Hypothesized summative anal physiology score correlates but poorly predicts incontinence severity

Table 1 Hypothesized anal physiology score

	Maximum resting pressure (mmHg)	Anal canal length (cm)	Internal sphincter defect	External sphincter defect	PNTML
0	> 40	> 3	Intact	Intact	Normal
1	> 30, ≤ 40	> 2, ≤ 3	≤ ¼ defect	≤ ¼ defect	-
2	> 20, ≤ 30	> 1, ≤ 2	> ¼, ≤ ½	> ¼, ≤ ½	Unilateral neuropathy
3	> 10, ≤ 20	> ½, ≤ 1	> ½, ≤ ¾	> ½, ≤ ¾	-
4	≤ 10	≤ ½	> ¾	> ¾	Bilateral neuropathy

PNTML: Pudendal terminal motor latency.

Table 2 Cleveland Clinic Continence Score[4]

	Never	Rarely < 1/mo	Sometimes ≥ 1/mo	Usually ≥ 1/wk	Always ≥ 1/d
Gas	0	1	2	3	4
Liquid	0	1	2	3	4
Solids	0	1	2	3	4
Pads	0	1	2	3	4
Lifestyle	0	1	2	3	4

Table 3 Patient demographics for 508 patients presenting with faecal incontinence n (%)

	Men	Women
n	89 (17.5)	419 (82.5)
mean Age	57.8 (SD 15.1)	60.3 (SD 14.1)
Diabetes
Yes	10 (11.2)	17 (4.1)
No	72 (80.9)	362 (86.4)
Irritable bowel syndrome
Yes	9 (10.1)	16 (3.8)
No	73 (82.0)	363 (86.6)
Urinary incontinence
Yes	9 (10.1)	42 (10.0)
No	73 (82.0)	365 (87.0)
Previous pelvic surgery
Yes	13 (14.6)	197 (47.0)
No	70 (78.7)	184 (43.9)
Hysterectomy	-	148 (35.3)
Anterior resection	8 (9.0)	11 (2.6)
Rectopexy	3 (3.4)	15 (3.6)
Zaccharin's procedure	-	45 (10.7)
Bladder procedure	-	45 (10.7)
Previous OSR	-	12 (2.9)
Other gynae surgery	-	48 (11.5)
Prostatectomy	6 (6.7)	-
Anorectal surgery
Yes	37 (41.6)	85 (20.3)
No	45 (50.6)	373 (89.0)
Hemorrhoidectomy	17 (19.1)	34 (8.1)
Sphincterotomy	4 (4.5)	9 (2.1)
Anal dilatation	0 (0)	6 (1.4)
Fistulotomy	8 (9.0)	13 (3.1)

Total percentages may not add up to 100% because of missing data, other categories which have not been included in this table for simplicity or because patients might have had more than one procedure.

Table 4 Distribution of anal physiology score variables by gender

	Men	Women	P value	Mean reference range
Maximum RP (mmHg)				Men: 50-80
Mean	51.0 (SD 23.2)	38.8 (SD 15.6)	< 0.0001	Women: 30-60
Median	52.0 (IQR 33.5)	38.0 (IQR 22.5)
ACL (cm)				Men: 2.5-3.5
Mean	1.7 (SD 1.4)	0.7 (SD 0.8)	< 0.0001	Women: 2.0-3.0
Median	2.0 (IQR 2.8)	0.5 (IQR 1.0)
IAS defect
Intact	61 (68.5)	286 (68.3)	0.7	-
≤ ¼ defect	0 (0.0)	4 (1)	(c2 = 2.4, df = 4 )
> ¼, ≤ ½	12 (13.5)	49 (11.7)
> ½, ≤ ¾	2 (2.2)	21 (5.0)
> ¾	14 (15.7)	59 (14.1)
EAS defect
Intact	85 (95.5)	305 (73.0)	< 0.0001	-
≤ ¼ defect	0 (0.0)	2 (0.5)	(c2 = 21.7, df = 4)
> ¼, ≤ ½	2 (2.2)	62 (14.8)
> ½, ≤ ¾	1 (1.1)	36 (8.6)
> ¾	1 (1.1)	13 (3.1)
Pudendal Neuropathy
Normal	70 (78.7)	191 (45.6)	< 0.0001
Unilateral	3 (3.4)	67 (16.0)	(c2 = 43.1, df=2)	2.20 ms
Bilateral	6 (6.7)	137 (32.7)
Mean CCCS	5.9	8	0.001	-

CCCS: Cleveland Clinic Continence Scores; ACL: Anal canal length.

Table 5 Univariate associations between individual anal physiology score variables and Cleveland Clinic continence scores

	F value	df	P1 value	Proportion variability in CCCS explained
Maximum RP (mmHg)	13.8	1, 395	0.0002	3.10%
ACL	12.1	1, 395	0.0006	2.70%
IAS defect	2.2	4, 392	0.07	1.20%
EAS defect	2.3	4, 392	0.06	1.30%
Pudendal neuropathy	11.7	2, 394	< 0.0001	5.10%

¹Based on ANOVA procedure. CCCS: Cleveland Clinic Continence Scores; ACL: Anal canal length.

Table 6 Multiple regression analyses

Variable	Classification	Change in CCCS	P value
EAS defect	Intact	-	0.01
	¼	4
	½	0.3
	¾	1.5
	> ¾	5.1
PNTML	Normal	-	< 0.0001
	Unilateral neuropathy	1.2
	Bilateral neuropathy	2.6
Previous pelvic surgery	Yes	-	0.0007
	No	-1.6

CCCS: Cleveland Clinic Continence Scores; PNTML: Pudendal terminal motor latency.