,9034 (2)0.32 (0.08–1.30)
 <20 y6,65833 (3)1.38 (0.97–1.97)6,6588 (4)1.40 (0.65–2.99)
 Never194,930836 (86)Ref194,930170 (86)Ref
 TrendcP = 0.54P = 0.68
Timing of first solvent job
 Before first birth9,61248 (5)1.39 (1.03–1.86)9,6128 (4)1.00 (0.47–2.15)
 After first birth14,49757 (6)1.06 (0.79–1.41)14,49715 (8)0.90 (0.48–1.68)
 Nulliparous6,18927 (3)1.03 (0.69–1.54)6,1894 (2)0.82 (0.29–2.29)
 Never194,930836 (86)Ref194,930170 (86)Ref
Duration of solvent job(s) exposure relative to first birthd
 5+ y before first birth3,04518 (2)1.56 (0.97–2.50)3,0452 (1)0.91 (0.22–3.73)
 3 to <5 y before first birth2,76313 (2)1.28 (0.74–2.23)2,7635 (3)1.98 (0.73–5.37)
 <3 y before first birth3,80417 (2)1.14 (0.70–1.88)3,8041 (1)0.33 (0.05–2.38)
 After first birth14,49757 (7)1.05 (0.79–1.40)14,49715 (9)0.88 (0.47–1.65)
 Never159,475689 (87)Ref159,475141 (86)Ref
 TrendcP = 0.05P = 0.76

NOTE: Differences in the total numbers of cases are due to missing values. Significant values (<0.05) are in bold font.

  • aExcluding cases missing information on estrogen receptor status.

  • bHRs are adjusted for race/ethnicity, education, income, parity, and age at first birth.

  • cTest for trend among solvent-exposed only.

  • dAmong parous women only.