Prevalence and factors associated with vitamin C deficiency in inflammatory bowel disease

Table 2 Prevalence of vitamin C deficiency in covariate populations

Covariates	Prevalence of vitamin C deficiency in patients with covariate	Prevalence of vitamin C deficiency in patients without covariate	P value
IBD type
CD	49/201 (24.4%)	-	0.1
UC	16/100 (16.0%)	-	0.1
Small bowel disease	38/165 (23.0%)	11/36 (30.6%)	0.3
Penetrating disease	17/47 (36.2%)	32/154 (20.8%)	0.031
IBD related surgery	28/109 (25.7%)	37/192 (19.3%)	0.2
CD	25/96 (26.0%)	24/105 (22.9%)	0.6
UC	3/13 (23.1%)	13/87 (14.9%)	0.4
Obesity (BMI ≥ 30)	15/42 (35.7%)	49/249 (19.7%)	0.021
Active smoking	3/6 (50.0%)	62/295 (21.0%)	0.1
Current biologic use	38/133 (28.6%)	26/167 (15.6%)	0.0061
CRP > 0.9 mg/dL	25/64 (39.1%)	36/213 (16.9%)	< 0.0011
CD	21/51 (41.2%)	24/134 (17.9%)	0.0011
UC	4/13 (30.8%)	12/79 (15.2%)	0.2
Fecal calprotectin > 250 ug/g	10/20 (50.0%)	12/60 (20.0%)	0.0091
CD	9/16 (56.3%)	10/38 (26.3%)	0.041
UC	1/4 (25.0%)	2/22 (9.1%)	0.4
Iron deficiency	17/59 (28.8%)	39/193 (20.2%)	0.2
Vitamin D deficiency/insufficiency	11/38 (28.9%)	47/221 (21.3%)	0.3
Clinically active disease	35/134 (26.1%)	29/158 (18.4%)	0.1
CD	29/96 (30.2%)	20/99 (20.2%)	0.1
UC	6/38 (15.8%)	9/59 (15.3%)	0.9
Endoscopically severe disease	7/20 (35.0%)	21/93 (22.6%)	0.2
CD	5/12 (41.7%)	18/65 (27.7%)	0.3
UC	2/8 (25.0%)	3/28 (10.7%)	0.3

¹Patients with penetrating disease, obesity, biologic use, elevated C-reactive protein and elevated fecal calprotectin had increased frequency of vitamin C deficiency.

Clinically active disease was defined as Harvey-Bradshaw index > 5 for Crohn’s disease (CD), and stool frequency or rectal bleeding > 1 on modified partial Mayo score for ulcerative colitis (UC). Endoscopically severe disease was defined as simple endoscopic score CD > 15 in CD and endoscopic Mayo score ≥ 2 in UC. IBD: Inflammatory bowel disease; CD: Crohn’s disease; UC: Ulcerative colitis; BMI: Body mass index; CRP: C-reactive protein.