Multicenter, randomized study to optimize bowel preparation for colon capsule endoscopy

Table 1 Bowel preparation regimens

Time	Study regimen	Control regimen
2 d prior	≥ 2400 mL (10 glasses) of liquid during the day; 4 senna tablets at bedtime
1 d prior	Clear liquid diet all day; 2 L sulfate-free PEG-ELS1 at about 7-9 pm (one 237 mL-296 mL cup (8-10 oz. cup) every 10-15 min)
Day of capsule procedure
45-75 min prior to capsule ingestion	2 L sulfate-free PEG-ELS
1 h after capsule ingestion	Optional prokinetics (only if capsule in stomach > 1 h): 10 mg metoclopramide or 250 mg erythromycin
1st boost: After capsule entry into small bowel2	89 mL (3 oz) OSS plus 60 mL diatrizoate solution1	89 mL (3 oz.) OSS
2nd boost: 3 h after 1st boost, only if capsule not excreted	89 mL (3 oz) OSS plus 30 mL diatrizoate solution1	89 mL (3 oz.) OSS
3rd boost: 2 h after 2nd boost, only if capsule not excreted	10 mg bisacodyl suppository
2 h after 3rd boost, or after capsule passes (whichever occurs first)	Standard full meal

¹Diatrizoate solution = diatrizoate meglumine and diatrizoate sodium solution;

²Clear liquids permitted after ingestion of 1^st boost, PEG-ELS: Polyethylene glycol-electrolyte solution; OSS: Oral sulfate solution.

Table 2 Subject characteristics

	Study regimen, n = 62	Control regimen, n = 59	P value
Age (yr)	55.20	55.10	0.888
Gender (male:female)	45:55	49:51	0.660
BMI (mean)	28.50	28.50	0.978

Table 3 Overall colon cleansing assessment

Overall cleansing assessment [95%CI]	Study regimen, n = 55	Control regimen, n = 52	P value
Adequate1	75.9 [62.4; 86.5]	77.3 [62.2; 88.5]	0.876
Excellent	16.7 [7.9; 29.3]	6.8 [1.4; 18.7]	0.216
Good	59.3 [45.0; 72.4]	70.5 [54.8; 83.2]	0.243
Fair	24.1 [13.5; 37.6]	22.7 [11.5; 37.8]	0.875
Poor	0.0 [0.0; 5.9]	0.0 [0.0; 6.6]	--

¹Includes both excellent and good cleansing.

Table 4 Polyp detection by size for the whole colon

Polyp size [95%CI]	Study regimen, n = 55	Control regimen, n = 52	P value
≥ 6 mm	36.4 [23.8; 50.4]	21.3 [10.7; 35.7]	0.096
≥ 10 mm	14.6 [6.5; 26.7]	8.5 [2.4; 20.4]	0.346
Any polyp	58.2 [44.1; 71.3]	46.8 [32.1; 61.9]	0.251

Table 5 Colon capsule endoscopy completion and transit times

	Study regimen, n = 55	Control regimen, n = 52	P value
CCE completion [95%CI]	90.9 [80.0; 97.0]	76.9 [63.2; 87.5]	0.0482
CCE excretion ≤ 12 h [95%CI]	90.9 [80.0; 97.0]	80.4 [66.9; 90.2]	0.121
GI tract transit - Ingestion to excretion1, mean (SD) [95%CI]	5:54 (6:00) [4:18; 7:30]	9:00 (11:48) [5:36; 12:24]	0.107
Colonic transit time1, mean (SD) [95%CI]	2:12 (1:36) [1:48; 2:42]	2:36 (1:30) [2:06; 3:06]	0.262
Colonic Transit < 40 min [95%CI]	21.8 [11.8; 35.0]	4.0 [0.5; 13.7]	0.0072

¹All transit times measured as (h:min);

²Statistically significant. CCE: Colon capsule endoscopy.

Table 6 Adverse events: Frequency and severity by subject

Adverse event	Study regimen, n = 62	Control regimen, n = 59	P value
Subjects with ≥ 1, n (%) [95%CI]	12 (19.4) [10.4; 31.4]	2 (3.4) [0.4; 11.7]	0.0062
Occurring in > 2% of subjects, n (%) [95%CI]
Headache	2 (3.2) [0.4; 11.2]	1 (1.7) [0.0; 9.1]
Nausea	4 (6.5) [1.8; 15.7]	2 (3.4) [0.4; 11.7]
Vomiting	2 (3.2) [0.2; 38.5]	0 (0) [0.0; 77.6]
Maximum AE severity1, n (%) [95%CI]
Mild	6 (50) [21.1; 78.9]	2 (100) [22.4; 100.0]
Moderate	5 (41.7) [15.2; 72.3]	0 (0) [0.0; 77.6]	0.308
Severe	1 (8.3) [0.2; 38.5]	0 (0) [0.0; 77.6]

¹Subjects were counted once according to maximum severity; 2_nd Statistically significant.

Table 7 Comparisons between Study regimen and Spada et al[15]: Bowel cleansing, capsule transit, and polyp detection

Parameter	Study regimen	Spada et al (4)1	P value
Adequate preparation-whole colon (% [95%CI])	75.9 [62.4; 86.5]	78.0[64.0; 88.5]	0.820
CCE completion (% [95%CI])	90.2 [79.8; 96.3]	96.0 [86.3; 99.5]	0.291
GI transit time2, mean (SD) [95%CI]	6:00 (6:12) [4:24; 7:36]	6:06 (4:48) [4:46; 7:26]	0.925
Polyp detection (% [95%CI])
≥ 6 mm	36.0 [22.9; 50.8]	25.0 [13.6; 39.6]	0.233
≥ 10 mm	16.0 [7.2; 29.1]	12.5 [4.7; 25.2]	0.619

¹1^st boost = 40 mL sodium phosphate liquid (NaP) and 50 mL diatrizoate solution;

²boost = 25 mL NaP and 25 mL diatrizoate solution; ²All transit times measured as (hour: minutes). CCE: Colon capsule endoscopy.

Table 8 Comparisons between Control regimen and Rex et al[1]: Bowel cleansing, capsule completion and transit, and polyp detection

Parameter	Control regimen	Rex et al (7)1	P value
Adequate preparation–whole colon (% [95%CI])	77.3 [62.2; 88.5]	71.4 [68.1; 74.5]	0.369
CCE completion (% [95%CI])	77.6 [64.7; 87.5]	89.0 [86.8; 91.0]	0.0413
GI transit time2, mean (SD) [95%CI]	2:48(1:36) [2:18; 3:18]	1:52 (1:40) [1:45; 1:59]	< 0.0013
Polyp detection (% [95%CI])
≥ 6 mm	21.3 [10.7; 35.7]	31.5 [28.1; 35.1]	0.100
≥ 10 mm	8.5 [2.4; 20.4]	11.4 [9.1; 14.0]	0.810

¹Used 6 ounces sulfate solution for 1^st and 2_nd boosts;

²All transit times measured as (hour: minutes);

³Statistically significant. CCE: Colon capsule endoscopy.