TABLE 1. Pre and postoperative clinical and laboratory parameters according to the type of operation performed.

Parameter	Technique	Pre-op	Post-op	p
BMI (kg/m²)	Bypass	44.3±4.2	27.9±4.1	<0.001
	Sleeve	42.1±4.1	28.6±5.8	<0.001
	p	0.239	0.730
Platelets (x1000)	Bypass	270±59	239±66	0.170
	Sleeve	283±45	279±71	0.832
	p	0.606	0.191
ALP (U/L)	Bypass	92.2±30.7	72.8±16.8	0.010
	Sleeve	105.5±20.6	103.0±70.3	0.910
	p	0.283	0.268
Ferritin (ng/ml)	Bypass	227.1±150.3	121.1±86.4	0.011
	Sleeve	232.6±76.1	133.6±103.1	0.069
	p	0.854	0.976
GGT (U/L)	Bypass	55.9±31.1	19.1±10.8	0.000
	Sleeve	111.0±151.8	64.5±116.3	0.123
	p	0.312	0.197
Glycemia (mg/dl)	Bypass	99.4±17.2	82.1±9.8	0.001
	Sleeve	102.75±10.2	90.2±8.6	0.007
	p	0.616	0.059
AST (U/L)	Bypass	30.8±16.2	25.5±6.9	0.338
	Sleeve	33.5±12.2	39.0±27.9	1.000
	p	0.408	0.358
ALT (U/L)	Bypass	42.1±20.6	28.3±10.6	0.023
	Sleeve	39.9±12.5	31.6±13.2	0.207
	p-	0,806	0,602

BMI=body mass index; ALP=alkaline phosphatase; GGT=gamma glutamyl transpeptidase; AST=aspartate aminotransferase; ALT=alanine aminotransferase.