Table 2

Crude and adjusted relative risks (RRs) and associated 95% CIs of colorectal cancer comparing new users with non-users of low-dose aspirin by cancer location, stage at diagnosis, and time elapsed since index date*, Denmark 2005–2013

Colorectal cancer1–3 years3–5 years5+ years
Crude RR
(95% CI)		Adjusted RR†
(95% CI)		Crude RR
(95% CI)		Adjusted RR†
(95% CI)		Crude RR
(95% CI)		Adjusted RR†
(95% CI)
All1.00 (0.94 to 1.06)1.00 (0.93 to 1.06)0.95 (0.88 to 1.02)0.90 (0.83 to 0.98)1.00 (0.92 to 1.09)0.91 (0.82 to 1.00)
 Location      
  Proximal colon1.09 (0.98 to 1.20)1.04 (0.93 to 1.17)0.96 (0.84 to 1.09)0.89 (0.77 to 1.03)1.05 (0.91 to 1.21)0.93 (0.79 to 1.10)
  Distal colon1.04 (0.93 to 1.15)1.01 (0.89 to 1.14)0.97 (0.85 to 1.11)0.90 (0.77 to 1.06)1.01 (0.86 to 1.18)0.93 (0.77 to 1.13)
  Rectum0.90 (0.81 to 1.00)0.94 (0.83 to 1.06)0.91 (0.80 to 1.03)0.87 (0.76 to 1.01)0.97 (0.83 to 1.12)0.91 (0.76 to 1.08)
 Stage at diagnosis      
  Localised1.09 (0.98 to 1.21)1.03 (0.92 to 1.16)1.07 (0.94 to 1.22)0.97 (0.84 to 1.12)1.08 (0.93 to 1.25)0.98 (0.82 to 1.17)
  Regional0.92 (0.81 to 1.04)0.94 (0.81 to 1.08)0.83 (0.71 to 0.97)0.83 (0.69 to 0.99)0.99 (0.82 to 1.19)0.92 (0.73 to 1.15)
  Metastatic0.94 (0.84 to 1.06)0.99 (0.86 to 1.12)0.90 (0.78 to 1.04)0.92 (0.78 to 1.09)0.90 (0.75 to 1.07)0.85 (0.69 to 1.04)
  Unknown1.04 (0.91 to 1.19)1.04 (0.90 to 1.19)0.97 (0.83 to 1.14)0.85 (0.71 to 1.02)1.01 (0.85 to 1.20)0.87 (0.71 to 1.06)

  • *Date of first-time prescription for low-dose aspirin.

  • †Adjusted for index year, Charlson Comorbidity Index score, alcoholism-related disorders, chronic liver disease, chronic obstructive pulmonary disease, diverticular disease, diabetes mellitus and prescriptions for other medications (including NSAIDs, hormone replacement therapy, statins, oral antidiabetic drugs, insulin and ACE inhibitors) redeemed within 1 year prior to the index date.

  • NSAIDs, non-steroidal anti-inflammatory drugs.