TABLE 2.

Recurrence‐free survival for 6945 patients operated on for colorectal cancer between 2007 and 2012 in 21 hospitals in Sweden, where the exposed patients were operated on at hospitals that used NSAIDs in their postoperative analgesia protocols

Tumour site	No. of NSAID‐exposed/total no. of patients (%)	Unadjusted HR (95% CI)	Adjusted a HR (95% CI)
All colorectal cancers	3996/6945 (57.5%)	0.96 (0.86–1.06)	0.97 (0.87–1.09)
Right‐sided colon cancer	1547/2667 (58.0%)	0.97 (0.84–1.12)	0.98 (0.85–1.14)
Left‐sided colon cancer	1323/2294 (57.7%)	0.95 (0.81–1.11)	0.99 (0.84–1.16)
Rectal cancer	1126/1982 (56.8%)	0.94 (0.80–1.11)	0.94 (0.80–1.12)

Abbreviations: CI, confidence interval; HR, hazard ratio; NSAID, nonsteroidal anti‐inflammatory drug.

Cox regression modelling was used to derive HRs with 95% CIs.

^a With adjustment for American Society of Anesthesiologists class, age, body mass index, intraoperative bleeding, diverting stoma, hospital volume, neoadjuvant therapy, emergency procedure, sex, tumour location, year of surgery and clinical tumour stage.