Table 2.

Associations between specialty supplement use and breast cancer risk among female VITAL participants (n = 35,016)

SupplementCases (n = 880), n (%)Noncases (n = 34,136), n (%)Age-adjusted HR (95% CI)Multivariable-adjusted HR (95% CI)*
Anti-inflammatory supplements
    Glucosamine
        Nonuser649 (74.1)25,766 (75.9)1.00 (reference)1.00 (reference)
        Former46 (5.3)1,510 (4.5)1.21 (0.89-1.63)1.27 (0.93-1.74)
        Current181 (20.7)6,694 (19.7)1.02 (0.86-1.20)1.07 (0.90-1.29)
        P trend0.680.36
    10-y average use
        Nonuser649 (74.1)25,766 (75.9)1.00 (reference)1.00 (reference)
        Low155 (17.7)5,369 (15.8)1.11 (0.93-1.32)1.18 (0.98-1.42)
        High72 (8.2)2,835 (8.4)0.95 (0.75-1.22)0.98 (0.75-1.27)
        P trend0.840.56
    Chondroitin
        Nonuser724 (82.7)28,409 (83.5)1.00 (reference)1.00 (reference)
        Former31 (3.5)1,094 (3.2)1.10 (0.77-1.58)1.12 (0.77-1.64)
        Current121 (13.8)4,513 (13.3)1.00 (0.82-1.21)1.07 (0.87-1.31)
        P trend0.960.51
    10-y average use
        Nonuser724 (82.7)28,409 (83.5)1.00 (reference)1.00 (reference)
        Low101 (11.5)3,721 (10.9)1.02 (0.83-1.26)1.09 (0.87-1.36)
        High51 (5.8)1,886 (5.5)1.00 (0.75-1.33)1.05 (0.78-1.42)
        P trend0.910.54
    Methylsulfonylmethane
        Nonuser826 (94.1)32,056 (94.1)1.00 (reference)1.00 (reference)
        Former10 (1.1)397 (1.2)0.99 (0.53-1.85)1.01 (0.52-1.96)
        Current42 (4.8)1,612 (4.7)0.99 (0.73-1.35)1.02 (0.74-1.42)
        P trend0.950.89
    10-y average use
        Nonuser826 (94.1)32,056 (94.1)1.00 (reference)1.00 (reference)
        Low45 (5.3)1,612 (4.7)1.07 (0.79-1.44)1.10 (0.80-1.51)
        High7 (0.8)397 (1.2)0.68 (0.32-1.44)0.69 (0.31-1.54)
        P trend0.670.82
    Fish oil
        Nonuser802 (91.2)30,331 (89.2)1.00 (reference)1.00 (reference)
        Former30 (3.4)998 (2.9)1.16 (0.81-1.67)1.07 (0.71-1.60)
        Current47 (5.4)2,668 (7.9)0.67 (0.50-0.90)0.68 (0.50-0.92)
        P trend0.020.02
    10-y average use
        Nonuser802 (91.2)30,331 (89.2)1.00 (reference)1.00 (reference)
        Low41 (4.7)2,160 (6.4)0.74 (0.54-1.01)0.75 (0.54-1.04)
        High36 (4.1)1,506 (4.4)0.89 (0.64-1.24)0.82 (0.57-1.18)
        P trend0.140.09
    Grapeseed
        Nonuser848 (96.8)32,672 (95.9)1.00 (reference)1.00 (reference)
        User28 (3.2)1,381 (4.1)0.80 (0.55-1.16)0.78 (0.52-1.17)
Taken for climacteric symptoms
    Black cohosh
        Nonuser858 (97.6)33,087 (97.2)1.00 (reference)1.00 (reference)
        Users21 (2.4)964 (2.8)1.04 (0.67-1.60)1.17 (0.75-1.82)
    Dong quai
        Nonuser864 (98.2)33,459 (98.7)1.00 (reference)1.00 (reference)
        Users16 (1.8)426 (1.3)1.18 (0.72-1.93)1.27 (0.76-2.13)
    Soy supplement
        Nonuser843 (95.9)32,510 (95.4)1.00 (reference)1.00 (reference)
        User36 (4.1)1,553 (4.6)0.98 (0.70-1.37)1.04 (0.74-1.48)
    St. John's wort
        Nonuser827 (94.5)31,909 (93.8)1.00 (reference)1.00 (reference)
        Former28 (3.2)1,396 (4.1)0.87 (0.59-1.26)0.83 (0.55-1.24)
        Current20 (2.3)713 (2.1)1.16 (0.75-1.81)1.18 (0.74-1.89)
        P trend0.890.95
    10-y average use
        Nonuser827 (94.5)31,909 (93.8)1.00 (reference)1.00 (reference)
        Low40 (4.6)1,595 (4.7)1.07 (0.78-1.47)1.05 (0.75-1.47)
        High8 (0.9)514 (1.5)0.66 (0.33-1.33)0.63 (0.30-1.33)
        P trend0.540.46
    Combined climacteric supplements
        Nonuser782 (89.27)29,983 (88.25)1.00 (reference)1.00 (reference)
        User94 (10.73)3,991 (11.75)1.01 (0.81-1.26)1.01 (0.80-1.27)
Other specialty supplements
    Acidophilus
        Nonuser842 (95.7)32,040 (94.4)1.00 (reference)1.00 (reference)
        Former17 (1.9)881 (2.6)0.78 (0.48-1.26)0.73 (0.55-1.23)
        Current21 (2.4)1,034 (3.1)0.79 (0.52-1.23)0.83 (0.52-1.31)
        P trend0.180.23
    10-y average use
        Nonuser842 (95.7)32,040 (94.4)1.00 (reference)1.00 (reference)
        Low28 (3.2)1,320 (3.9)0.84 (0.58-1.23)0.82 (0.55-1.23)
        High10 (1.1)595 (1.8)0.67 (0.36-1.25)0.69 (0.36-1.33)
        P trend0.120.15
    Coenzyme Q10
        Nonuser815 (92.8)31,503 (92.6)1.00 (reference)1.00 (reference)
        Former16 (1.8)792 (2.3)0.81 (0.50-1.33)0.76 (0.45-1.30)
        Current47 (5.4)1,744 (5.1)1.04 (0.77-1.39)1.05 (0.77-1.43)
        P trend0.990.99
    10-y average use
        Nonuser815 (92.8)31,503 (92.6)1.00 (reference)1.00 (reference)
        Low37 (4.2)1,603 (4.7)0.92 (0.66-1.27)0.92 (0.65-1.29)
        High26 (3.0)933 (2.7)1.06 (0.71-1.56)1.04 (0.69-1.58)
        P trend0.960.92
    Garlic pills
        Nonuser789 (90.2)30,101 (88.6)1.00 (reference)1.00 (reference)
        Former34 (3.9)1,612 (4.8)0.81 (0.57-1.14)0.86 (0.60-1.22)
        Current52 (5.9)2,252 (6.6)0.83 (0.63-1.10)0.84 (0.62-1.13)
        P trend0.110.18
    10-y average use§
        Nonuser779 (89.0)29,871 (88.0)1.00 (reference)1.00 (reference)
        Low56 (6.4)2,346 (6.9)0.92 (0.70-1.20)0.99 (0.74-1.31)
        High40 (4.6)1,748 (5.2)0.82 (0.60-1.13)0.83 (0.59-1.16)
        P trend0.190.31
    Ginkgo biloba
        Nonuser774 (88.3)29,592 (87.1)1.00 (reference)1.00 (reference)
        Former47 (5.4)1,707 (5.0)1.09 (0.81-1.47)1.06 (0.77-1.45)
        Current56 (6.4)2,664 (7.8)0.81 (0.62-1.06)0.85 (0.64-1.13)
        P trend0.210.36
    10-y average use§
        Nonuser755 (86.1)28,794 (84.8)1.00 (reference)1.00 (reference)
        Low82 (9.4)3,441 (10.1)0.94 (0.75-1.18)0.98 (0.77-1.25)
        High40 (4.6)1,728 (5.1)0.88 (0.64-1.21)0.88 (0.63-1.24)
        P trend0.360.51
    Ginseng
        Nonuser835 (95.0)31,986 (94.1)1.00 (reference)1.00 (reference)
        Former22 (2.5)963 (2.8)0.94 (0.62-1.44)0.91 (0.58-1.44)
        Current22 (2.5)1,045 (3.1)0.87 (0.57-1.32)0.94 (0.61-1.46)
        P trend0.480.69
    10-y average use§
        Nonuser811 (92.3)31,167 (91.7)1.00 (reference)1.00 (reference)
        Low53 (6.0)2,160 (6.4)1.02 (0.77-1.35)1.08 (0.80-1.44)
        High15 (1.7)667 (2.0)0.91 (0.55-1.52)0.85 (0.48-1.50)
        P trend0.870.92
    Melatonin
        Nonuser831 (94.8)32,007 (94.1)1.00 (reference)1.00 (reference)
        Former26 (3.0)920 (2.7)1.01 (0.68-1.49)0.93 (0.61-1.42)
        Current20 (2.3)1,090 (3.2)0.86 (0.55-1.34)0.87 (0.54-1.39)
        P trend0.560.51
    10-y average use
        Nonuser831 (94.8)32,007 (94.1)1.00 (reference)1.00 (reference)
        Low33 (3.8)1,583 (4.7)0.85 (0.60-1.21)0.86 (0.60-1.23)
        High13 (1.5)427 (1.3)1.25 (0.72-2.16)1.09 (0.58-2.04)
        P trend0.970.70
  • *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, and use of multivitamins.

  • Additionally adjusted for history of osteoarthritis (glucosamine, chondroitin, methylsulfonylmethane), chronic joint pain (glucosamine, chondroitin, methylsulfonylmethane), memory loss (fish oil, coenzyme q10, ginkgo biloba), CAD (fish oil, grapeseed), lactose intolerance (acidophilus), diabetes (dong quai), insomnia (melatonin), and depression (St. John's wort).

  • Ten-year average use: nonuser; low use, <4 d/week or <3 y; and high use, ≥4 d/week and ≥3 y.

  • §Including multivitamin sources; those with only multivitamin source coded as “low” 10-y average use.