Table 3.

Breast cancer incidence by duration of regular NSAID use, CPS-II Nutrition Cohort, 1992-2001

Cases/person-yearsMultivariate-adjusted rate ratios (95% CI)*
Total NSAIDs
    No reported use393/84,8141.00 (reference)
    Past or less than regular use only1,781/316,1011.15 (1.03-1.29)
    Current regular use, <5-y duration656/118,1571.16 (1.02-1.31)
    Current regular use, ≥5-y duration178/29,9721.05 (0.88-1.26)
Aspirin
    No reported use565/114,5861.00 (reference)
    Past or less than regular use only1,999/350,3561.11 (1.01-1.22)
    Current regular use, <5-y duration370/68,9401.08 (0.94-1.23)
    Current regular use, ≥5-y duration74/15,1620.88 (0.69-1.12)
Ibuprofen
    No reported use681/113,4721.00 (reference)
    Past or less than regular use only365/58,9490.99 (0.87-1.13)
    Current regular use, <5-y duration61/9,4861.02 (0.79-1.33)
    Current regular use, ≥5-y duration35/4,2601.29 (0.92-1.82)
Other NSAIDs
    No reported use931/153,8821.00 (reference)
    Past or less than regular use only135/21,5030.97 (0.81-1.17)
    Current regular use, <5-y duration55/7,2901.17 (0.89-1.53)
    Current regular use, ≥5-y duration21/3,4920.90 (0.58-1.40)
  • NOTE: Regular use is defined as ≥30 pills per month.

  • * Rate ratios adjusted for age, race, education, family history of breast cancer, personal history of breast cysts, history of mammography, age at menarche, duration of oral contraceptive use, parity, age at menopause, use of hormone replacement therapy, weight change, body mass index, and alcohol consumption. Rate ratios for duration of each type of NSAID are also adjusted for duration of use of other NSAID types.

  • Includes only follow-up from 1997-2001 because duration of use of this NSAID could not be estimated until 1997.