Table 2

Unadjusted and adjusted parameter estimates for Western Ontario and McMaster Universities Osteoarthritis Index pain and physical function scores 12 months postoperatively

Variable	Pain				Physical function

	Crude β (95% CI)	p value	Adjusted β (95%_CI)	p value	Crude β (95% CI)	p value	Adjusted β (95%_CI)	p value
Sex		0.3		0.99		0.1		0.6

Female	1 (reference)		1 (reference)		1 (reference)		1 (reference)

Male	1.2 (−0.9 to 3.3)		−0.1 (−2.0 to 2.0)		1.6 (−0.4 to 3.6)		0.6 (−1.4 to 2.5)

Age	0.2 (0.1 to 0.3)	0.003	0.1 (−0.1 to 0.2)	0.08	0.1 (−0.1 to 0.1)	0.8	0.1 (−0.1 to 0.1)	0.8

Preoperative WOMAC score	0.4 (0.3 to 0.4)	< 0.001	0.3 (0.3 to 0.4)	< 0.001	0.4 (0.4 to 0.5)	< 0.001	0.4 (0.3 to 0.4)	< 0.001

Preoperative opioid use

Opioid-naive	1 (reference)		1 (reference)		1 (reference)		1 (reference)

Intermittent	−6.4 (−8.7 to −4.1)	< 0.001	−4.3 (−6.6 to −2.1)	< 0.001	−7.0 (−9.3 to −4.8)	< 0.001	−5.2 (−7.4 to −3.1)	< 0.001

Long-term	−11.4 (−15.4 to −7.3)	< 0.001	−7.7 (−11.6 to −3.7)	< 0.001	−11.3 (−15.2 to −7.4)	< 0.001	−7.8 (−11.6 to −4.0)	<_ 0.001

Comorbidities

Depression	−5.2 (−7.9 to −2.4)	< 0.001	−2.6 (−5.3 to 0.1)	0.06	−5.5 (−8.0 to −2.7)	< 0.001	−2.8 (−5.3 to −0.3)	0.03

Diabetes	−5.4 (−7.8 to −2.9)	< 0.001	−3.7 (−6.0 to −1.3)	0.002	−4.5 (−6.8 to −2.0)	< 0.001	−2.5 (−4.8 to −0.2)	0.03

Cardiac disease	−3.2 (−5.5 to −0.8)	0.008	−2.3 (−4.7 to −0.1)	0.048	−3.9 (−6.2 to −1.6)	0.001	−2.2 (−4.4 to 0.1)	0.06

Liver disease	−9.2 (−18.6 to 0.1)	0.05	−8.0 (−16.9 to 0.9)	0.08	−6.5 (−15.5 to 2.6)	0.2	—	—

Pulmonary disease	−4.6 (−8.1 to −1.1)	0.01	−3.3 (−6.7 to 0.1)	0.05	−5.3 (−8.7 to −1.9)	0.002	−2.9 (−6.2 to 0.3)	0.08

Obesity	−2.1 (−4.3 to 0.2)	0.07	—	—	−2.2 (−4.4 to −0.1)	0.04	—	—

Stroke	−2.9 (−11.2 to 5.5)	0.5	—	—	−3.6 (−11.6 to 4.5)	0.4	—	—

Renal disease	−3.9 (−10.3 to 2.5)	0.2	—	—	−4.7 (−10.8 to 1.5)	0.1	—	—

CI = confidence interval; WOMAC = Western Ontario and McMaster Universities Osteoarthritis Index.