Long-Term Weight Loss Outcome of Laparoscopic Sleeve Gastrectomy Predicted by the Percentage of Excess Weight Loss at 6 Months in Chinese Patients with Body Mass Index ≥ 32.5 Kg/m²

Figures & data

Table 1 The Preoperative Patients’ Characteristics

Variable	Value
Age (years)	31 (25, 37)^a
Gender
Female (%)	112 (36.48%)^b
Male (%)	195 (63.52%)
The ethnic
Han (%)	274 (89.25%)
Other ethnics (%)	33 (10.75%)
Residence
Urban (%)	237 (77.20%)
Rural (%)	70 (22.80%)
North & South
North (%)	29 (9.45%)
South (%)	278 (90.55%)
Preoperative BMI (kg/m^2)	39.68 (35.68, 45.47)
T2DM (%)	147 (47.88%)
Hypertension (%)	94 (30.62%)
Hyperlipidemia (%)	177 (57.65%)
Hyperuricemia (%)	242 (78.83%)
Fatty liver (%)	296 (96.42%)
OSA (%)	301 (98.05%)
PCOS (%)	79 (40.51%)

Notes: ^aMedian (upper and lower quartiles). ^bNo.(%).

Abbreviations: BMI, body mass index; T2DM, type 2 diabetes mellitus; OSA, obstructive sleep apnea; PCOS, polycystic ovary syndrome.

Table 2 Operation-Related Indicators

Variable	Value
Operation time (min)	80 (60, 100)^a
Intraoperative bleeding volume (mL)	20 (10, 50)
Hospital stay (day)	3 (2, 4)
Expense (¥)	68,725.28 ± 17,583.21^b
Time to first liquid intake (day)	2 (2, 2)

Notes: ^aMedian (upper and lower quartiles). ^bMean ± SD. ¥ is Chinese currency symbol.

Table 3 The Incidence of Postoperative Complications

Variable	Value
Mortality	0 (0.00)^a
Anastomotic fistula	0 (0.00)
Hemorrhage	0 (0.00)
Anastomotic stenosis	0 (0.00)
Nausea and vomiting	92 (29.97%)
Emaciation	2 (0.65%)
Hypoproteinemia	15 (4.89%)
Anemia	6 (1.95%)
Alopecia	107 (34.85%)
Functional dyspepsia	29 (9.45%)
Hypoglycemia	12 (3.91%)
Gallstones	29 (9.45%)
Hypotension	7 (2.23%)
Hypocalcemia	15 (4.89%)
Iron deficiency	13 (4.23%)
Hypomagnesemia	0 (0.00)
Folic acid deficiency	11 (3.58%)
VitB12 deficiency	5 (1.67%)
Other rare complications	10 (3.26%)

Note: ^aNo.(%).

Table 4 The Comparison of the Baseline Data Between Successful and Fail Weight Loss Groups at 5 Years (Reviewer #1, Comment #11)

	Successful Weight Loss Group (n=235)	Failed Weight Loss Group (n=72)	x^2/z	P value
Age (years)	31 (25, 38)^a	31 (26, 36)	−0.466	0.641
Gender
Male (%)	84 (35.74%)^b	28 (38.89%)	0.235	0.628
Female (%)	151 (64.26%)	44 (61.11%)
The ethnic
Han (%)	210 (89.36%)	64 (88.89%)	0.013	0.910
Other ethnics (%)	25 (10.64%)	8 (11.11%)
Residence
Urban (%)	185 (78.72%)	52 (72.22%)	1.323	0.250
Rural (%)	50 (21.28%)	20 (27.78%)
North & South
North (%)	25 (10.64%)	4 (5.56%)	1.665	0.197
South (%)	210 (89.36%)	68 (94.44%)
Preoperative BMI (kg/m^2)	38.51 (35.26, 44.10)	43.64 (38.69, 51.24)	−4.515	0.001
T2DM (%)	115 (48.94%)	32 (44.44%)	0.446	0.504
Hypertension (%)	71 (30.21%)	23 (31.94%)	0.078	0.780
Hyperlipidemia (%)	138 (58.72%)	39 (54.17%)	0.469	0.494
Hyperuricemia (%)	182 (77.45%)	60 (83.33%)	1.144	0.285
Fatty liver (%)	225 (95.74%)	71 (98.61%)	–	0.468
OSA (%)	229 (97.45%)	72 (100%)	–	0.342
PCOS (%)	52 (34.44%)	27 (61.36%)	10.25	0.001

Notes: ^aMedian (upper and lower quartiles). ^bNo.(%). x²/z is represented the result of the chi-square test, the larger the value, the smaller the p-value, the better the significance. Significant differences in preoperative BMI and PCOS between successful and fail weight loss groups.

Table 5 Logistic Regression Analysis of Factors for Successful Weight Loss (Reviewer #1, Comment # 15, 16)

	OR (95% CI)	P value
Preoperative BMI (kg/m^2)	0.982 (0.941, 1.024)^a	0.397
%EWL at 3 months	1.022 (0.985, 1.060)	0.243
%EWL at 6 months	1.051 (1.022, 1.081)	0.001

Notes: ^aMedian (upper and lower quartiles). %EWL at 6 months used to predict the long-term weight loss was significantly different from preoperative BMI and %EWL at 3 months.

Figure 1 The trends in the BMI (A) and %EWL (B) over time.

Note: Each point in the figure represents a patient, and the red horizontal line represents the median.

Figure 2 The histograms (A) and probability–probability plots (B) of standardized residuals for %EWL at 5 years.

Figure 3 ROC curve of %EWL at 6 months among patients with successful %EWL at 5 years after LSG.

Figure 4 Change in the mean %EWL among patients who achieved 58.57% EWL at 6 months compared to patients who did not.

Table 6 Cure Rates of Major Comorbidities in Patients with %EWL ≥ 58.57% and < 58.57% at 6 Months

	T2DM (n=147)		Hypertension (n=94)		Hyperlipidemia (n=177)
	Cured	Not Cured	Cured	Not Cured	Cured	Not Cured
%EWL < 58.57% at 6 months	38 (90.48%)^a	4 (9.52%)	35 (83.33%)	7 (16.67%)	35 (53.03%)	31 (46.97%)
%EWL ≥58.57% at 6 months	56 (90.32%)	6 (9.68%)	47 (90.38%)	5 (11.90%)	86 (77.48%)	25 (22.52%)
P	1.000		0.308		0.001

Notes: ^aNo.(%). There was a significant difference in cure rates for hyperlipidemia in patients with %EWL ≥ 58.57% and < 58.57% at 6 months.

Figure 5 Calibration curve for %EWL at 6 months to predict weight loss at 5 years.