The Potential Value of Systemic Inflammation Response Index on Delirium After Hip Arthroplasty Surgery in Older Patients: A Retrospective Study

Figures & data

Table 1 Baseline Characteristics and Inflammatory Parameters of the Study Population

Characteristics	POD Group (n=34)	Non-POD Group (n=82)	P
Age (y), mean ± SD	74.53±7.47	72.67±5.60	0.198
Male, n (%)	18 (52.9)	44 (53.7)	0.944
BMI (kg/m^2), mean ± SD	24.44±2.29	24.43±2.69	0.978
ASA (I/II/III)	10/19/5	19/58/5	0.198
MMSE scores
Preoperative, mean ± SD	27.26±1.68	27.15±1.59	0.720
Postoperative 24 h, mean ± SD	25.50±1.80	26.81±1.60	<0.001
Postoperative 72 h, mean ± SD	25.09±2.62	27.50±1.60	<0.001
Education (y), mean ± SD	8.12±3.13	7.93±2.93	0.755
Operation duration (h), mean ± SD	1.61±0.62	1.66±0.68	0.723
Diabetes, n (%)	14 (41.2)	40 (48.8)	0.455
Hypertension, n (%)	6 (17.6)	16 (19.5)	0.816
Hyperlipidemia, n (%)	5 (14.7)	7 (8.5)	0.321
Heart disease, n (%)	6 (17.6)	11 (13.4)	0.557
SIRI (10^9), median (IQR)	1.43 (1.13–3.18)	0.87 (0.63–1.22)	<0.001
NLR, median (IQR)	3.06 (1.91–5.50)	2.09 (1.54–2.89)	0.002
PLR, median (IQR)	121 (92–168)	114 (88–152)	0.387

Abbreviations: POD, postoperative delirium; BMI, body mass index; ASA, American Society of Anesthesiologists; MMSE, Mini-Mental State Examination; SIRI, systemic inflammation response index; NLR, neutrophil-to-lymphocyte ratio; PLR, platelet-to-lymphocyte ratio; SD, standard deviation; IQR, interquartile range.

Figure 1 The violin plots demonstrating the differences in the distribution of the SIRI levels between Non-POD and POD groups.

Abbreviations: SIRI, systemic inflammation response index; POD, postoperative delirium.

Table 2 Univariate and Multivariate Logistic Regression Analysis Showing the Independent Predictors of POD

	Univariate		Multivariate
	OR (95% CI)	P	OR (95% CI)	P
Age	1.05 (0.98–1.12)	0.146	1.00 (0.92–1.09)	0.987
Gender	0.97 (0.44–2.17)	0.944	1.08 (0.42–2.82)	0.868
BMI	1.01 (0.86–1.17)	0.978	1.02 (0.84–1.25)	0.814
ASA II	0.62 (0.25–1.57)	0.315	0.75 (0.25–2.25)	0.608
ASA III	1.90 (0.44–8.16)	0.388	2.04 (0.35–11.98)	0.432
Preoperative MMSE scores	1.05 (0.81–1.35)	0.717	1.24 (0.90–1.71)	0.195
Education	1.02 (0.89–1.17)	0.752	1.03 (0.87–1.22)	0.729
Operation duration	0.89 (0.48–1.66)	0.720	1.05 (0.51–2.17)	0.886
SIRI	2.58 (1.56–4.26)	< 0.001	3.04 (1.16–7.95)	0.023
NLR	1.43 (1.15–1.79)	0.001	1.03 (0.59–1.78)	0.926
PLR	1.01 (0.99–1.02)	0.598	0.99 (0.98–1.01)	0.317

Abbreviations: POD, postoperative delirium; BMI, body mass index; MMSE, Mini-Mental State Examination; SIRI, systemic inflammation response index; NLR, neutrophil-to-lymphocyte ratio; PLR, platelet-to-lymphocyte ratio; OR, odds ratio; CI, confidence interval.

Figure 2 Receiver operating characteristic (ROC) curve for inflammatory parameters as a predictor of POD.

Abbreviations: SIRI, systemic inflammation response index; NLR, neutrophil-to-lymphocyte ratio; PLR, platelet-to-lymphocyte ratio.