Table 4.

Associations of fish oil supplement use with subsets of breast cancer defined by histology and stage, among female VITAL participants (n = 35,016)

Fish oil*
NonuserCurrent user
Cases/noncasesHR (95% CI)Cases/noncasesHR (95% CI)
Histology
    Ductal carcinoma (n = 632)579/30,3311.00 (reference)29/2,6680.56 (0.38-0.83)
    Lobular carcinoma (n = 172)153/30,3311.00 (reference)13/2,6681.08 (0.59-1.96)
    P difference<0.05
SEER summary stage
    Local (n = 626)578/30,3311.00 (reference)29/2,6680.57 (0.38-0.84)
    Regional/distant (n = 251)221/30,3311.00 (reference)18/2,6680.97 (0.59-1.61)
    P difference0.06
Hormone receptor status
    ER+ (n = 737)669/30,3311.00 (reference)29/2,6680.64 (0.46-0.91)
    ER (n = 125)118/30,3311.00 (reference)1/2,6680.61 (0.27-1.40)
    P difference0.49
    PR+ (n = 640)584/30,3311.00 (reference)22/2,6680.63 (0.43-0.92)
    PR (n = 221)202/30,3311.00 (reference)8/2,6680.67 (0.36-1.23)
    P difference0.96
  • *Former users dropped from analysis.

  • Adjusted for age, race, education, BMI, height, fruit consumption, vegetable consumption, alcohol consumption, physical activity, age at menarche, age at menopause, age at first birth, history of hysterectomy, years of combined hormone therapy, family history of breast cancer, history of benign breast biopsy, mammography, low-dose aspirin use, regular aspirin use, ibuprofen use, naproxen use, use of multivitamins, memory loss, and CAD.