. Author manuscript; available in PMC: 2021 Jul 16.

Published in final edited form as: J Bone Miner Res. 2020 Feb 5;35(4):631–640. doi: 10.1002/jbmr.3935

Table 2.

Incident Hip Fracture Within One Year Among Patients Initiating Tramadol Comparing with Initiation of another Commonly Used Weak Opioid (Codeine)

	Weak opioid
	Tramadol vs. Codeine
Participants (n)	146,956	146,956
Incident hip fracture (n)	518	401
Mean follow-up (years)	0.95	0.94
Rate (/1000 person-years)^*	3.7	2.9
RD (/1000 person-years, 95% CI)	0.8 (0.4, 1.2)	0.0 (reference)

n, number; RD, rate difference; 95% CI, 95% confidence interval.

Number (rate) of competing event (i.e., death) in tramadol and codeine group was 5,449 (39.2/1000 person-years) and 4,984 (36.0/1000 person-years), respectively.