Table 1.

Demographic and clinical characteristics of study population by subgroups.

	n 428	Full PROTECT cohort	Gene expression array [GEA]
			n 313	Complete GEA cohort	n 284	Analysed GEA cohort	n 88	Mesalamine only	n 169	Moderate-to-severe disease	n 20	Controls
Demographic
Age, years	428	12.7 ± 3.3	313	12.9 ± 3.2	284	12.8 ± 3.1	88	12.9 ± 3.1	169	12.9 ± 3.1	20	13.8 ± 3.5
Sex	428		313		284		88				20
Female		212 [50]		147 [47]		132 [46]		43 [49]	169	76 [45]		11 [55]
Male		216 [50]		166 [53]		152 [54]		45 [51]		93 [55]		9 [45]
Race	420		307		278		86		165		20
White		351 [84]		259 [84]		237 [85]		69 [80]		144 [87]		17 [85]
Non-white		69 [16]		48 [16]		41 [15]		17 [20]		21 [13]		3 [15]
Ethnicity	424		310		283		87		169		20
Hispanic or Latino		38 [9]		27 [9]		24 [8]		11 [13]		10 [6]		0
Not Hispanic or Latino		386 [91]		283 [91]		259 [92]		76 [87]		159 [94]		20 [100]
BMI Z score	428	−0.2 ± 1.3	313	−0.2 ± 1.3	284	−0.2 ± 1.3	88	−0.1 ± 1.2	169	−0.3 ± 1.4	20	0.2 ± 1.6
Initial treatment	428		313		284		88		169
Mesalamine		136 [32]		101 [32]		88 [31]		88 [100]		0
Oral CS		144 [34]		106 [34]		97 [34]		0		70 [41]
IV CS		148 [35]		106 [34]		99 [35]		0		99 [59]
Clinical
Disease extent	428		313		284		88		169
Proctosigmoiditis		29 [7]		21 [7]		18 [6]		16 [18]		2 [1]
Left-sided colitis		44 [10]		35 [11]		30 [11]		20 [23]		5 [3]
Extensive/pancolitis		355 [83]		257 [82]		236 [83]		52 [59]		162 [96]
PUCAI score [0–89]	428	50 ± 20	313	50 ± 20	284	51 ± 20	88	31 ± 12	169	64 ± 13
<45		156 [36]		116 [37]		102 [36]		70 [80]		5 [3]
≥45		272 [64]		197 [63]		182 [64]		18 [20]		164 [97]
Mayo endoscopy sub-score [range 0–]	428	2.2 ± 0.7	313	2.2 ± 0.7	284	2.2 ± 0.7	88	1.8 ± 0.6	169	2.4 ± 0.6
1 = Mild		59 [14]		45 [14]		39 [14]		28 [32]		6 [3]
2 = Moderate		224 [52]		163 [52]		145 [51]		48 [54]		81 [48]
3 = Severe		145 [34]		105 [34]		100 [35]		12 [14]		82 [49]
Hgb, g/dL	402		294		268		80		162
Mean		11.4 ± 2.2		11.5 ± 2.2		11.5 ± 2.2		12.4 ± 1.8		11 ± 2.2
<10		98 [24]		64 [22]		62 [23]		6 [8]		52 [32]
CRP	315		237				59		140
>ULN		144 [46]		112 [47]		103 [47]		10 [17]		82 [59]
>2× ULN		97 [31]		79 [33]		73 [33]		6 [10]		60 [43]
ESR, mm/h	385		285		258		77		158
Median		25 [12-42]		24 [12-39]		24 [12-39]		14 [7-23]		30 [17-46]
Albumin, g/dL	422		311		282		87		168
Mean		3.7 ± 0.7		3.7 ± 0.7		3.7 ± 0.7		4.0 ± 0.7		3.5 ± 0.7
<3.5		138 [33]		100 [32]		92 [33]		13 [15]		69 [41]
Vit D, ng/mL	393		296		268		85		158
Median		29 [24-35]		28 [24-34]		28 [24-34]		28 [24-34]		28 [23-34]
<20		42 [11]		34 [11]		32 [12]		10 [12]		21 [13]
20–30		183 [46]		140 [47]		127 [47]		44 [52]		71 [45]
≥30		168 [43]		122 [41]		109 [41]		31 [36]		66 [42]
Baseline faecal calprotectin, –g/g	239		181		165		49		101
Median		2352 [1202–3928]		2634 [1212–4022]		2480 [1212–4022]		1629 [772–3632]		3333 [1421–4384]
>250		226 [95]		171 [94]		155 [94]		40 [82]		100 [99]
Rectal eosinophils, >32/hpf	367	210 [57]	300	161 [54]	272	144 [53]	84	45 [54]	162	80 [49]

Results are expressed as mean ± SD, n [%] or median [interquartile range]. Analysed GEA cohort excludes patients with protocol violations per PROTECT. IFX, infliximab; PUCAI, Pediatric Ulcerative Colitis Activity Index; BMI, body mass index; CS, corticosteroids; IV, intravenous; Hgb, haemoglobin; CRP, C-reactive protein; ULN, upper limit of normal; ESR, erythrocyte sedimentation rate; vit D, vitamin D; hpf, high-power field.