Modified Frailty Index Independently Predicts Postoperative Pulmonary Infection in Elderly Patients Undergoing Radical Gastrectomy for Gastric Cancer

Figures & data

Table 1 Demographics and Clinical Characteristics Associated with Pulmonary Infection in Elderly GC Patients After Radical Gastrectomy

Variables	Pulmonary Infection		P-value
	Yes (n = 51)	No (n = 295)
Age (year)	75.1±3.8	73.5±3.2	0.002*
Gender, n (%)	–	–	0.443
Male	37 (72.5)	198 (67.1)	–
Female	14 (27.5)	97 (32.9)	–
BMI (kg/m^2)	22.2±2.1	21.9±2.0	0.327
ASA physical status, n (%)	–	–	0.017*
II	22 (43.1)	180 (61.0)	–
III	29 (56.9)	115 (39.0)	–
Current smoker, n (%)	17 (33.3)	60 (20.3)	0.039*
Type of operation, n (%)	–	–	0.891
Total gastrectomy	13 (25.5)	64 (21.7)	–
Proximal gastrectomy	6(11.8)	38(12.9)	–
Distal gastrectomy	26(51.0)	149(50.5)	–
Pylorus–preserving gastrectomy	6(11.8)	44(14.9)	–
Reconstruction method, n (%)	–	–	0.655
Billroth I	16(31.4)	93(31.5)	–
Billroth II	6(11.8)	20(6.8)	–
Roux–en–Y	17(33.3)	109(36.9)	–
Gastroesophageal	12(23.5)	73(24.7)	–
Surgical approach, n (%)	–	–	0.016*
Laparotomy	16 (31.4)	50 (16.9)	–
Laparoscopic	35 (68.6)	245 (83.1)	–
Extent of lymph node dissection, n (%)	–	–	0.469
≥D2	27 (52.9)	140 (47.5)	–
<D2	24 (47.1)	155 (52.5)	–
Duration of operation (min)	228.3±37.1	215.6±33.5	0.014*
Estimated blood loss (mL)	420.1±144.8	406.9±152.5	0.566
Histopathological grade, n (%)	–	–	0.793
G1–2	31 (60.8)	206 (69.8)	–
G3–4	20 (39.2)	89 (30.2)	–
Pathological stage, n (%)	–	–	0.597
I/II	30 (58.8)	185 (62.7)	–
III/IV	21 (41.2)	110 (37.3)	–
Intra–operative blood transfusion, n (%)	–	–	0.020*
Yes	11 (21.6)	30 (10.2)	–
No	40 (78.4)	265 (89.8)	–
Duration of prophylactic antibiotics (d)	3.6±0.4	3.5±0.4	0.100
ICU admission, n (%)	–	–	0.280
Yes	22 (43.1)	104 (35.3)	–
No	29 (56.9)	191 (64.7)	–
Oesophageal reflux, n (%)	7(13.7)	30(10.2)	0.448
NLR	2.57±0.48	2.46±0.51	0.152
CONUT score, n (%)	–	–	0.023*
< 4	43(84.3)	276(93.6)	–
≥3	8(15.7)	19(6.4)	–
mFI score, n (%)	–	–	<0.001
≥0.225	20(39.2)	33(11.2)	–
< 0.225	31(60.8)	262(88.8)	–

Note: *P value <0.05 by Chi-square test, t-test or Mann Whitney U-test.

Abbreviations: GC, gastric cancer; ASA, American Society of Anesthesiologists; BMI, body mass index; ICU, intensive care unit; NLR, neutrophil–lymphocyte ratio; CONUT, controlling nutrition status; mFI, modified frailty index.

Figure 1 The flow chart.

Abbreviation: GC, gastric cancer.

Figure 2 Percentage of positive items of mFI in total patients.

Abbreviations: mFI, modified frailty index; COPD, chronic obstructive pulmonary disease; PCI, percutaneous coronary intervention.

Table 2 Preoperative Laboratory Variables Associated with Pulmonary Infection in Elderly GC Patients After Radical Gastrectomy

Variables	Pulmonary Infection		P-value
	Yes (n = 51)	No (n = 295)
Hemoglobin (g/dL)	–	–	0.595
≥11.0	33 (64.7)	202 (68.5)	–
<11.0	18 (35.3)	93 (31.5)	–
White blood cell (×10^9/L)	–	–	0.230
4–10	40 (78.4)	251 (85.1)	–
<4 or >10	11 (21.6)	44 (14.9)	–
Albumin (mg/dL)	–	–	0.016*
≥35.0	39 (76.5)	262 (88.8)	–
<35.0	12 (23.5)	33 (11.2)	–
Creatinine (µmol/L)	–	–	0.418
<133.0	48 (94.1)	285 (96.6)	–
≥133.0	3 (5.9)	10 (3.4)	–
Urea (mmol/L)	–	–	0.599
<7.1	41 (80.4)	246 (83.4)	–
≥7.1	10 (19.6)	49 (16.6)	–
CRP (mg/L)	–	–	0.012*
<8.0	40 (78.4)	267 (90.5)	–
≥8.0	11 (21.6)	28 (9.5)	–
TNF–α (pg/mL)	–	–	0.395
<8.1	45 (88.2)	271 (91.9)	–
≥8.1	6 (11.8)	24 (8.1)	–

Note: *P value<0.05 by Chi-square test, or Fisher exact test.

Abbreviations: GC, gastric cancer; CRP, C-reactive protein; TNF-α, tumor necrosis factor-α.

Figure 3 Predictive values of factors for pulmonary infection in elderly GC patients by ROC curve analysis. (A) age; (B) duration of operation; (C) mFI; (D) albumin; and (E) CRP.

Abbreviations: GC, gastric cancer; ROC, receiver operating characteristic; mFI, modified frailty index; AUC, area under the curve; CRP, C-reactive protein.

Figure 4 Forest plot of the univariate logistic regression analysis for pulmonary infection.

Abbreviations: ASA, American Society of Anesthesiologists; NLR, neutrophil–lymphocyte ratio; CONUT, controlling nutrition status; mFI, modified frailty index; CRP, C-reactive protein; OR, odds ratio; CI, confidence interval.

Figure 5 Forest plot of the multivariate logistic regression analysis for pulmonary infection.

Abbreviations: ASA, American Society of Anesthesiologists; mFI, modified frailty index; CRP, C-reactive protein; OR, odds ratio; CI, confidence interval.