A large cohort study of aspirin and other nonsteroidal anti-inflammatory drugs and prostate cancer incidence.
BACKGROUND
Use of aspirin and other nonsteroidal anti-inflammatory drugs (NSAIDs) has consistently been associated with a reduced risk of colon cancer. Recent epidemiologic studies have suggested that the use of NSAIDs, particularly aspirin, may also be associated with a reduced risk of prostate cancer, but the evidence remains limited.


METHODS
We examined the association between NSAID use and prostate cancer incidence among 70 144 men in the American Cancer Society's Cancer Prevention Study II Nutrition Cohort. Information on NSAID use was obtained from a questionnaire completed at study enrollment in 1992-1993 and was updated using follow-up questionnaires in 1997 and 1999. We calculated rate ratios (RRs) and 95% confidence intervals (CIs) for prostate cancer incidence associated with NSAID use, adjusting for age and potential prostate cancer risk factors.


RESULTS
During follow-up from 1992-1993 through August 31, 2001, 4853 cases of incident prostate cancer were identified. Neither current aspirin use nor current use of NSAIDs (aspirin and other NSAIDs combined) was associated with prostate cancer risk, even at the highest usage level (60 or more pills per month). However, long-duration regular use (30 or more pills per month for 5 or more years) of NSAIDs was associated with reduced risk of prostate cancer (RR = 0.82, 95% CI = 0.71 to 0.94). Long-duration regular use of aspirin was also associated with reduced risk of prostate cancer (RR = 0.85, 95% CI = 0.73 to 0.99). The absolute rate of prostate cancer (standardized to the age distribution of study participants using 5-year age categories) was 1013 per 100,000 person-years among men who had never reported NSAID use, and 847 per 100,000 person-years among long duration regular NSAID users.


CONCLUSIONS
These results support the hypothesis that long duration regular NSAID use is associated with modestly reduced risk of prostate cancer.
Epidemiology and Surveillance Research, American Cancer Society, National Home Office, 1599 Clifton Rd., NE, Atlanta, GA 30329, USA. eric.jacobs@cancer.org
Eric J
EJ
Jacobs
Carmen
C
Rodriguez
Alison M
AM
Mondul
Cari J
CJ
Connell
S Jane
SJ
Henley
Eugenia E
EE
Calle
Michael J
MJ
Thun
D000368:Aged; D000369:Aged, 80 and over; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000008:administration & dosage*; D001241:Aspirin / Q000008:administration & dosage*; D015331:Cohort Studies; D016001:Confidence Intervals; D015986:Confounding Factors, Epidemiologic; D004334:Drug Administration Schedule; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011446:Prospective Studies; D011471:Prostatic Neoplasms / Q000453:epidemiology* / Q000208:ethnology / Q000517:prevention & control*; D018570:Risk Assessment; D012307:Risk Factors; D011795:Surveys and Questionnaires; D014481:United States / Q000453:epidemiology
D000894:Anti-Inflammatory Agents, Non-Steroidal; D001241:Aspirin