Table 2.

Univariate and multivariate Cox’s proportional hazard ratio analysis of risk factors of reoperation for recurrence

Variable	Reoperation rate		Univariate analysis		Multivariate analysis*
	(n)	(%)	Hazard ratio	P	Hazard ratio	P
Age, years
< 59	207/6919	3.0	1.00 (reference)		1.00 (reference)
≥ 59	284/6920	4.1	1.41 (1.18–1.69)	< 0.001	1.33 (1.10–1.60)	0.003
ASA class
I–II	459/13,068	3.5	1.00 (reference)		1.00 (reference)
III–IV	32/747	4.3	1.33 (0.93–1.91)	0.116	1.20 (0.84–1.73)	0.320
Sex
Male	467/12,148	3.8	1.00 (reference)
Female	24/1691	1.4	0.39 (0.26–0.59)	< 0.001
Type of mesh
HWM	235/7449	3.2	1.00 (reference)		1.00 (reference)
LWM	256/6390	4.0	1.44 (1.21–1.72)	< 0.001	1.56 (1.29–1.88)	< 0.001
Type of hernia
Unilateral	190/5474	3.5	1.00 (reference)
Bilateral	301/8365	3.6	1.00 (0.84–1.20)	0.985
Type of defect
Direct	218/5710	3.8	1.00 (reference)		1.00 (reference)
Indirect	211/6265	3.4	0.91 (0.75–1.10)	0.308	0.96 (0.79–1.18)	0.722
Femoral	27/808	3.3	0.92 (0.62–1.37)	0.682	1.36 (0.89–2.08)	0.158
Combined/others	35/1056	3.3	0.89 (0.62–1.27)	0.519	0.86 (0.60–1.23)	0.406
Size of defect
< 1.5 cm	82/2694	3.0	1.00 (reference)		1.00 (reference)
1.5–3 cm	278/8006	3.5	1.12 (0.88–1.43)	0.367	1.01 (0.79–1.31)	0.911
> 3 cm	119/2748	4.3	1.40 (1.06–1.86)	0.019	1.27 (0.94–1.71)	0.124
Recurrent hernia
No	387/11,090	3.5	1.00 (reference)		1.00 (reference)
Yes	104/2749	3.8	1.07 (0.86–1.33)	0.544	0.95 (0.75–1.21)	0.680
Mesh fixation
No	170/5169	3.3	1.00 (reference)		1.00 (reference)
Yes	321/8670	3.7	1.12 (0.93–1.35)	0.221	1.01 (0.83–1.22)	0.960

Values in parentheses are 95% confidence intervals. Age is divided by median

Significant P values are in bold face

ASA class American Society of Anesthesiologists classification

*Stratified for sex and type of hernia in the multivariate analysis