Table 4.

OR and 95% CI values of total prostate cancer stratified by aspirin use since age 20 years in 691 matched pairs nested in the Health Professionals Follow-up Study, 1993 to 2000

T. vaginalis antibody seronegative
T. vaginalis antibody seropositive
Cases/controlsOR (95% CI)Cases/controlsOR (95% CI)*Multivariable-adjusted OR (95% CI)*,
Aspirin use since age 20 y
    Infrequent use (0-19% of the time)154/1481.0032/152.00 (1.02-3.89)2.05 (1.05-4.02)
    Moderate use (20-79% of the time)181/2011.0023/191.33 (0.70-2.55)1.37 (0.71-2.62)
    Regular use (80-100% of the time)241/2431.0029/271.03 (0.59-1.80)1.05 (0.60-1.85)§
  • * Estimated by unconditional logistic regression, including terms for T. vaginalis antibody serostatus, age, time of day, season and year of blood draw, and PSA screening history before blood draw.

  • Adjusted for race (Caucasian, non-Caucasian) and cumulative family history of prostate cancer through 1996.

  • Percentage of years that aspirin was used with any frequency.

  • § P values for interaction with aspirin use = 0.11.