Table 2.

Outcome of 24-hour pH-impedance monitoring of treated achalasia patients with (RS+) and without reflux symptoms (RS−)

	Patients with reflux symptoms (RS+)	Patients without reflux symptoms (RS−)	P value
	(n=19)	(n=19)
24-hour pH-impedance monitoring
Acid exposure time (AET: % of time pH <4; mean (95% CI))
Total	13.8 (6.7 to 20.9)	10.9 (4.4 to 17.3)	0.53
Upright	10.9 (4.4 to 17.4)	6.6 (2.6 to 10.6)	0.24
Supine	17.7 (7.9 to 27.5)	16.4 (4.1 to 28.8)	0.86
Pathological acid exposure (AET pH <4 in >6%; n (%))	14 (74)	10 (53)	0.18
Acidification patterns (% of time; mean (95% CI))
Acid reflux with normal clearance	0.2 (0.06 to 0.28)	0.09 (0.01 to 0.16)	0.39
Acid reflux with delayed clearance	6 (0.94 to 11.0)	3.4 (−0.34 to 7.18)	0.051
Acid fermentation	6.6 (2.96 to 10.2)	1.8 (−0.45 to 4.10)	0.03
Stasis of ingested acidic food	2.2 (−0.04 to 4.55)	7.6 (−0.13 to 15.3)	0.18
Unclassified	1.8 (−0.49 to 4.11)	0.01 (−0.02 to 0.04)	0.11
No of acidification events (median (IQR))
Acid reflux with normal clearance	1 (0–2)	0 (0–1)	0.11
Acid reflux with delayed clearance	1 (0–3)	0 (0–1)	0.07
Acid fermentation	1 (0–3)	0 (0–0)	0.002
Stasis of ingested acidic food	0 (0–1)	0 (0–2)	0.54
Unclassified	0 (0–1)	0 (0–0)	0.008
No of patients per acidification pattern (n (%))
Acid reflux with normal clearance	10 (53)	5 (26)	0.1
Acid reflux with delayed clearance	12 (63)	6 (32)	0.051
Acid fermentation	13 (68)	4 (21)	0.004
Stasis of ingested acidic food	6 (32)	8 (42)	0.5
Unclassified	8 (42)	2 (11)	0.03
No of symptoms (median (IQR))	4 (3–5)	0 (0–2)	<0.001
Baseline impedance (Ω; median (IQR))
Proximal	2327 (1853–2836)	2638 (1659–3108)	0.93
Distal	487 (69–696)	476 (338–741)	0.84

AET, acid exposure time.