Total Psoas Area Index is Valuable to Assess Sarcopenia, Sarcopenic Overweight/Obesity and Predict Outcomes in Patients Undergoing Open Pancreatoduodenectomy

Figures & data

Figure 1 Flowchart of the study.

Figure 2 Computed tomographic images at the the middle third lumbar vertebral level. (A) Sagittal map. (B) Cross-sectional image and red circle shows the outline of psoas.

Table 1 Demographic and Clinical Data

	All (n=152)	Male (n=89)	Female (n=63)	p^#
Age, years	63.2±11.6	62.7±10.8	63.8±12.6	0.565
BMI, kg/m^2	23.5±3.5	23.5±2.8	23.4±4.4	0.894
Comorbidities, n(%)
Diabetes	36 (23.7)	19 (21.3)	17 (27.0)	0.421
Hypertension	55 (36.2)	34 (38.2)	21 (33.3)	0.538
Cardiovascular disease	12 (7.9)	6 (6.7)	6 (9.5)	0.531
Smoking	59 (38.8)	56 (62.9)	3 (4.8)	0.000
Drinking	44 (28.9)	43 (48.3)	1 (1.6)	0.000
Jaundice	75 (49.3)	46 (51.7)	29 (46.0)	0.492
Nutrition status, n(%)
NRS2002≥3	106 (69.7)	59 (66.3)	47 (74.6)	0.272
GLIM-defined malnutrition	86 (56.6)	47 (52.8)	39 (61.9)	0.265
Diagnosis, n(%)
Malignance	123 (80.9)	73 (82.0)	50 (79.4)	0.706
PDAC	43 (28.3)	20 (22.7)	23 (36.5)	0.064
Lab results
Hemoglobin, g/L	122.1±16.0	126.6±16.9	116.0±12.3	0.000
Albumin, g/L	38.1±4.7	38.1±5.0	38.0±4.3	0.851
Lymphocyte, ×10^9	2.27±9.41	2.77±12.3	1.58±0.56	0.444
Operation data
Operation time, min	356.3±84.4	358.6±88.6	353.0±78.5	0.689
Intraoperative hemorrhage, mL	682.2±806.8	774.4±966.5	550.8±475.4	0.097
Duct-mucous anastomosis, n(%)	103 (67.8)	59 (66.3)	44 (69.8)	0.645
Pancreatic duct diameter, cm	3.10±2.12	2.75±1.92	3.59±2.20	0.175
CT characters
Preoperative TPA, cm^2	13.4±5.0	16.0±4.5	9.7±3.0	0.000
Preoperative TPAI, cm^2/m^2	4.81±1.59	5.47±1.53	3.88±1.17	0.000
Preoperative PMD, HU	50.6±8.7	51.2±8.0	49.8±9.6	0.356
Postoperative TPA, cm^2	11.4±4.3*	13.7±3.9	8.4±2.7	0.000
Postoperative TPAI, cm^2/m^2	4.12±1.39*	4.69±1.34	3.36±1.04	0.000
Postoperative PMD, HU	46.2±8.6*	47.8±7.9	43.9±9.1	0.010
TPAI-defined sarcopenia, n(%)	59 (38.8)	31 (34.8)	28 (44.4)	0.231
Sarcopenic overweight/obesity, n(%)	26 (17.1)	14 (15.7)	12 (19.0)	0.950
Outcomes
Major complications, n(%)	31 (20.4)	23 (25.8)	8 (12.7)	0.048
Re-operation, n(%)	14 (9.2)	12 (13.5)	2 (3.2)	0.030
In-hospital mortality, n(%)	5 (3.3)	5 (5.6)	-	-
LOS, day	27.7±18.4	28.3±19.3	27.0±17.2	0.681
Total hospital cost, USD	19,414.5±8349.0	20,834.1±9353.8	16,957.5±5593.1	0.032

Notes: ^#P-value of the comparison between two genders. *P-values of the analysis between preoperative and postoperative CT measurements, all three P-values <0.01.

Abbreviations: BMI, body mass index; NRS, nutritional risk screening; GLIM, global leadership initiative malnutrition; PDAC, pancreatic ductal adenocarcinoma; CT, computed tomography; TPA, total psoas area; TPAI, total psoas area index; PMD, psoas muscle density; HU, Hounsfield units; LOS, length of stay; USD, United States Dollar.

Figure 3 Receiver operating characteristic curves of TPAI for major complications. (A) For males. (B) For females.

Table 2 Estimation of the Cutoff Values of TPAI

	Male (n =89)	Female (n =63)
Major complication, n (%)	23 (25.8)	8 (12.7)
Estimated cut-off value in TPAI, cm^2/m^2	4.78	3.46
Area under the ROC curve	0.779, 95% CI (0.674, 0.885)	0.780, 95% CI (0.639, 0.920)
Sensitivity	0.739	0.875
Specificity	0.788	0.618
Youden Index	0.527	0.493
p-value	0.000	0.011

Abbreviations: TPAI, total psoas area index; ROC, receiver operating characteristic.

Table 3 Comparison of Outcomes in Different Sarcopenic Cohorts

	Total, n = 152					Male, n = 89			Female, n = 63
	Sarcopenia (n = 59)	Sarcopenic Overweight/Obesity (n=26)	Normal (n = 93)	P*	P^#	TPAI ≤4.78 (n = 31)	TPAI>4.78 (n = 58)	P	TPAI ≤3.46 (n = 28)	TPAI>3.46 (n = 35)	P
Major complications, n(%)	24 (40.7)	11 (42.3)	7 (7.5)	0.000	0.000	17 (54.8)	6 (10.3)	0.000	7 (25.0)	1 (2.9)	0.025
Re-operation, n(%)	11 (18.6)	5 (19.2)	3 (3.2)	0.001	0.015	9 (29.0)	3 (5.2)	0.005	2 (7.1)	0 (0.0)	0.337
In-hospital mortality, n(%)	4 (6.8)	1 (3.8)	1 (1.1)	0.055	0.378	4 (12.9)	1 (1.7)	0.048	–	–	–
LOS, days	33.4±21.2	32.2±15.1	24.1±15.4	0.004	0.019	36.6±24.0	23.8±14.6	0.001	29.9±17.4	24.6±16.9	0.232
Total hospital cost, USD	22,761.8± 9158.5	25,190.5±7095.6	16,668.0± 6542.3	0.003	0.000	25,445.6± 9710.1	17,144.8± 7339.0	0.002	18,288.5± 6212.9	15,816.5± 4845.6	0.270

Notes: *Comparison between sarcopenia and normal groups. ^#Comparison between sarcopenic overweight/obesity and normal groups.

Abbreviations: TPAI, total psoas area index; LOS, length of stay; USD, United States Dollar.

Table 4 Association Between Different Covariates and Rate of Major Complications

	Univariate		Multivariate
	OR (95% CI)	p	OR (95% CI)	p
Age, year	1.013 (0.978, 1.049)	0.476
BMI, kg/m^2	1.077 (0.967, 1.199)	0.178
Comorbidity of diabetes	1.740 (0.730, 4.149)	0.212
Comorbidity of jaundice	1.555 (0.700, 3.452)	0.278
Diagnosis of pancreatic cancer	0.681 (0.269, 1.722)	0.416
Nutritional risk by NRS2002	0.619 (0.271, 1.411)	0.254
GLIM-defined malnutrition	1.093 (0.494, 2.417)	0.827
Hemoglobin, g/L	0.965 (0.940, 0.991)	0.010	0.958 (0.917, 1.000)	0.051
Albumin, g/L	0.900 (0.818, 0.990)	0.030	0.951 (0.814, 1.111)	0.526
Duct-mucous anastomosis	0.417 (0.186, 0.935)	0.034	0.486 (0.153, 1.548)	0.222
Intraoperative hemorrhage, mL	1.001 (1.000, 1.002)	0.003	1.001 (1.000, 1.002)	0.048
Pancreatic duct diameter, cm	0.707 (0.343, 1.455)	0.346
Preoperative PMD, HU	1.004 (0.959, 1.051)	0.862
Preoperative TPA, cm^2	0.999 (0.998, 1.000)	0.024	0.999 (0.998, 1.000)	0.065
Preoperative TPAI, cm^2/m^2	0.621 (0.451, 0.854)	0.003	0.605 (0.414, 0.883)	0.009
TPAI-defined sarcopenia	8.424 (3.327, 21.333)	0.000	8.256 (2.890, 23.583)	0.000
Sarcopenic overweight/obesity	9.010 (3.014, 26.928)	0.000	7.462 (2.084, 26.724)	0.002

Abbreviations: NRS, nutritional risk screening; GLIM, global leadership initiative malnutrition; TPAI, total psoas area index; PMD, psoas muscle density; HU, Hounsfield units.