Table 1.

Characteristics of studies included in the meta-analysis of aspirin and NSAIDs and risk of pancreatic cancer, ordered by exposure and year of publication

Study and countryStudy designCasesControls or cohort sizeExposureExposure definitionRR (95% CI)Adjustments
Schreinemachers and Everson (12); United StatesCohort3012,668AspirinAny use of aspirin in the last 30 days0.67 (0.33-1.36)Age, sex
Anderson et al. (13); United StatesCohort8028,283AspirinAny use vs no use0.58 (0.36-0.90)Age, smoking, diabetes, multivitamin use
≥6 times/wk0.40 (0.20-0.82)
Menezes et al. (14); United StatesHospital-based case-control194582Aspirin≥1 tablet/wk for >6 mo1.00 (0.72-1.39)Age, smoking, family history of pancreatic cancer
≥7 tablets/wk0.85 (0.49-1.45)
>10 y1.21 (0.81-1.82)
Friis et al. (15); DenmarkCohort6229,470AspirinPrescriptions of low-dose (75-150 mg) aspirin1.10 (0.80-1.30)Age, sex
Schernhammer et al. (16); United StatesCohort16188,378Aspirin≥2 tablets/wk1.20 (0.87-1.65)Age, smoking, BMI, physical activity, diabetes
≥7 tablets/wk1.30 (0.70-2.40)*
>20 y and ≥2 tablets/wk1.58 (1.03-2.43)
Jacobs et al. (17); United StatesCohort4,577 (deaths)987,590AspirinAny use vs no use0.96 (0.92-1.01)Age, sex, race, smoking, BMI, diabetes
>7 times/wk0.97 (0.86-1.09)
≥20 y and >7 times/wk0.96 (0.69-1.33)
Ratnasinghe et al. (18); United StatesCohort78 (deaths)22,834AspirinAny use vs no use0.87 (0.42-1.77)Age, sex, race, poverty index, education, BMI
Cook et al. (22); United StatesRandomized trial5139,876AspirinLow-dose (100 mg) aspirin every other day for 10 y vs placebo1.42 (0.81-2.49)None
Anderson et al. (13); United StatesCohort8028,283NA-NSAIDsAny use vs no use1.19 (0.76-1.88)Age, smoking, diabetes, multivitamin use
≥6 times/wk1.28 (0.68-2.43)
Sørensen et al. (21); DenmarkCohort149172,057NA-NSAIDsAny prescription1.10 (0.90-1.20)Age, sex
≥10 prescriptions0.90 (0.60-1.30)
Coogan et al. (19); United StatesHospital-based case-control4915,833NSAIDs≥4 d/wk for ≥3 mo0.80 (0.50-1.10)Age, sex, education smoking, family history of digestive cancer, other
Langman et al. (20); United StatesPopulation-based case-control5131,535NSAIDsAny prescription1.15 (0.88-1.49)Age, smoking
≥7 prescriptions during mo 13-36 before index date1.49 (1.02-2.18)
  • Abbreviations: NA-NSAIDs, nonaspirin NSAIDs; BMI, body mass index.

  • * The RR (and its 95% CI) was derived by pooling the RRs for categories 7 to 13 and ≥14 tablets per week.

  • Randomized 2 × 2 factorial trial evaluating the effects of low-dose aspirin (100 mg every other day) and vitamin E (600 IU every other day) in the primary prevention of cardiovascular disease and cancer.

  • The RR (and its 95% CI) was derived by pooling the RRs for 1, 1 to 6, and ≥7 prescriptions during months 13 to 36 before index date.