Long-term health related quality of life in total knee arthroplasty

Table 5 Factors associated jointly with change in WOMAC at 10 years exceeding minimal clinically important difference: multivariable analysis

Factors	Change in WOMAC exceeding MCID^*
	Pain			Stiffness		Function
	Odds ratio^** (95% CI)	p value	Odds ratio (95% CI)		p value	Odds ratio (95% CI)	p value
Baseline WOMAC	1.06 (1.04–1.08)	< 0.001	1.07 (1.06–1.09)		< 0.001	1.06 (1.04–1.08)	< 0.001
Age (continuous)						0.94 (0.90–0.97)	0.001
BMI categorized
BMI < 25			-ref-		-ref-	-ref-	-ref-
25 ≤ BMI < 30			0.19 (0.05–0.66)		0.009	0.52 (0.21–1.29)	0.159
30 ≤ BMI < 35			0.18 (0.05–0.66)		0.009	0.35 (0.14–0.88)	0.026
BMI ≥ 35			0.20 (0.05–0.79)		0.022	0.25 (0.08–0.74)	0.012
Comorbidity
Peripheral vascular disease						0.49 (0.24–0.99)	0.048
Depression	0.42 (0.18–0.94)	0.036	0.26 (0.09–0.77)		0.015	0.19 (0.06–0.56)	0.003
Rheumatologic disease	0.37 (0.17–0.80)	0.011
Readmissions (6 months)						0.41 (0.18–0.94)	0.035
Complications from hospital discharge			0.31 (0.11–0.91)		0.032
Rehabilitation from hospital discharge			2.12 (1.18–3.80)		0.012
AUC (95%CI)	0.74 (0.69–0.79)			0.85 (0.81–0.89)		0.78 (0.73–0.82)

Abreviations: BMI, Body Mass Index; WOMAC, Westen Ontario and McMaster Universities Osteoarthritis Index (0, best; 100, worst); CI, Confidence interval; MCID, Minimal clinically important difference; AUC: Area under the ROC curve; ref: reference group
^*Changes in WOMAC exceeding the cut-offs points of the MCID (Pain = 29.88; Stiffness = 26.76; Function = 32.72)
^**An Odds ratio < 1 indicates a lower likelihood of exceeding minimal clinically important difference; an Odds ratio > 1 indicates a higher likelihood of exceeding minimal clinically important difference
These models have been adjusted for age and gender and they only appear in the table if some of them were statistically significant

ISSN: 1471-2474