By
Ahmad Younis
Professor of Thoracic Medicine
Mansoura Faculty of Medicine

Gastroesophageal reflux disease (GERD
)
A condition in which the stomach contents (food or liquid) leak backwards from the stomach into the esophagus.
This action can irritate the esophagus, causing heartburn and other symptoms.
Once food is in the stomach, a ring of muscle fibers prevents food from moving backward into the esophagus. These muscle fibers are called the lower esophageal sphincter.
If this sphincter muscle doesn't close well, food, liquid, and stomach acid can leak back into the esophagus.

Not only can stomach acid in the esophagus cause heartburn, but it can also cause ulcers , strictures of the esophagus, hoarseness, chronic pulmonary disease, and Barrett's esophagus (a change in the lining of the esophagus that increases the risk of developing cancer of the esophagus).

•

The upper esophageal sphincter
•
(UES) is a bundle of muscles at the top of the esophagus. The muscles of the UES are under conscious control, used when breathing, eating, belching, and vomiting. They keep food and secretions from going down the windpipe.

The aim of this work was to assess the frequency of GERD in patient with OSAS and to assess the relationship of severity of GERD to the severity of OSAS.

Patients and methods: This study included 30 OSAS patients and 20 controls. The patients and controls were subjected to the following. thorough history taking, with stress on symptoms of GERD, symptoms of OSAS, clinical examination, chest x-ray and full-night polysomnography and 24 hour pH monitoring. .

Mean age
Mean BMI
Sex
Male
Female
Table (1): Demographic data of patients with
OSAS versus Controls
Patients with OSA (n
= 30)
56.2 ± 3.48
31.10 ± 1.13
18 (60%)
12 (40%)
Controls
(n = 20)
55.5 ± 2.14
30.49 ± 1.39
14 (70%)
6 (30%)
Statistics t = 0.803
P = 0.426
t = 1.701
P = 0.095

2 = 0.521
P = 0.470

Table (2): GERD symptoms in patients with
OSAS versus Controls
Heart burn
Regurgitation
Dysphagia
Patients with
OSAS (n = 30)
No %
18 60
11 36.7
3 10
Controls (n = 20)
No %
4 20
2
0
10
0
Statistics

2 = 7.792
P = 0.005

2 = 4.435
P = 0.035

2 = 2.128
P = 0.145

Table (3): Variables of 24 hours pH monitoring in patients with OSAS versus controls
% time pH < 4 in supine position
% time pH < 4 in upright position
Total % time pH < 4
Number of episodes (pH < 4)
Number of episodes > 5 min
Longest episode
Demeester score
Patients with
OSAS (n = 30)
2 (0.8 – 18)
2.5 (0 – 7)
2 (0.7 – 10.9)
41 (10 – 172)
1 (0 – 8)
6 (1 – 32)
10.55 (3.7 – 68)
Controls (n = 20)
1 (0.2 – 10)
0.55 (0 – 4)
1 (0.2 – 6.2)
29 (7 – 172)
0 (0 – 1)
2.5 (1 – 7)
6 (1 – 29)
Statistics
U = 154.0
P = 0.003
U = 169.0
P = 0.009
U = 169.5
P = 0.009
U = 182.5
P = 0.019
U = 176.
P = 0.009
U = 164.0
P = 0.007
U = 168.0
P = 0.009

Table (4): Frequency of GERD in patients with
OSAS versus Controls
GERD (De Me Master score > 14.72)
Without GERD (De
Master score < 14.72)
Patients with
OSAS (n = 30)
No %
12 40
Controls
(n = 20)
No %
2 10
18 60 18 90
Statistics

2 = 5.357
P = 0.021

Table (5): GERD symptoms in OSAS patients with GERD versus OSAS patients without
GERD
Heart burn
Regurgitation
Dysphagia
OSAS Patients with GERD
(n = 12)
N %
12 100
9 75
2 16.7
OSAS Patients without GERD
(n = 18)
N %
6 33.3
0
1
0
5.6
Statistics

2 = 13.333
P < 0.001

2 = 19.286
P < 0.001

2 = 0.988
P = 0.320

Multiple investigators noted the validity of establishing GERD on the basis of symptoms
Otolaryngol Head
Neck Surg 2006; 135: 253-7.
clinician typically diagnose and treat
• patients with GERD on just clinical ground, so in certain clinical situation, it can obviate the need for 24 hour PH monitoring.
Aliment Pharmacol Ther; 2005; 21(9):
1127-33.

Table (6): OSA symptoms in OSAS patients with
GERD versus OSAS patients without GERD
Snoring
Excessive daytime sleepiness
Morning headache
Nocturnal chocking
Witnessed apnea
OSAS Patients with
GERD
(n = 12)
N %
12 100
OSAS Patients without GERD
(n = 18)
N %
12 66.7
12
6
100
50
9
3
50
16.7
9
6
75
50
6
6
33.3
33.3
Statistics

2 = 5.00
P = 0.025

2 = 8.571
P = 0.003

2 = 3.810
P = 0.051

2 = 5.00
P = 0.025

2 = 0.833
P = 0.361

possible positive feedback effect of
GERD on the pathophysiology of OSAS
Arousals caused by reflux may increase daytime somnolence
• close connection between severity of GERD and score of Epworth sleepiness scale as an indicator of daytime somnolence. proton pump inhibitor will markedly
• improve symptoms of sleepiness and reflux symptoms in patients with documented
OSAS. Laryngoscope 2004; 114: 1525-28.
•

Table (7): Variables of polysomnography in OSAS patients with GERD versus OSAS patients without GERD
OSAS Patients with
GERD
(n = 12)
OSAS Patients without GERD
(n = 18)
Statistics
Sleep efficiency
AHI
Arousal index
Desaturation index
Average SaO2 < 90%
% total time SaO2 < 90%
% time in snoring
89.92 ± 1.51
37.58 ± 4.06
24.25 ± 3.77
19.08 ± 1.31
25.25 ± 3.57
3.54 ± 0.49
18.50 ± 0.90
95.39 ± 1.91
33.50 ± 5.23
14.89 ± 3.72
10.78 ± 1.52
14.56 ± 3.87
1.20 ± 0.62
7.50 ± 5.31
t = 8.321
P < 0.001
t = 2.403
P = 0.023
t = 6.713
P < 0.001
t = 15.481
P < 0.001
t = 7.643
P < 0.001
t = 11.561
P < 0.001
t = 8.611
P < 0.001

Repeated reflux causes tissue swelling and this contribute to further airway obstruction
• with subsequent snoring and nocturnal choking. So GERD and OSAS adversely affect the symptoms and severity of the comorbid condition.
GER may result in anamnestic short
• awakenings that lead to sleep fragmentation and feeling un-refreshed the next morning, dozing off and daytime sleepiness .
Gastroenterology 2003; 124: A-414

The AHI in OSAS patients with GERD was significant higher than OSAS patients without
GERD
This signify that the positive feedback of
•
GER on the pathogenesis of OSAS may occur by causing edema of the upper airway by the acidic reflux with subsequent more
AHI.

Table (8): Correlation of severity of OSAS, severity of arousal index and severity of percentage total sleep time SaO2 < 90% to severity of GERD
Severity of OSAS (AHI)
Severity of arousal index
Severity of % TST SoaO2 < 90%
Severity of GERD (De
Mesteer Score) r
0.329
P
0.076
0.785
0.901
< 0.001
< 0.001

Arousal index and subsequent decrease in sleep efficiency may be implicated in the pathogenesis of GERD
This was in accordance to Kerr et al who reported that arousals may trigger GERD by causing transient alteration in the pressure gradient across the lower esophageal sphincter. Chest 1992; 101:
1539-44.
GER occurs most commonly during the brief stages of arousals
• arousals precede transient lower esophageal sphincter relaxation
•
•

. This was in accordance of Termato et al who reported increased GER episodes during hypoxia due to an impaired swallowing function. Chest 1999; 116, 17-
21 .
•

The severity of OSAS (AHI) showed no significant correlation with severity of GERD
(De Mesteer Score)
Morse et al reported that, objective
• correlation between OSA and GERD which may suggest that both are common entities sharing similar risk factors but may not to be causally linked. Clin Gastro-enterol
Hepatol 2004; 2: 761-768.

When acidification of the lower esophagus occur in patients with OSA, it is probably caused by a combination of increased transdiaphragmatic pressure gradient and coexisting pathology of lower esophageal sphincter causing incomplete closure.
GER is not caused by OSA but may be facilitated by it provided that there is already abnormal pathology in the lower esophageal sphincter
•
•

severity of OSA which is defined as higher score of
AHI, does not reflect the magnitude of respiratory effort during obstruction
. Also the upper airway resistance syndrome • which is associated with respiratory effort is not included in the AHI, therefore it is not easy to conclude that the occurrence of GER is related to the number of AHI rather than the respiratory effort during each breathing cessation period.
Beside the respiratory effort, repetitive stimulation of lower esophageal sphincter via phrenoesophageal ligament may also be linked with a threshold value of respiratory effort.

Conclusion: We can conclude from this study that GERD occur more common in OSAS patients as compared to controls (40% versus
10%) .
There were significantly positive correlation between arousal index and hypoxemic index with severity of GERD (DeMeesre score ) while no correlation exist between severity of
OSAS (AHI) and severity of GERD (DeMeesre score ).

It is recommended for sleep specialist to inquire about
GERD symptoms in patients with OSAS as it is a common problem .
Also gastroenterologists must inquire about OSAS symptoms in patients with GERD especially those not responding to proton pump inhibitor .