Effect of sex on the outcomes of peroral endoscopic myotomy for the treatment of achalasia

Table 1 Baseline characteristics of the cases, mean ± SD/n (%)

Characteristics	Total (n = 526)	Male (n = 238)	Female (n = 288)	P value
Age, year	45.01 ± 13.78	43.23 ± 13.54	46.48 ± 13.82	0.007
BMI, Kg/m2	21.49 ± 3.23	22.27 ± 3.29	20.85 ± 3.04	< 0.001
Course of disease, month (median IQR)	48 (24, 120)	48 (22.5, 120)	48 (24, 96)	0.584
ASA classification	Total (n = 496)	Male (n = 221)	Female (n = 275)	0.506
1	55 (11.1)	23 (10.4)	32 (11.6)
2	428 (86.3)	191 (86.4)	237 (86.2)
3	13 (2.6)	7 (3.2)	6 (2.2)
Chicago classification	Total (n = 437)	Male (n = 199)	Female (n = 238)	0.219
1	65 (14.9)	36 (18.1)	29 (12.2)
2	343 (78.5)	149 (74.9)	194 (81.5)
3	29 (6.6)	14 (7.0)	15 (6.3)
Follow-up period, month (median IQR)	41.0 (21.3, 64.6)	37.7 (19.9, 66.6)	43.0 (22.5, 64.3)	0.226
Previous treatment				0.584
Pneumatic dilation	58 (11.03)	29 (12.18)	29 (10.07)
Botox injection	27 (5.13)	10 (4.20)	17 (5.90)
laparoscopic heller myotomy	11 (2.09)	6 (2.52)	5 (1.74)
Tunnel length, cm (median IQR)	12 (10, 12)	12 (9.75, 12)	12 (10, 12)	0.074
Myotomy length, cm (median IQR)	7 (5.6, 9)	7 (6, 9)	7 (6, 9)	0.492
Myotomy length of esophagus, cm (median IQR)	5 (4.7)	5 (4, 7)	5 (4, 7)	0.369
Myotomy length of stomach, cm (median IQR)	2 (2, 2)	2 (2, 2)	2 (2, 2)	0.948

BMI: Body mass index; ASA: American Society of Anesthesiologists; IQR: Interquartile range.

Table 2 Comparison of pre-peroral endoscopic myotomy and post-peroral endoscopic myotomy clinical characteristics between male and female subgroups

Variables	Pre-POEM			Post-POEM
	Male (n = 238)	Female (n = 288)	P value	Male (n = 238)	Female (n = 288)	P value
Eckardt scores
Dysphagia			0.237			0.407
0	0	5		111	138
1	28	30		109	136
2	43	50		8	9
3	167	203		10	5
Regurgitation			0.734			0.858
0	34	44		158	196
1	53	62		69	82
2	77	82		9	9
3	74	100		2	1
Chest pain			0.008 (female > male)			0.052
0	132	120		181	197
1	74	112		54	90
2	24	34		2	1
3	8	22		1	0
Weight loss			0.850			1.000
0	49	62		230	277
1	35	47		7	9
2	67	84		1	1
3	87	95		0	1
Total Eckardt scores (median IQR)	7 (5, 9)	7 (5, 9)	0.393	1 (0, 2)	1 (0, 2)	0.761
HRM
LESP, mmHg (median IQR)	27.6 (20.5, 36.5)	32.8 (23.6, 42.2)	< 0.001 (female > male)	14.0 (10.1, 18.4)	14.8 (10.3, 21.4)	0.296
IRP, mmHg (median IQR)	22.3 (16.7, 29.7)	25.5 (19.6, 33.1)	0.001 (female > male)	8.2 (5.4, 14.1)	11.1 (7.8, 15.4)	0.084
Length of LES, cm (median IQR)	2.5 (2.0, 3.0)	2.6 (2.0, 3.1)	0.631	2.0 (1.7, 2.3)	1.8 (1.5, 2.7)	0.648
Iodipin column, mm (median IQR)
Height	86.0 (58.4, 126.5)	97.5 (67.1, 148.6)	0.127	50.5 (33.1, 77.3)	57.3 (33.1, 94.6)	0.601
Diameter	48.5 (35.5, 65.2)	41.9 (30.9, 53.1)	0.012 (female > male)	27.5 (16.1, 29.3)	24.6 (17.4, 34.0)	0.627

IQR: Interquartile range; POEM: Peroral endoscopic myotomy; HRM: High-resolution manometry; LESP: Lower esophageal sphincter pressure; IRP: Integrated relaxation pressure; LES: Lower esophageal sphincter.

Table 3 Comparison of clinical characteristics between male and female subgroups (year < 40)

Variables	Pre-POEM			Post-POEM
	Group 1: Male, year < 40 (n = 111)	Group 4: Female, year < 40 (n = 96)	P value	Group 1: Male, year < 40 (n = 111)	Group 4: Female, year < 40 (n = 96)	P value
Eckardt scores
Dysphagia			0.744			0.772
0	0	1		54	44
1	9	9		49	48
2	17	17		4	2
3	85	69		4	2
Regurgitation			0.535			0.722
0	13	10		78	71
1	25	30		29	24
2	34	24		2	0
3	39	32		2	1
Chest pain			0.394			0.147
0	54	36		78	59
1	39	43		31	37
2	12	10		1	0
3	6	7		1	0
Weight loss			0.450			0.665
0	19	22		109	93
1	19	14		2	3
2	30	31		0	0
3	43	29		0	0
Total Eckardt scores (median IQR)	7.17 (6, 9)	6.99 (5, 9)	0.411	1 (0, 2)	1 (0, 2)	0.611
Chicago classification	n = 97	n = 82	0.370	n = 97	n = 82	0.370
1	17	10		17	10
2	73	69		73	69
3	7	3		7	3
HRM (median IQR)
LESP, mmHg (median IQR)	29.5 (20.7, 38.5)	32.0 (22.8, 40.7)	0.252	13.8 (8.1, 18.5)	11.8 (8.1, 21.7)	0.889
IRP, mmHg (median IQR)	24.1 (17.9, 31.4)	26.1 (19.4, 33.8)	0.168	6.4 (5.2, 12.4)	10.0 (5.3, 16.6)	0.452
Length of LES, cm (median IQR)	2.5 (2.0, 3.0)	2.6 (2.0, 3.2)	0.351	1.9 (1.9, 2.6)	1.7 (1.4, 2.4)	0.374
Iodipin column, mm (median IQR)
Height	93.3 (65.1, 127.5)	88.8 (52.1, 156.5)	0.692	54.8 (44.6, 92.4)	46.4 (17.5, 94.3)	0.745
Diameter	49.1 (36.2, 59.7)	41.1 (31.4, 53.6)	0.746	28.6 (21.8, 44.5)	21.0 (10.9, 30.2)	0.230

IQR: Interquartile range; POEM: Peroral endoscopic myotomy; HRM: High-resolution manometry; LESP: Lower esophageal sphincter pressure; IRP: Integrated relaxation pressure; LES: Lower esophageal sphincter.

Table 4 Comparison of clinical characteristics between male and female subgroups (40 ≤ year < 60)

Variables	Pre-POEM			Post-POEM
	Group 2: Male, 40 ≤ year < 60 (n = 101)	Group 5: Female, 40 ≤ year < 60 (n = 136)	P value	Group 2: Male, 40 ≤ year < 60 (n = 101)	Group 5: Female, 40 ≤ year < 60 (n = 136)	P value
Eckardt scores
Dysphagia			0.270			0.862
0	0	0		43	62
1	15	14		51	67
2	19	19		3	4
3	67	103		4	3
Regurgitation			0.680			0.774
0	17	26		61	88
1	19	23		35	43
2	38	43		5	5
3	27	44		0	0
Chest pain			0.001			0.236
0	64	56		80	96
1	28	51		20	39
2	9	20		1	1
3	0	9		0	0
Weight loss			0.733			0.865
0	23	28		97	130
1	11	21		4	6
2	31	37		0	0
3	36	50		0	0
Total Eckardt scores (median IQR)	6.5 (5, 8)	7.1 (5, 9)	0.029	1 (0, 2)	1 (0, 2)	0.632
Chicago classification	n = 83	n = 108	0.430	n = 83	n = 108	0.430
1	13	11		13	11
2	63	90		63	90
3	7	7		7	7
HRM (median IQR)
LESP, mmHg (median IQR)	25.5 (20.6, 36.6)	33.2 (23.9, 43.5)	0.001	14.2 (10.9, 18.3)	16.6 (11.8, 21.5)	0.092
IRP, mmHg (median IQR)	21.6 (16.2, 27.1)	25.5 (20.2, 33.3)	0.003	9.4 (5.4, 15.3)	11.1 (8.6, 15.1)	0.266
Length of LES, cm (median IQR)	2.6 (2.0, 3.0)	2.5 (2.0, 3.0)	0.795	2.0 (1.7, 2.2)	1.8 (1.5, 2.9)	0.126
Iodipin column, mm (median IQR)
Height	81.3 (51.9, 106.6)	99.9 (68.7, 141.1)	0.061	47.8 (17.9, 84.9)	59.1 (42.2, 82.6)	0.645
Diameter	50.8 (38.2, 70.3)	42.3 (31.8, 55.7)	0.397	20.2 (14.1, 30.8)	24.8 (19.4, 39.5)	0.430

IQR: Interquartile range; POEM: Peroral endoscopic myotomy; HRM: High-resolution manometry; LESP: Lower esophageal sphincter pressure; IRP: Integrated relaxation pressure; LES: Lower esophageal sphincter.

Table 5 Comparison of clinical characteristics between male and female subgroups (year ≥ 60)

Variables	Pre-POEM			Post-POEM
	Group 3: Male, year ≥ 60 (n = 26)	Group 6: Female, year ≥ 60 (n = 56)	P value	Group 3: Male, year ≥ 60 (n = 26)	Group 6: Female, year ≥ 60 (n = 56)	P value
Eckardt scores
Dysphagia			0.663			0.295
0	0	4		14	32
1	4	7		9	21
2	7	14		1	3
3	15	31		2	0
Regurgitation			0.307			0.857
0	4	8		19	37
1	9	9		5	15
2	5	15		2	4
3	8	24		0	0
Chest pain			0.874			0.243
0	14	28		23	42
1	7	18		3	14
2	3	4		0	0
3	2	6		0	0
Weight loss			0.918			0.378
0	7	12		24	54
1	5	12		1	0
2	6	16		1	1
3	8	16		0	1
Total Eckardt scores (median IQR)	6.38 (5, 8.25)	7.0 (5, 8)	0.605	1 (0, 2)	1 (0, 2)	0.076
Chicago classification	n = 19	n = 48	0.195	n = 19	n = 48	0.195
1	6	8		6	8
2	13	35		13	35
3	0	5		0	5
HRM (median IQR)
LESP, mmHg (median IQR)	24.1 (11.2, 30.4)	31.6 (24.6, 39.4)	0.032	10.0 (7.9, 20.8)	16.6 (5.6, 21.7)	0.699
IRP, mmHg (median IQR)	16.7 (10.4, 22.8)	25.2 (17.3, 30.6)	0.028	10.7 (1.4, 15.2)	13.9 (5.8, 18.0)	0.546
Length of LES, cm (median IQR)	2.4 (1.9, 3.7)	2.6 (2.0, 3.3)	0.616	1.6 (1.5, 3.0)	2.1 (1.7, 2.7)	0.697
Iodipin column, mm (median IQR)
Height	84.9 (57.3, 133.4)	91.4 (67.8, 152.6)	0.638	41.2 (39.4, 89.8)	59.4 (38.0, 101.9)	0.688
Diameter	42.5 (32.4, 96.8)	36.1 (28.5, 50.7)	0.395	28.3 (27.6, 36.9)	32.3 (17.3, 35.8)	0.961

IQR: Interquartile range; POEM: Peroral endoscopic myotomy; HRM: High-resolution manometry; LESP: Lower esophageal sphincter pressure; IRP: Integrated relaxation pressure; LES: Lower esophageal sphincter.

Table 6 Comparison of improvement in Eckardt scores between male and female subgroups

Improved scores	Male (n = 238)	Female (n = 288)	P value	Improved scores	Male (n = 238)	Female (n = 288)	P value
Dysphagia				Chest pain
-2	1	0	0.567	-2	0	0	0.043
-1	1	3		-1	14	7
0	18	22		0	150	159
1	44	54		1	53	84
2	103	108		2	16	29
3	71	101		3	5	9
Regurgitation				Weight loss
-2	1	1	1.000	-2	0	1	0.741
-1	9	9		-1	1	0
0	49	49		0	50	65
1	60	60		1	37	46
2	70	70		2	65	86
3	49	49		3	85	90