J Hematol

Journal of Hematology, ISSN 1927-1212 print, 1927-1220 online, Open Access

Article copyright, the authors; Journal compilation copyright, J Hematol and Elmer Press Inc

Journal website https://www.thejh.org

Original Article

Volume 11, Number 2, April 2022, pages 55-61

Iron Deficiency Anemia: An Overlooked Complication of Crohn’s Disease

Figure 1. Case selection flowchart. HCUP: Healthcare Cost and Utilization Project; NRD: Nationwide Readmissions Database; CD: Crohn’s disease.

**Table 1.** Baseline Characteristics of CD Patients With and Without IDA
	IDA absent (n = 62,586)	IDA present (n = 5,495)	P value
^aMann-Whitney test. ^bPearson Chi-square test. IDA: iron deficiency anemia; CD: Crohn’s disease; IQR: interquartile range.
Median age (IQR)	54 (37 - 68)	47 (32 - 65)	< 0.001^a
Sex (%)
Male	26,561 (42.4)	2,087 (38)	< 0.001^b
Female	36,025 (57.6)	3,408 (62)
Bed size of the hospital (%)
Small	10,698 (17.1)	913 (16.6)	0.211^b
Medium	17,124 (27.4)	1,462 (26.6)
Large	34,764 (55.5)	3,120 (56.8)
Insurance (%)
Medicare	25,509 (40.8)	1,966 (35.8)	< 0.001^b
Medicaid	8,690 (13.9)	986 (17.9)
Private insurance	24,034 (38.4)	2,156 (39.2)
Self-pay	2,326 (3.7)	218 (4)
No charge	1,693 (2.7)	139 (2.5)
Other	334 (0.5)	30 (0.5)
Median household income quartile for patient ZIP code (%)
0 - 25th percentile	14,252 (22.8)	1,331 (24.2)	0.011^b
26th -50th percentile	17,066 (27.3)	1,480 (26.9)
51st - 75th percentile	16,678 (26.6)	1,493 (27.2)
76th - 100th percentile	14,590 (23.3)	1,191 (21.7)
Hospital teaching status of urban hospitals (%)
Non-metropolitan hospital	4,113 (6.6)	272 (4.9)	< 0.001^b
Metropolitan non-teaching	13,137 (21)	1,027 (18.7)
Metropolitan teaching	45,336 (72.4)	4,196 (76.4)

Table 1. Baseline Characteristics of CD Patients With and Without IDA

IDA absent (n = 62,586)

IDA present (n = 5,495)

P value

^aMann-Whitney test. ^bPearson Chi-square test. IDA: iron deficiency anemia; CD: Crohn’s disease; IQR: interquartile range.

Median age (IQR)

54 (37 - 68)

47 (32 - 65)

< 0.001^a

Sex (%)

Male

26,561 (42.4)

2,087 (38)

< 0.001^b

Female

36,025 (57.6)

3,408 (62)

Bed size of the hospital (%)

Small

10,698 (17.1)

913 (16.6)

0.211^b

Medium

17,124 (27.4)

1,462 (26.6)

Large

34,764 (55.5)

3,120 (56.8)

Insurance (%)

Medicare

25,509 (40.8)

1,966 (35.8)

< 0.001^b

Medicaid

8,690 (13.9)

986 (17.9)

Private insurance

24,034 (38.4)

2,156 (39.2)

Self-pay

2,326 (3.7)

218 (4)

No charge

1,693 (2.7)

139 (2.5)

Other

334 (0.5)

30 (0.5)

Median household income quartile for patient ZIP code (%)

0 - 25th percentile

14,252 (22.8)

1,331 (24.2)

0.011^b

26th -50th percentile

17,066 (27.3)

1,480 (26.9)

51st - 75th percentile

16,678 (26.6)

1,493 (27.2)

76th - 100th percentile

14,590 (23.3)

1,191 (21.7)

Hospital teaching status of urban hospitals (%)

Non-metropolitan hospital

4,113 (6.6)

272 (4.9)

< 0.001^b

Metropolitan non-teaching

13,137 (21)

1,027 (18.7)

Metropolitan teaching

45,336 (72.4)

4,196 (76.4)

**Table 2.** Comorbid Diseases Among CD Patients With IDA
	IDA absent (n = 62,586)	IDA present (n = 5,495)	P value^a
^aPearson Chi-square test. IDA: iron deficiency anemia; CD: Crohn’s disease; COPD: chronic obstructive pulmonary disease; GI: gastrointestinal; CKD: chronic kidney disease.
Hypertension (%)	19,016 (30.4)	1,275 (23.2)	< 0.001
Diabetes mellitus (%)	9,775 (15.6)	751 (13.7)	< 0.001
Weight disorders (%)			< 0.001
Obesity	8,017 (12.8)	643 (11.7)
Weight loss	801 (1.3)	151 (2.7)
Hypothyroidism (%)	6,913 (11)	567 (10.3)	0.098
Crohn’s complication status (%)			< 0.001
Crohn’s without complications	48,488 (77.5)	3,616 (65.8)
Crohn’s with complications	13,637 (21,8)	1,832 (33.3)
Unspecified complications status	461 (0.7)	47 (0.9)
COPD (%)	7,160 (11.4)	451 (8.2)	< 0.001
Celiac disease (%)	314 (0.5)	38 (0.7)	0.060
Thrombocytopenia (%)	2,068 (3.3)	212 (3.9)	0.029
CKD (%)	5,808 (9.3)	578 (10.5)	0.003
Major depressive disorder (%)	11,580 (17.6)	1,186 (18.9)	0.007
Heart failure (%)	5,010 (8)	457 (8.3)	0.415
Cirrhosis (%)	1,121 (1.8)	129 (2.3)	0.003
Crohn’s disease with fistula (%)	2,081 (3.3)	303 (5.5)	< 0.001
Crohn’s disease with abscess (%)	1,926 (3.1)	343 (6.2)	< 0.001
Crohn’s disease with obstruction (%)	7,186 (11.5)	610 (11.1)	0.395
Lower GI bleeding (%)	4,518 (7.2)	991 (18)	< 0.001
Diverticulosis (%)	2,696 (4.3)	259 (4.7)	0.157

Table 2. Comorbid Diseases Among CD Patients With IDA

IDA absent (n = 62,586)

IDA present (n = 5,495)

P value^a

^aPearson Chi-square test. IDA: iron deficiency anemia; CD: Crohn’s disease; COPD: chronic obstructive pulmonary disease; GI: gastrointestinal; CKD: chronic kidney disease.

Hypertension (%)

19,016 (30.4)

1,275 (23.2)

< 0.001

Diabetes mellitus (%)

9,775 (15.6)

751 (13.7)

< 0.001

Weight disorders (%)

< 0.001

Obesity

8,017 (12.8)

643 (11.7)

Weight loss

801 (1.3)

151 (2.7)

Hypothyroidism (%)

6,913 (11)

567 (10.3)

0.098

Crohn’s complication status (%)

< 0.001

Crohn’s without complications

48,488 (77.5)

3,616 (65.8)

Crohn’s with complications

13,637 (21,8)

1,832 (33.3)

Unspecified complications status

461 (0.7)

47 (0.9)

COPD (%)

7,160 (11.4)

451 (8.2)

< 0.001

Celiac disease (%)

314 (0.5)

38 (0.7)

0.060

Thrombocytopenia (%)

2,068 (3.3)

212 (3.9)

0.029

CKD (%)

5,808 (9.3)

578 (10.5)

0.003

Major depressive disorder (%)

11,580 (17.6)

1,186 (18.9)

0.007

Heart failure (%)

5,010 (8)

457 (8.3)

0.415

Cirrhosis (%)

1,121 (1.8)

129 (2.3)

0.003

Crohn’s disease with fistula (%)

2,081 (3.3)

303 (5.5)

< 0.001

Crohn’s disease with abscess (%)

1,926 (3.1)

343 (6.2)

< 0.001

Crohn’s disease with obstruction (%)

7,186 (11.5)

610 (11.1)

0.395

Lower GI bleeding (%)

4,518 (7.2)

991 (18)

< 0.001

Diverticulosis (%)

2,696 (4.3)

259 (4.7)

0.157