Oral neuromuscular training relieves hernia-related dysphagia and GERD symptoms as effectively in obese as in non-obese patients

Abstract

Background: Many physicians insist patients lose weight before their hiatal hernia (HH) condition and related symptoms including intermittent esophageal dysphagia (IED) and gastroesophageal reflux disease (GERD) can be treated, but it is not proven that body mass index (BMI) has an impact on exercise-based treatment of HH-related symptoms.
Aims/Objectives: To investigate whether BMI has significance on IQoro® neuromuscular training (IQNT) effectiveness in treating HH-related symptoms.
Material and Methods: Eighty-six patients with sliding HH and enduring IED and GERD symptoms, despite proton pump inhibitor medication, were consecutively referred for 6 months’ IQNT comprising 11/2 minutes daily. They were grouped by BMI which was recorded before and after IQNT, as were their symptoms of IED, reflux, heartburn, chest pain, globus sensation, non-productive cough, hoarseness, and misdirected swallowing. They were also assessed on food swallowing ability, water swallowing capacity and lip force both before and after treatment.
Results: After IQNT, all BMI groups showed significant improvement (p < .001) of all assessments’ and symptoms; and heartburn, cough and misdirected swallowing were significantly more reduced in the severely obese.
Conclusions and significance: IQNT can treat HH-related IED and GERD symptoms as successfully in moderately or severely obese patients as in those with normal bodyweight.

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Oral neuromuscular training relieves hernia-
related dysphagia and GERD symptoms as
effectively in obese as in non-obese patients
Thomas Franzen, Lita Ingrid Tibbling & Mary Karin Hägg
To cite this article: Thomas Franzen, Lita Ingrid Tibbling & Mary Karin Hägg (2019): Oral
neuromuscular training relieves hernia-related dysphagia and GERD symptoms as effectively in
obese as in non-obese patients, Acta Oto-Laryngologica, DOI: 10.1080/00016489.2018.1503715
To link to this article: https://doi.org/10.1080/00016489.2018.1503715
Published online: 10 Jan 2019.
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RESEARCH ARTICLE
Oral neuromuscular training relieves hernia-related dysphagia and GERD
symptoms as effectively in obese as in non-obese patients
Thomas Franzen
a
, Lita Ingrid Tibbling
b
and Mary Karin H€
agg
c
a
Experimental Medicine, Surgery, Link€
oping University, Vrinnevi Hospital, Norrk€
oping, Sweden;
b
Experimental Medicine, Surgery, Link€
oping
University, University Hospital, Link€
oping, Sweden;
c
Speech and Swallowing Centre, ENT, Hudiksvall Hospital, Hudiksvall, Sweden
ABSTRACT
Background: Many physicians insist patients lose weight before their hiatal hernia (HH) condition and
related symptoms including intermittent esophageal dysphagia (IED) and gastroesophageal reflux dis-
ease (GERD) can be treated, but it is not proven that body mass index (BMI) has an impact on exer-
cise-based treatment of HH-related symptoms.
Aims/Objectives: To investigate whether BMI has significance on IQoroV
Rneuromuscular training
(IQNT) effectiveness in treating HH-related symptoms.
Material and Methods: Eighty-six patients with sliding HH and enduring IED and GERD symptoms,
despite proton pump inhibitor medication, were consecutively referred for 6 months’IQNT comprising
11/2 minutes daily. They were grouped by BMI which was recorded before and after IQNT, as were
their symptoms of IED, reflux, heartburn, chest pain, globus sensation, non-productive cough, hoarse-
ness, and misdirected swallowing. They were also assessed on food swallowing ability, water swallow-
ing capacity and lip force both before and after treatment.
Results: After IQNT, all BMI groups showed significant improvement (p<.001) of all assessments’and
symptoms; and heartburn, cough and misdirected swallowing were significantly more reduced in the
severely obese.
Conclusions and significance: IQNT can treat HH-related IED and GERD symptoms as successfully in
moderately or severely obese patients as in those with normal bodyweight.
ARTICLE HISTORY
Received 28 June 2018
Revised 11 July 2018
Accepted 18 July 2018
KEYWORDS
BMI; GERD; hiatal hernia; lip
force; neuromuscular
training; reflux; obesity; oral
screen; swallowing capacity;
visual analogue scale
Introduction
Many physicians have considered obesity a cause of gastroe-
sophageal reflux disease (GERD) [1], and many more have
advised that treatment of GERD patients will be less suc-
cessful if they are severely overweight. Over time, research
into the pathophysiology of GERD has been characterized
by differing opinions on these subjects [1–9], and reports
describing that obesity per se predisposes to GERD have
been variously both supported and questioned [2]. Clinical
treatment effort for obese patients with GERD has been
focused on weight loss [3]. Understanding the pathophysi-
ology of GERD is important for future targets of therapy
[10], given that proton pump inhibitor-refractory GERD
symptoms are an increasing problem [11]. There is a clear
need for clarity on the effectiveness of treatment for GERD
and other hiatal hernia (HH) symptoms in the over-
weight population.
Recent studies [12,13] using esophageal high-resolution
manometry (HRM) show significant improvement in HH
patients, in GERD, esophageal retention symptoms, misdir-
ected swallowing, and significantly increased pressure in the
diaphragmatic hiatus after IQoro
V
R
(Figure 1) neuromuscular
training (IQNT). It has not been established however
whether there is a difference in the improvement rate
between obese and normal-weight patients with these symp-
toms when treated with IQNT. The present study therefore
aimed to investigate whether body mass index (BMI) has
any impact on IQNT results in HH-related intermittent
esophageal dysphagia (IED) and other GERD symptoms.
Materials and methods
Study population
A total of 86 adult patients (46 women and 40 men,
Table 1) with a verified HH (Figure 2A) and long-standing
IED and other GERD symptoms were consecutively referred
during 2014–2016 to an otorhinolaryngological clinic for
IQNT, 30 s 3-times per day in 6 months. Before entry into
the study, a HH without any esophageal stenosis was con-
firmed in each patient by radiology or gastroscopy. A test of
the orofacial muscle function (OFMT) [12] including the
cranial nerves’status (the intra- and inter-rater reliability of
the test has a high kappa coefficient of 0.90) [12], an oral
sensory test (OST) [12], and a velopharyngeal closure test
(VCT) [12] were performed in order to exclude symptoms
of any central nervous lesion. Patients with neurological dis-
eases were excluded. The patients were partitioned into
three groups according to BMI [1] at the start of the study:
CONTACT Mary Karin H€
agg mary.hagg@regiongavleborg.se Speech and Swallowing Centre, ENT, Hudiksvall Hospital, Hudiksvall 824 81, Sweden
ß2018 Acta Oto-Laryngologica AB (Ltd)
ACTA OTO-LARYNGOLOGICA
https://doi.org/10.1080/00016489.2018.1503715

Group A, normal weight, BMI <25 (n¼37: 19 women of
median age 68 years, 18 men of median age 72 years);
Group B, moderately obese, BMI 25–29 (n¼28: 16 women
of median age 59 years, 12 men of median age 56 years);
Group C, severely obese, BMI 30-37 (n¼21: 11 women of
median age 52 years, 10 men of median age 70 years). All
patients had received PPI medication for at least a median
3-year period (Table 1) and were still on this medication at
the start of the study. All patients were interviewed by tele-
phone 2–3 times during the six-month IQNT period in
order to check training compliance. Patients’BMI was cal-
culated at entry to the study and at completion of the
IQNT. Similarly, a self-assessed questionnaire regarding IED
and GERD symptoms [14] was recorded, and the patients’
ability to swallow food was self-assessed from 0 (normal) to
100 mm (total inability) on a visual analogue scale (VAS)
[15] on both occasions. Timed water swallowing capacity
test (SCT, ml/s) [12] and a lip force test (LFT, Newton) [12]
were performed at baseline and at end of training to con-
firm training compliance.
Self-assessment IED and GERD symptoms
All patients were required to complete a pre- and a post
training questionnaire regarding their IED and GERD
symptoms [14](Figure 2A;Table 2) scored from 0 to 3
(0 ¼none, 1 ¼slight, 2 ¼moderate, and 3 ¼severe). The
eight symptoms were defined as follows: IED ¼intermittent
sensation of solid food retention in the chest at swallowing;
reflux ¼acid regurgitation; heartburn ¼burning sensation in
the chest; chest pain ¼substernal pain at meals; Globus sen-
sation ¼sensation of a lump in throat; cough ¼irritating
and dry cough; hoarseness ¼husky voice; misdirected
swallowing ¼cough when swallowing is the clinical symp-
tom as well as a diagnosis by esophageal HRM.
IQoro
V
R
neuromuscular training (IQNT)
The IQoro
V
R
neuromuscular training (IQNT) device manu-
factured of acrylic is crescent-shaped, and convex in both
the vertical and horizontal planes (Figure 1). The surface is
rigid, with raised dimples interfacing with the inside of the
lips; and has a stable handle (Figure 1). The design makes it
universally suitable for varying bite and jaw anatomies.
IQoro
V
R
is located pre-dentally—behind the lips and in front
of the teeth –the patient grips the handle, presses the lips
firmly together and applies a horizontal forward pulling
force for 5 to maximally 10 s whilst resisting with the sealed
lips. The exercise is repeated three times per session, with a
3-s rest between each pull. This three-pull session is
repeated three times daily, preferably before mealtimes.
IQoro
V
R
(Figure 1), placed behind the lips, immediately
triggers sensory input by stimulating the intra-oral mem-
branes (n V), [12]. The sensory-motor reflex arc is engaged
by the stimuli conducted by the afferent nerve pathways to
the brain stem and the cortex and, in turn, the efferent sig-
nals transmitted from the brain stem to the muscles—the
natural neurological process [16]. The relevant muscles are
also activated by the mechanical flexing initiated by the
Figure 1. Image of IQoro
V
R
, a medical device for Neuromuscular Training
(IQNT). This image is kindly provided by MYoroface AB.
Table 1. Age, gender, symptom duration, and BMI in groups
A, B, and C.
Items Group A; n¼37 Group B; n¼28 Group C; n¼21
Median age 69 years (20–85) 57 years (22–85) 62 years (44–87)
Gender 19 women, 18 men 16 women, 12 men 11 women, 10 men
GERD symptom duration 5 years (1–75) 6 years (1–15) 3 years (1–29)
BMI before/after IQNT 23 (17–24)/23 (20–25) 28 (26–29)/27 (24–29) 33 (30–37)/31 (27–38)
Ranges in parentheses. BMI and GERD: median values; IQNT: Neuromuscular training with an oral IQoro
V
R
.
Figure 2. (A) Sliding hiatal hernia. When swallowing, the longitudinal esopha-
geal muscles contract and shorten which provokes the upper part of the stom-
ach to slide up through the hiatal canal. This causes difficulties with opening
the PES and with gastroesophageal reflux.This image is kindly provided by
MYoroface AB. (B) Effect of IQNT. Recent studies [12,13] show significant
improvement in symptoms in hiatal hernia patients after IQoro
V
R
Neuromuscular
Training (IQNT). Esophageal high-resolution manometry shows significantly
increased pressure in the diaphragmatic hiatus after the treatment.This image
is kindly provided by MYoroface AB.
2 T. FRANZEN ET AL.

IQoro
V
R
traction effect and the ensuing low-pressure thus
created [12]. The entire chain of striated muscles from the
lips to the upper third of the esophagus, and then to
the diaphragm, are activated by both the neurological and
the mechanical processes, whilst the smooth muscle is acti-
vated solely by the neurological commands from the sen-
sory-motor reflex arc [17]. The positive results of this
complex sensory-motor activity support earlier findings that
IQNT improves lip force (LF) and swallowing capacity (SC)
[12,18] and strengthens the striated muscles around the hia-
tal canal (Figure 2B) and improves hiatal competence simi-
larly to HH surgery [19].
Statistical analysis
A professional statistician from Uppsala Clinical Research
Centre (UCR) was involved and the Good Clinical Practice
(GCP) was used to consolidate all study data and for all
analyses, which were performed according to the initial
protocol. The Mann–Whitney U-test was used for compari-
son of all symptoms: BMI, self-assessment IED and GERD
symptoms, VAS, SCT, and LFT between the three BMI
groups. The Wilcoxon signed rank test was used for com-
parison of symptoms and investigation parameters within
the groups. p<.05 was considered significant. All statistical
analyses were performed using SAS version 9.1 software
(SAS Institute, Inc., Cary, NC).
Study design
This study is a prospective, therapeutic and clinical study
investigating whether BMI has an impact on IQNT’s effect
on HH-related IED and GERD symptoms.
Ethical considerations
The 86 patients in this study were referred to a swallowing
centre, as part of an otorhinolaryngological department for
the investigation and treatment of IED and GERD symp-
toms. They were examined and treated according to normal
practice and therefore, no ethical considerations arose. The
study was performed according to the Helsinki declaration.
Results
After IQNT, all symptom scores were significantly improved
or reduced within all three BMI groups (Table 2) and there
was no significant change of median BMI in any of the
groups (Table 1). At entry into the study, there were no sig-
nificant differences in IED and GERD symptom severity
(Table 2) between the three BMI groups except that heart-
burn and cough were significantly more common in Groups
B and C, and that misdirected swallowing was significantly
more common in Group C. No significant difference in self-
assessed IED and GERD symptom improvement was found
between the three BMI groups except for heartburn, cough
and misdirected swallowing which were significantly
(p<.01) more reduced in obese patients (Group C) than in
normal bodyweight patients (Group A; Table 2). In all BMI
groups IQNT provided significant improvement (p<.0001)
of median values of VAS score, SCT, and LFT (Table 3)
with no significant difference between the BMI groups
except for the value of SCT, which was significantly
(p<.01) more improved in Group C than in Group A, and
for the value of LFT, which was significantly (p<.05) more
improved in Group B than in Group A (Table 3). At entry
Table 2. Mean symptom scores in groups A, B, and C at entry (E) and after IQNT and p-value changes between group A/B, group A/C, and group B/C at entry
(E) and after IQNT.
GERD Group A Group B Group C Groups A versus B Groups A versus C Groups B versus C
Symptoms E (% Sympt) E (% Sympt) E (% Sympt) E, p-value E, p-value E, p-value
After (% Imp) n¼37 After (%Imp) n¼28 After (%Imp) n¼21 After p-value After p-value After p-value
Reflux (E) 1.3 (68) 1.5 (82) 1.8 (86) p<.587 p<.109 p¼.201
After IQNT 0.2 (100) 0.5 (96) 0.5 (100)
p<.0001 p<.0001 p<.0001 p<.581 p<.381 p¼.062
Heartburn (E) 0.9 (54) 1.4 (71) 1.6 (81) p<.043 p<.011 p¼.486
After IQNT 0.2 (85) 0.5 (95) 0.4 (100)
p<.0001 p<.0001 p<.0001 p<.185 p<.008 p¼.101
Chest pain (E) 1.0 (54) 1.4 (61) 1.2 (57) p<0.267 p<.528 p¼.750
After IQNT 0.2 (95) 0.3 (100) 0.2 (100)
p<.0001 p<.0001 p<.0005 p<.501 p<.384 p¼.840
Dysphagia (E) 2.3 (100) 2.3 (100) 2.3 (100) p<.897 p<0.772 p¼.719
After IQNT 0.6 (97) 0.8 (93) 0.6 (100)
p<.0001 p<.0001 p<.0001 p<.342 p<.842 p¼.505
Globus (E) 2.1 (92) 2.2 (89) 2.2 (91) p<.489 p<0.514 p¼.896
After IQNT 0.5 (100) 0.6 (96) 0.4 (100)
p<.0001 p<.0001 p<.0001 p<.483 p<.168 p¼.418
Cough (E) 1.1 (70) 1.7 (75) 1.9 (76) p<.044 p<.012 p¼.427
After IQNT 0.4 (96) 0.5 (91) 0.3 (100)
p<.0001 p<.0001 p<.0001 p<.184 p<.006 p¼.213
Hoarseness (E) 1.4 (76) 1.0 (54) 1.3 (62) p<.188 p<.847 p¼.406
After IQNT 0.4 (89) 0.3 (100) 0.2 (100)
p<.0001 p<.0001 p<.0002 p<.223 p<.726 p¼.202
Misdir sw (E) 1.2 (65) 1.4 (68) 2.1 (86) p<.530 p<0.007 p¼.038
After IQNT 0.2 (100) 0.3 (100) 0.3 (100)
p<.0001 p<.0001 p<.0001 p<.619 p<.005 p¼.030
Group A: (non-obese) BMI <25; Group B: (moderately obese) BMI ¼25–29; and Group C: (severely obese) BMI¼30–37. (% Symt): frequency of symptom; (% Imp):
frequency of improved or normalized symptoms; IQNT: Neuromuscular training with an oral IQoro
V
R
; Misdir sw: misdirected swallowing. p-values (Wilcoxon signed
rank test) refer to symptom improvements within groups after IQNT. p-values (Mann–Whitney U-test) refer to symptom changes between groups after IQNT.
ACTA OTO-LARYNGOLOGICA 3

into the study, there were no significant differences in VAS,
SCT, or LFT values between the BMI groups.
Discussion
This study shows that obese as well as non-obese patients,
with a sliding HH and with IED and PPI-resistant GERD
symptoms, can be equally and significantly improved by a
non-surgical IQNT intervention. At baseline, heartburn and
cough were significantly more prevalent in patients who
were overweight or obese, and misdirected swallowing was
significantly more common in patients with severe obesity.
However, symptoms of heartburn, cough, and misdirected
swallowing were significantly more relieved in these severely
obese patients. These findings are contradictory to the for-
mer belief that obesity is a handicap to successful treatment
of IED or GERD, or of weight loss being necessary before
treatment can be started. The results indicate that both IED
and GERD symptoms can be equally improved by IQNT
irrespective of normal or pathological BMI, and indeed that
improvement of some symptoms is even more successful in
the higher BMI categories. Additionally, Mora et al. [4] did
not find any correlation between the degree of obesity and
the severity of symptoms or objective tests for IED and
reflux. In another study, by Vakil et al. [5], PPI-treated
patients who achieved heartburn relief were similar across
BMI categories. The link between GERD and obesity has
also been called into question by other authors [20]. Three
earlier studies from 1995, 1996, and 2005 showed that being
severely overweight was not associated with an increased
prevalence of gastroesophageal reflux [6], that weight loss
did not improve the subjective or objective manifestations
of reflux [7] and that obesity was an independent risk factor
for GERD symptoms and erosive esophagitis [8].
GERD is primarily associated with heartburn and acid
regurgitation. At entry of this study, these symptoms were
present in all patients, despite their all being on a course of
PPI medication. Significantly, the acid symptoms were
greatly improved by IQNT even those in this study who had
GERD symptoms but were resistant to PPI treatment.
Moraes [11] has described nine possible explanations for
GERD refractory symptoms but did not consider impaired
function of the striated swallowing muscles. Irrespective of
which the cause was IQNT was shown in this study to pro-
mote significant improvement of all eight symptoms (Table
2) as defined in the self-assessed questionnaire regarding
IED and GERD symptoms. These symptoms were measured
in the same way at both baseline and at end-of-training,
and for all patients irrespective of BMI value.
The results achieved by IQNT reinforce the hypothesis
that oral neuromuscular training triggers the afferent reflex
arc up to the brainstem and brain cortex [16], and then pro-
motes the efferent reflex arc to activate both the striated and
smooth muscles [17]. The motoric effect is executed neuro-
logically via the Nucleus Ambiguus and the Nucleus Dorsalis
Nervi Vagi—both in the Formatio Reticularis—which are key
components in the normal swallowing process (Figure 2B)
[16,17]. BMI values appear to have no effect on the ability of
IQNT to bring about the improvement of GERD and IED
symptoms by both muscular and neurological improvements.
Conclusion
IQNT, a non-surgical treatment for IED and other GERD
symptoms in HH patients, is equally successful in treating
moderately- or severely obese patients as in treating suffer-
ers of normal weight. Obesity in itself does not therefore
seem to be a handicap in treating IED and other GERD
symptoms by IQNT.
Disclosure of interest
No potential conflict of interest was reported by
the authors.
ORCID
Thomas Franzen http://orcid.org/0000-0001-8661-2523
Lita Ingrid Tibbling http://orcid.org/0000-0003-4505-4750
Mary Karin H€
agg http://orcid.org/0000-0003-3923-5475
Table 3. Changes for SCT, LFT and VAS in groups A, B and C after IQNT, and difference between group A/B, group A/C, and group B/C at entry (E) and after
(a) IQST.
Group A Group B Group C Groups A versus B Groups A versus C Groups B versus C
n¼37 n¼28 n¼21
Median (95% CI) Median (95% CI) Median (95% CI) Median (95% CI) Median (95% CI) Median (95% CI)
Items p-value p-value p-value p-value p-value p-value
SCT (E) 13.5 (8.7 to 16.7) 10.0 (6.7 to 16.2) 15.0 (8.2 to 19.1) p<.900 P<.196 p<.895
ml/s (a) 17.3 (12.7 to 20.0) 18.7 (12.4 to 27.7) 21.7 (16.7 to 29.3)
Change 5.0 (3.3 to 5.7) 7.7 (3.7 to 10.3) 6.6 (4.2 to 10.4) 2.5 (0.2 to 5.3) 2.8 ( 0.6 to 5.1) 0.4 (3.3 to 3.4)
p<.0001 p<.0001 p<.0001 p<0.066 p<0.014 p<0.848
LFT (E) 31.0 (26.0 to 42.0) 35.5 (24.0 to 46.0) 38.0 (25.0 to 44.0) p<0.817 p<0.903 p<0. 192
N (a) 53.0 (48.0 to 60.0) 63.5 (55.0 to 80.0) 52.0 (45.0 to 68.0)
Change 20.0 (14.0 to 24.0) 28.0 (14.0 to 34.0) 18.0 (5.0 to 44.0) 8.0 ( 0.0 to 15.0) 0.0 (10.0 to 13.0) 6.0 (19.0 to 6.0)
p<.0001 p<.0001 p<. 0001 p<.048 p<.891 p<.196
VAS (E) 80.0 (60.0 to 80.0) 80.0 (70.0 to 80.0) 70.0 (60.0 to 80.0) p<.479 p<.616 p<.241
mm (a) 20.0 (0.0 to 25.0) 17.5 (10.0 to 20.0) 20.0 (10.0 to 25.0)
Change 50.0 (60.0 to 40.0) 56.0 (66.0 to 50.0) 50.0 (60.0 to 40.0) 5.0 (12.0 to 5.0) 0.0 (10.0 to 10.0) 6.0 (5.0 to 15.0)
p<.0001 p<.0001 p<.0001 p<.288 p<.844 p<.267
Group A: (non-obese) BMI <25; Group B: (moderately obese) BMI ¼25-29; and Group C: (severely obese) BMI ¼30–37. Median values, range in parentheses.
N: Newton; IQNT: Neuromuscular training with an oral IQoro
V
R
.p–values (Wilcoxon signed rank test) refer to symptom improvements within groups after IQNT.
p-values (Mann–Whitney U-test) refer to symptom changes between groups after IQST.
4 T. FRANZEN ET AL.

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