Table 3.

Adjusteda ORs and 95% CIs for associations of regular aspirin use with prostate cancer in the NCI Maryland prostate cancer case-control study

TotalAAEA
ControlCasebOR (95% CI)ControlCaseOR (95% CI)ControlCaseOR (95% CI)
Did you take aspirin regularly 1 year prior to interview?
No441 (46)410 (54)Ref.233 (52)238 (61)Ref.208 (40)172 (46)Ref.
Yes529 (54)351 (46)0.81 (0.66–1.00)220 (48)150 (39)0.71 (0.52–0.97)309 (60)201 (54)0.88 (0.66–1.17)
In the past 5 years, did you take at least 1 tablet daily?
No467 (46)427 (53)Ref.242 (50)248 (60)Ref.225 (42)179 (45)Ref.
Yes556 (54)384 (47)0.86 (0.71–1.06)239 (50)167 (40)0.70 (0.52–0.95)317 (58)217 (55)0.99 (0.74–1.31)
In the past 5 years, how long did you regularly take aspirin?
Did not use441 (43)410 (51)Ref.233 (49)238 (58)Ref.208 (39)172 (44)Ref.
≤3 years174 (17)146 (18)0.94 (0.72–1.23)89 (19)71 (17)0.79 (0.53–1.17)85 (16)75 (19)1.12 (0.76–1.64)
>3 years401 (39)250 (31)0.79 (0.63–0.99)157 (33)103 (25)0.68 (0.48–0.96)244 (45)147 (37)0.84 (0.62–1.15)
Ptrend = 0.04Ptrend = 0.03Ptrend = 0.28
Among users who took at least 1 tablet daily, how long did they regularly take aspirin?
Did not use467 (46)427 (53)Ref.242 (51)248 (59)Ref.225 (42)179 (45)Ref.
≤3 years158 (16)138 (17)1.00 (0.76–1.32)82 (17)65 (16)0.78 (0.52–1.17)76 (14)73 (19)1.28 (0.87–1.90)
>3 years390 (38)240 (30)0.79 (0.63–0.99)154 (32)99 (25)0.65 (0.46–0.92)236 (44)141 (36)0.87 (0.64–1.18)
Ptrend = 0.04Ptrend = 0.01Ptrend = 0.39
• NOTE: Column total sums that differ are due to missing data, N (%). Bolded data indicate significant associations in the logistic regression analysis.

• aUnconditional logistic regression adjusted for age at study entry, BMI (kg/m2), diabetes (yes/no), education (high school or less, some college, college, professional school), family history of prostate cancer (first-degree relatives, yes/no), race (not included in stratified analysis), smoking history (never, former, current), Tylenol (yes/no), and pain relievers not containing Tylenol or aspirin-containing compounds (yes/no).

• bCases recruited within 1 year after disease diagnosis with an average interval between diagnosis and enrollment of 4.8 months.