Risk of anemia in morbidly obese patients after bariatric surgery in Taiwan

Table 1 Demographic characteristics of patients diagnosed morbid obesity receiving and not-receiving bariatric surgery

Variable	Receiving bariatric surgery				P value1
	No [n = 1509 (34.51%)]		Yes [n = 2864 (65.49%)]
	n	%	n	%
Malabsorptive procedures	-	-	1773	61.91	-
Restrictive procedures	-	-	2465	86.07	-
Sex					< 0.0001
Female	818	54.21	1855	64.77
Male	691	45.79	1009	35.23
Age at baseline, yr					< 0.0001
20-29	302	20.01	1305	45.57
30-64	1034	68.52	1558	54.4
65-100	173	11.46	1	0.03
mean ± SD	44.30 ± 15.25		33.09 ± 9.07		< 0.00012
Comorbidities
Hypertension	751	49.77	254	8.87	< 0.0001
Hyperlipidemia	314	20.81	110	3.84	< 0.0001
Diabetes mellitus	525	34.79	174	6.08	< 0.0001
Coronary artery disease	261	17.3	69	2.41	< 0.0001
Congestive heart failure	243	16.1	39	1.36	< 0.0001
Stroke	123	8.15	37	1.29	< 0.0001
Chronic kidney disease	124	8.22	22	0.77	< 0.0001
Asthma	186	12.33	75	2.62	< 0.0001
Chronic obstructive pulmonary disease	145	9.61	34	1.19	< 0.0001
Peripheral arterial occlusive disease	29	1.92	3	0.1	< 0.0001a
Gastrointestinal ulcer	185	12.26	73	2.55	< 0.0001
Gastrointestinal bleeding	44	2.92	12	0.42	< 0.0001

¹Chi-square test.

²t test.

^aFisher’s exact test. The means (median) of follow-up period were 5.68 (5.31) years and 4.21 (3.84) years for the study bariatric surgery cohort and comparison cohorts, respectively. SD: Standard deviation.