Serum anti-enteric neuronal antibodies in patients with achalasia and their association with clinical profiles

Table 1 Correlation of achalasia of cardia clinical profiles and anti-enteric neuronal antibodies status, mean ± SD/n (%)/median interquartile range

Parameter	AENA negative (n = 38)	AENA positive (n = 59)	P value
Demography
Female	17 (44.7)	32 (54.2)	0.480
Age, year	41.6 ± 13.9	46.7 ± 14.2	0.082
Weight, kg	57.0 (50.0 to 65.0)	58.00 (53.0 to 66.0)	0.453
BMI, kg/m2	20.3 (18.3 to 21.4)	21.63 (19.2 to 24.2)	0.051
Disease duration, year	3.6 (2.0 to 9.0)	4.0 (2.5 to 5.0)	0.792
Previous intervention	4 (10.5)	11 (18.6)	0.559
Eckardt scores	7.0 (5.0 to 8.0)	6.0 (5.0 to 8.0)	0.905
CARS scores	4.0 (3.0 to 5.0)	5.0 (3.0 to 5.0)	0.045a
HRM parameters
IRP, mmHg	20.2 ± 10.5	17.2 ± 9.0	0.214
BLESP, mmHg	29.8 (22.1 to 40.0)	30.1 (22.4 to 37.5)	0.714
DCI, mmHg/second/cm	47.0 (2.0 to 160.0)	59.5 (2.0 to 176.0)	0.888
AC subtype			> 0.99
Type I	19 (50.0)	28 (47.5)
Type II	18 (47.4)	29 (49.2)
Barium esophagogram
Barium width, mm	41.5 (36.5 to 49.0)	41.5 (35.0 to 47.0)	0.652
Esophageal distortion			0.503
None	18 (56.3)	23 (42.6)
Mild	6 (18.8)	21 (38.9)
Moderate	6 (18.8)	6 (11.1)
Severe	2 (6.3)	4 (7.4)

^aP < 0.05.

Comparisons were performed using Student’s t-test, Mann-Whitney U test, or χ² test, as appropriate. AENA: Anti-enteric neuronal antibodies; BMI: Body mass index; CARS: Contents, anatomy, resistance, and stasis; HRM: High-resolution manometry; IRP: Integrated relaxation pressure; BLESP: Basal lower esophageal sphincter pressure; AC: Achalasia of cardia; DCI: Distal contractile integral.

Table 2 Comparison of individual contents, anatomy, resistance, and stasis components across different intensities of anti-enteric neuronal antibodies, n (%)

CARS component1	AENA negative (n = 38)	AENA positive (n = 58)	P value	AENA moderate-positive (n = 36)	AENA strong-positive (n = 22)	P value
Content			0.750			0.233
None	1 (2.6)	5 (8.6)		5 (13.9)	0 (0.0)
Retained secretions or liquid	22 (57.9)	30 (51.7)		18 (50.0)	12 (54.5)
Retained solids	15 (39.5)	23 (39.7)		13 (36.1)	10 (45.5)
Anatomy			< 0.001b			< 0.001b
Normal caliber	3 (7.9)	4 (6.9)		4 (11.1)	0 (0.0)
Dilated lumen	32 (84.2)	30 (51.7)		23 (63.9)	7 (31.8)
Severely dilated lumen	3 (7.9)	24 (41.4)		9 (25.0)	15 (68.2)
Resistance			0.431			0.017a
None	5 (13.2)	3 (5.2)		2 (5.6)	1 (4.5)
Mild	20 (52.6)	33 (56.9)		25 (69.4)	8 (36.4)
Significant	13 (34.2)	22 (37.9)		9 (25.0)	13 (59.1)
Stasis			0.626			0.059
No evidence for stasis	27 (71.1)	39 (67.2)		21 (58.3)	18 (81.8)
Chronic stasis changes	11 (28.9)	17 (29.3)		13 (36.1)	4 (18.2)
Candida esophagitis	0 (0.0)	2 (3.4)		2 (5.6)	0 (0.0)

^aP < 0.05.

^bP < 0.01.

¹The sample size for anti-enteric neuronal antibodies (AENA)-positive in assessing CARS (contents, anatomy, resistance, and stasis) was 58 (not 59), due to one patient in the moderate-positive AENA group refusing endoscopic assessment.

Comparisons were performed using the Mann-Whitney U test. CARS: Contents, anatomy, resistance, and stasis; AENA: Anti-enteric neuronal antibodies.

Table 3 Association between clinical characteristics of achalasia and anti-enteric neuronal antibodies intensity, mean ± SD/n (%)/median interquartile range

Parameter	AENA moderate-positive (n = 37)	AENA strong-positive (n = 22)	P value
Demographic
Female	21 (56.8)	11 (50.0)	0.815
Age, year	46.6 ± 14.8	46.8 ± 13.5	0.959
Weight, kg	60.0 ± 9.9	59.1 ± 11.6	0.770
BMI, kg/m2	21.9 ± 3.0	21.0 ± 3.3	0.285
Disease duration, year	3.5 (2.0 to 5.0)	4.7 (3.0 to 6.0)	0.100
Previous intervention	7 (18.9)	2 (9.1)	0.461
Eckardt scores	6.8 ± 1.9	6.4 ± 1.6	0.395
CARS scores	4.0 (3.0 to 5.0)	5.0 (4.0 to 5.0)	0.034a
HRM parameters
IRP, mmHg	14.5 (10.2 to 19.8)	22.1 (13.5 to 29.3)	0.018a
BLESP, mmHg	29.3 (23.2 to 33.6)	32.2 (21.7 to 45.8)	0.154
DCI, mmHg/second/cm	56.0 (2.0 to 108.0)	125.0 (0.0 to 361.0)	0.223
AC subtype			0.654
Type I	19 (52.8)	9 (42.9)
Type II	17 (47.2)	12 (57.1)
Barium esophagogram
Barium width, mm	38.3 (35.0 to 45.0)	45.0 (40.0 to 51.0)	0.029a
Esophageal distortion			0.503
None	13 (39.4)	10 (47.6)
Mild	14 (42.4)	7 (33.3)
Moderate	5 (15.2)	1 (4.8)
Severe	1 (3.0)	3 (14.3)

^aP < 0.05.

Comparisons were performed using Student’s t-test, Mann-Whitney U test, or χ² test, as appropriate. AENA: Anti-enteric neuronal antibodies; BMI: Body mass index; CARS: Contents, anatomy, resistance, and stasis; HRM: High-resolution manometry; IRP: Integrated relaxation pressure; BLESP: Basal lower esophageal sphincter pressure; AC: Achalasia of cardia; DCI: Distal contractile integral.

Table 4 Comparison of treatment outcomes between anti-enteric neuronal antibodies-positive and -negative patients with achalasia after overlap weighting, mean ± SD/median interquartile range

Outcomes	AENA negative (n = 18)	AENA positive (n = 23)	P value
1-month follow-up
Eckardt scores	0.00 (0.00 to 1.00)	1.00 (0.58 to 2.00)	0.031a
Δ Eckardt scores1	6.00 (5.00 to 7.31)	4.68 (4.00 to 6.48)	0.173
6-month follow-up
Eckardt scores	0.00 (0.00 to 1.00)	1.00 (1.00 to 2.00)	0.005b
Δ Eckardt scores1	5.51 (4.00 to 9.00)	5.00 (4.00 to 6.20)	0.233
CARS scores	1.00 (1.00 to 1.43)	1.00 (1.00 to 2.05)	0.915
Δ CARS scores1	2.89 (1.00 to 4.00)	2.98 (1.00 to 4.00)	0.939
Reflux esophagitis			0.497
None	68.9	64.1
Los Angeles-A	10.0	28.1
Los Angeles-B	10.9	2.8
Los Angeles-C	10.1	5.0
IRP, mmHg	1.99 (0.69 to 4.38)	2.36 (0.67 to 5.00)	0.840
Δ IRP, mmHg1	9.67 (-2.05 to 13.77)	13.40 (7.55 to 17.69)	0.359
Barium width, mm	25.10 (11.00 to 30.00)	22.84 (15.39 to 36.55)	0.674
Δ Barium width, mm1	16.82 (9.18 to 24.17)	19.29 (0.16 to 26.08)	0.574

^aP < 0.05.

^bP < 0.01.

¹Changes compared to these at baseline.

Statistical comparisons were performed using weighted Wilcoxon rank-sum tests for continuous variables and weighted χ² tests for categorical variables to account for overlap weights. AENA: Anti-enteric neuronal antibodies; CARS: Contents, anatomy, resistance, and stasis; IRP: Integrated relaxation pressure.

Table 5 Multivariable linear regression model for contents, anatomy, resistance, and stasis scores

Variable	β (95%CI)	P value
AENA intensity (negative)
Moderate-positive	0.08 (-0.65 to 0.80)	0.838
Strong-positive	0.95 (0.37-1.53)	0.002b
Age (per year)	0.00 (-0.02 to 0.02)	0.851
Gender (male)	0.15 (-0.41 to 0.71)	0.596
Disease duration (per year)	0.00 (-0.04 to 0.04)	0.943
AC subtype	-0.06 (-0.64 to 0.52)	0.841

^bP < 0.01.

The model was adjusted for age, sex, disease duration, and achalasia subtype. AENA: Anti-enteric neuronal antibody; CI: Confidence interval; AC: Achalasia of cardia.

Table 6 Dose-response association between anti‐enteric neuronal antibody intensity levels and contents, anatomy, resistance, and stasis scores

Variable	β (95%CI)	P value
AENA intensity (per category increase)	0.43 (0.14-0.73)	0.005b
Age (per year)	-0.00 (-0.02 to 0.02)	0.990
Gender (male vs female)	0.12 (-0.44 to 0.68)	0.670
Disease duration (per year)	0.00 (-0.03 to 0.04)	0.802
Achalasia subtype	-0.04 (-0.62 to 0.54)	0.893

^bP < 0.01.

The model was adjusted for age, sex, disease duration, and achalasia subtype. Anti-enteric neuronal antibody intensity was analyzed as an ordinal variable (negative = 0; moderate-positive = 1; strong-positive = 2). AENA: Anti-enteric neuronal antibody; CI: Confidence interval.