Table 2.

Association between regular aspirin and acetaminophen use and endometrial cancer—Roswell Park Cancer Institute (1982-1998)

Cases, n (%)Controls, n (%)OR (95% CI)Adjusted OR (95% CI)*
Regular aspirin user
    No249 (58.3)252 (59.0)Ref.Ref.
    Yes178 (41.7)175 (41.0)1.03 (0.78-1.35)0.91 (0.66-1.26)
Frequency of aspirin use
    Used one to six times per week118 (27.6)111 (26.0)1.08 (0.79-1.47)1.00 (0.69-1.46)
    Used more than seven times per week60 (14.1)64 (15.0)0.95 (0.64-1.41)0.77 (0.49-1.22)
Duration of aspirin use
    Used for 1 to 10 years82 (19.2)83 (19.4)1.00 (0.70-1.42)0.77 (0.51-1.17)
    Used for >10 years96 (22.5)92 (21.5)1.06 (0.76-1.48)1.05 (0.71-1.56)
Cumulative aspirin use
    Moderate use (≤10 tablet-yrs)116 (27.2)122 (28.6)0.96 (0.71-1.31)0.79 (0.55-1.14)
    High use (>10 tablet-yrs)62 (14.5)53 (12.4)1.18 (0.79-1.78)1.20 (0.75-1.92)
Regular acetaminophen user
    No361 (84.5)378 (88.5)Ref.Ref.
    Yes66 (15.5)49 (11.5)1.41 (0.95-2.10)0.96 (0.60-1.54)
Frequency of acetaminophen use
    Used one to six times per week53 (12.4)39 (9.1)1.42 (0.92-2.21)0.92 (00.55-1.56)
    Used more than seven times per week13 (3.0)10 (2.3)1.36 (0.59-3.14)1.12 (0.42-2.98)
Duration of acetaminophen use
    Used for 1 to 10 years45 (10.5)29 (6.8)1.63 (0.997-2.65)1.55 (0.65-2.05)
    Used for >10 years21 (4.9)20 (4.7)1.10 (0.59-2.06)0.69 (0.33-1.46)
Cumulative acetaminophen use
    Moderate use (≤ 10 tablet-yrs)59 (13.8)38 (8.9)1.63 (1.06-2.51)1.08 (0.65-1.77)
    High use (>10 tablet-yrs)7 (1.6)11 (2.6)0.67 (0.26-1.74)0.49 (0.15-1.60)
  • * Adjusted for age, education, BMI, parity, age at menarche, age at menopause and parity.

  • Nonuser group served as reference group for all regression analyses. User defined as use of at least one tablet a week for at least 6 months.

  • Tablet-years defined as average number of tablets per day × years of use.