Table 3.

Preoperative severity of joint problems (OHS in hip replacement and OKS in knee replacement) and likelihood of long-standing problems by the number of chronic diseases (95% CI, P-value for trend) (adjusted according to age, sex, ethnicity and SES)

Count of chronic diseases	Severity of joint problems (0 worse and 48 best)			Functional status (0 worst 24 best)			Pain (0 worst 24 best)			Long-standing joint problems (duration > 5 years pre-operatively)
	Mean score	Adjusted difference (95% CI)	P-value	Mean score	Adjusted difference (95% CI)	P-value	Mean score	Adjusted difference (95% CI)	P-value	%	Adjusted OR (95% CI)	P-value
Hip replacement:OHS
0	18.8	Reference		10.6	Reference		8.21	Reference		21.3	Reference
1	17.4	−1.45 (−1.52, −1.38)	< 0.001	9.73	−0.79 (−0.83, − 0.76)	< 0.001	7.67	− 0.66 (− 0.69, − 0.62)	< 0.001	17.3	0.93 (0.91, 0.95)	0.076
2	16.2	−2.79 (− 2.87, − 2.70)		9.03	−1.52 (− 1.56, − 1.47)		7.17	−1.28 (− 1.32, − 1.23)		16.5	0.98 (0.95, 1.00)
3	14.9	−4.15 (− 4.27, − 4.04)		8.31	− 2.23 (− 2.30, − 2.17)		6.58	− 1.92 (− 1.98, − 1.86)		16.1	1.02 (0.98, 1.06)
4+	13.3	−5.79 (− 5.96, − 5.61)		7.42	− 3.13 (− 3.23, − 3.03)		5.89	− 2.66 (− 2.75, − 2.56)		17.5	1.15 (1.09, 1.23)
Knee replacement:OKS
0	19.5	Reference		12.5	Reference		7.01	Reference		45.7	Reference
1	18.5	−1.06 (−1.12, −0.99)	< 0.001	11.7	−0.72 (− 0.76, − 0.68)	< 0.001	6.77	−0.34 (− 0.37, − 0.31)	< 0.001	42.2	0.95 (0.93, 0.97)	0.663
2	17.6	−2.16 (− 2.24, − 2.09)		11.0	−1.50 (− 1.51, − 1.42)		6.51	− 0.70 (− 0.73, − 0.67)		41.9	0.97 (0.95, 0.99)
3	16.5	−3.38 (− 3.48, − 3.28)		10.3	−2.28 (− 2.34, − 2.22)		6.17	− 1.10 (− 1.15, − 1.06)		41.8	0.98 (0.96, 1.01)
4+	15.1	−4.79 (− 4.94, − 4.64)		9.39	−3.21 (− 3.31, − 3.11)		5.75	− 1.58 (− 1.64, − 1.51)		41.9	0.99 (0.95, 1.04)