Keywords
deglutition disorders - mentally disabled persons - video endoscopy
Introduction
Feeding, deglutition and breathing are fundamental activities for the survival and
well-being of humans, and, once altered, they may raise morbidity and mortality rates.
Feeding comprises a set of systems, from choosing the food up to its insertion in
the oral cavity, chewing and swallowing. Patients with physical or mental disabilities
deviate from this set of systems, leading to a possible compromise of their feeding
pattern.[1]
The deglutition process involves bone, muscle, cartilaginous and neural structures
of the digestive and breathing tracts, working in a coordinated manner to send the
food bolus down to the stomach. Any kind of imbalance in this mechanism may lead to
impairments of its function. This process can be divided into four stages: preoral,
oral (or transport), pharyngeal and esophageal. The first two stages are voluntary,
while the pharyngeal and esophageal stages are involuntary.[2]
The act of swallowing is a vital function to human beings. Despite the fact that it
seems simple, it is a highly complex and dynamic process, whose involved structures
and systems are akin to the act of breathing, thus being of extreme importance for
the nutrition of the organism as a whole. During deglutition, the food is transported
from the oral cavity down to the stomach, without the entry of any substance into
the airways, and for that the individual must have precise coordination, mainly between
the oral and pharyngeal stages.[3]
Dysphagia is defined as difficulty in swallowing the ingested food in the path from
the orophrarynx down to the stomach, which may be associated with other symptoms,
such as regurgitation, tracheobronchial aspiration, retrosternal pain, pyrosis, hoarseness,
hiccups and odynophagia, and can compromise clinical, nutritional and/or social aspects
of the individual. It occurs whenever there is a lack of control in the coordination
of the breathing and feeding functions, and may occur as a result of neurological
alterations, either congenital or acquired, structural or functional, or even as a
result of morbid states.[4]
The broader definition of dysphagia includes abnormalities in all behavioral, sensory
and preliminary motor skills involved in the swallowing processes, as well as the
cognitive conscience, the visual recognition of food, and the physiological response
to the presence of food, such as the increase in salivation, which lead to the desire
and capacity of the patients to feed. Additionally, it is a multidimensional symptom
commonly dependent on morbidity, mortality and cost.[5]
Dysphagia symptoms may vary from individual to individual and over time in the same
person. An important clinical sign is aspiration, defined as the passage of material
below the level of the vocal folds, which is an important sign due to several reasons,
including the impact it might have on the health of the individual. However, aspiration
effects are hard to predict, as they do not equally affect all dysphagic individuals.[6]
It is estimated that, in the United States, between 300,000 and 600,000 individuals
with neurological diseases are annually affected by oropharyngeal dysphagia (OD),
generally patients with cerebrovascular diseases. Among these, 43 to 54% will suffer
with episodes of tracheal aspiration, 37% will develop pneumonia, and 3.8% will die
as a consequence of these episodes.[7]
The assessment of dysphagia may be performed using the clinical history of the patient
with the aid of complementary examinations, such as videofluoroscopy, surface electromyography,
pharyngoesophageal manometry, nasofibrolaryngoscopy and functional endoscopic evaluation
of swallowing. These examinations aid in the identification of the cause behind the
dysphagia, aspiration risks and oral feeding conditions by establishing the final
diagnosis and the most correct therapeutic conduct.[4]
In 1998, the first description of the fiberoptic endoscopic evaluation of swallowing
(FEES) procedure was published. Before the advent of optic fiber technology, the laryngoscopy
was performed with a mirror or direct invasive laryngoscopic instruments. This evolution
changed the practice of laryngoscopy, thus allowing a transnasal approach with a conscious
patient during the procedure and providing a vision of the vocal folds during natural
speech.[8]
Nasofibrolaryngoscopy and the functional endoscopic evaluation of swallowing provide
information regarding the airway structures and the swallowing process, also providing
a safe way to administer food to observe the propulsion process of the food bolus.[9]
The objective of the present study was to assess swallowing in institutionalized patients
with mental disability to determine the incidence and severity of dysphagia in this
population. As specific objectives, it was aimed to characterize the correlation with
dysphagia of degree of mental incapacity; and to correlate the degree of dysphagia
with the mental deficiency, age group, gender and population studied.
Method
The present study was approved by the Ethics in Research Committee under the CAAE
number 0121.0.132.000–09.
This was a cross-sectional study that analyzed 189 institutionalized adult patients
with mental disabilities and associated physical disabilities.
The subjects underwent a previous neuropsychological evaluation for mental disabilities,
which was performed by a multidisciplinary team. The disabilities were classified
as profound, severe, moderate and mild, according to the World Health Organization's
(WHO) International Statistical Classification of Diseases and Related Health Problems,
tenth revision (ICD-10).
In the present study, swallowing was analyzed by means of the functional evaluation
of swallowing using a Machida 3.2 mm flexible nasal fiberscope (Machida Endoscope
Co., Ltd., Chiba, Japan) without topic anesthesia, in order to preserve sensitivity.
The consistency of the following types of foods was tested: pasty, thickened fluid
and fluid. In order to better visualize the food inside the pharynx during and after
swallowing, a blue methylene dye was used. All patients were tested with 5 swallowings
for each consistency, starting with 5 ml and gradually increasing to 10 and 15 ml.
The following were observed: accumulation of saliva or food in the hypopharynx, nausea
and coughing reflexes, precocious escape (escape of food to the vallecula and pyriform
sinus before actual swallowing), laryngeal penetration (entry of material inside the
laryngeal vestibule above the vocal folds) and tracheal aspiration (passage of material
below the vocal folds).
The degree of dysphagia was classified according to the clinical endoscopic classification
for dysphagia:[10]
Normal swallowing (degree 0): normal swallowing without observable alteration during
the examination. Normal oral containment, observable reflexes, no stasis of saliva,
food and aspiration, less than three propulsion attempts to clear the food bolus.
Mild dysphagia (degree 1): small post-swallowing stasis, less than three propulsion
attempts to clear the food bolus, no nasal regurgitation and laryngeal penetration.
Moderate dysphagia (degree 2): moderate salivary stasis, higher postswallowing stasis,
more than three propulsion attempts to clear the food bolus, nasal regurgitation,
reduction of laryngeal sensitivity with penetration in the laryngeal vestibule, but
without laryngotracheal aspiration.
Severe dysphagia (degree 3): major salivary stasis, considerable worsening of postswallowing
residues, poor or no propulsion, nasal regurgitation, tracheal aspiration.
A statistical analysis was performed for tests with significance level, ordinal logistic
regression (LR) analysis and odds ratio (OR).
Results
The studied group consisted of a total of 189 patients, 101 (53.4%) of which were
female. The age of the patients ranged from 14 to 55 years old, with an average age
of 36.7 years (±9.6 years).
Most patients 120 (63.5%) had profound mental disability, 58 (30.7%) had severe disability,
9 (4.8%) had moderate disability, and 2 (1.1%) had mild disability. Considering that
only 2 patients had a mild degree of disability and that 9 patients had a moderate
degree of disability, a new category was created, called “mild or moderate disability”,
considering those 11 patients (5.8%), to better visualize the results and the validity
of the statistical analysis.
Most of the patients 169 (89.4%) presented dysphagia: 103 (54.5%) were severe cases,
46 (24.3%) were moderate cases, and 20 (10.6%) were mild cases ([Tables 1], [2] and [3]).
Table 1
Distribution of the degree of dysphagia by gender
Degree of dysphagia
|
Male
|
Female
|
n
|
%
|
n
|
%
|
Severe
|
46
|
52.3
|
57
|
56.5
|
Moderate
|
22
|
25.0
|
24
|
23.8
|
Mild
|
12
|
13.6
|
8
|
7.9
|
Normal
|
8
|
9.1
|
12
|
11.9
|
Table 2
Distribution of the degree of dysphagia by age groups
Degree of dysphagia
|
10–20 years old
|
21–30 years old
|
31–40 years old
|
41–50 years old
|
51–55 years old
|
n
|
%
|
n
|
%
|
n
|
%
|
n
|
%
|
n
|
%
|
Severe
|
6
|
66.7
|
28
|
66.7
|
35
|
54.7
|
27
|
42.8
|
7
|
63.7
|
Moderate
|
1
|
11.1
|
10
|
23.8
|
16
|
25.0
|
17
|
27.0
|
2
|
18.2
|
Mild
|
0
|
0.0
|
2
|
4.8
|
6
|
9.4
|
12
|
19.0
|
0
|
0.0
|
Normal
|
2
|
22.2
|
2
|
4.8
|
7
|
10.9
|
7
|
11.1
|
2
|
18.2
|
Table 3
Distribution of the degree of dysphagia by degree of mental disability
Degree of mental disability
|
Mild or Moderate
|
Severe
|
Profound
|
Degree of dysphagia
|
n
|
%
|
n
|
%
|
n
|
%
|
Severe
|
6
|
50.0
|
30
|
51.7
|
67
|
55.8
|
Moderate
|
3
|
0.0
|
16
|
27.6
|
27
|
22.5
|
Mild
|
0
|
0.0
|
5
|
8.6
|
15
|
12.5
|
Normal
|
2
|
50.0
|
7
|
12.1
|
11
|
9.2
|
According to the ordinal LR analysis, we observed that gender and degree of mental
disability (p = 0.450) did not present a significant influence in the level of dysphagia ([Table 4]).
Table 4
Results of ordinal logistic regression models
Model
|
Variable
|
Value
|
Standard error
|
p-value
|
Odds ratio
|
Gender
|
Gender
|
0.070
|
0.261
|
0.788
|
1.07
|
Age range
|
Age range
|
–0.305
|
0.135
|
0.024
|
0.74
|
Degree of disability
|
Degree of disability
|
–0.65
|
0.128
|
0.450
|
0.85
|
Age range, degree of disability, and interaction
|
Age range
|
1.326
|
0.642
|
0.039
|
3.77
|
Degree of disability
|
1.857
|
0.822
|
0.024
|
6.41
|
Interaction
|
–0.626
|
0.249
|
0.012
|
0.53
|
Age presented a significant influence in the level of dysphagia (p = 0.024), and with the increase in age there was an increase in the severity of dysphagia
among the age groups between 10 and 30 years old. The estimated OR was of 0.74, that
is, the increase in age group (from 10–20 years to 21–30 years, for example) increases
by 27% the odds of a patient presenting a more severe level of dysphagia.
The joint influence of three variables was evaluated (gender, age group and degree
of disability), and the interactions were assessed in pairs regarding the three variables
at the dysphagia level. Gender still had no significant influence on the degree of
dysphagia. The same applies to interactions between gender and age, and between gender
and mental disability.
We observed that the age group (p = 0.039), the degree of disability (p = 0.024) and the interaction between age group and the degree of disability (p = 0.012) presented a significant influence on the level of dysphagia ([Table 2]).
The effects of the interaction between age groups and the degree of disability in
the probability of presenting more or less severe dysphagia are shown in [Fig. 1]. For the age groups between 10 and 20 years old and between 21 and 30 years old,
the probability of presenting a more severe dysphagia increased with the increase
in the degree of disability. For the age group between 31 and 40 years old, the degree
of disability did not affect the level of dysphagia. On the other hand, for the age
groups between 41 and 50 years old and between 51 and 55 years old, the result is
the opposite. The increase in the degree of disability decreased the odds of presenting
a more severe dysphagia.
Fig. 1 Probability of dysphagia by age group and degree of disability.
Regarding the OR:
-
At the age group between 10 and 20 years old, the odds of presenting a more severe
dysphagia is 3.4 times higher when the degree of disability changes from mild or moderate
to severe, and 11.1 times higher when it changes from mild or moderate to profound.
-
Between 21 and 30 years old, the odds of presenting a more severe dysphagia is 1.8
times (80%) higher when the degree of disability changes from mild or moderate to
severe, and 3.3 times higher when it changes from mild or moderate to profound.
-
At the age group between 31 and 40 years old, the odds of presenting a more severe
dysphagia remains practically unaltered when the degree of disability changes from
mild or moderate to severe, and from mild or moderate to profound.
-
Between 41 and 50 years old, the odds of presenting a more severe dysphagia is 1.9
times higher when the degree of disability changes from mild or moderate to severe,
and 3.65 times higher when it changes from mild or moderate to profound.
-
At the age group between 51 and 55 years old, the odds of presenting a more severe
dysphagia is 3.57 times higher when the degree of disability changes from mild or
moderate to severe, and 12.76 times higher when it changes from mild or moderate to
profound.
Discussion
Hospitalized patients with neurological alterations, neurodegenerative diseases, head
and neck anatomic alterations, and/or breathing impairments have a higher risk of
developing OD.[4]
Concerning the feeding and nutrition of patients with special needs, few studies can
be found in the relevant literature. It is known that between 39 and 56% of the children
with chronic development issues, such as cerebral palsy (CP), Down syndrome and others,
have or will develop a swallowing disorder. The consequences of these disorders end
up leading to new health problems that aggravate the conditions of these individuals
and their capacity to adapt socially.[11]
The basic motor difficulty of these children may also affect the oral function, understood
as the motor and sensory aspects of the oral cavity and pharynx structures up to the
entrance of the esophagus. Therefore, it is known that these children belong to a
risk group when developing swallowing disorders or dysphagia, which is one of the
first signs of a neurological disorder.[11]
In patients with CP, there is a reduction in cerebral oxygenation, impairing areas
that command the swallowing action. Changes in the swallowing action may cause feeding
impairments. One of the difficulties found in dysphagia is the act of starting a correct
swallowing, as well as others, such as nasal regurgitation, lack of coordination in
tongue control, sialorrhea, lack of mobility in the laryngeal muscles, and undesired
events such as choking and coughing during meals, which may lead to cases of malnutrition,
dehydration and breathing problems. The role of chewing is not significant in these
patients, due to foods being swallowed whole, increasing the amount of energy spent
in the digestion of each meal. Thus, feeding with solid food is not the most recommended
form for most patients with motor and mental disorders.[2]
Performance conflicts in the motor and oral functions may lead to the appearance of
inabilities in each step of the swallowing procedure, with possible simultaneous interactions.
Chronic swallowing adulterations may lead to malnutrition, dehydration, aspiration
and pneumonia. Frequent signs observed in these cases are regurgitation, difficulty
to swallow saliva, coughing at the time of feeding, and breathing instability or apnea,
among others, which may cause the inability to eat certain types of food. A considerable
amount of time must be spent on feeding, and a special diet, different from the one
consumed by the rest of the family, is required. These symptoms end up causing stress
and anxiety to the parents, turning the act of eating into a complex, difficult, stressful
and unpleasant process.[11]
The usage of the concept of efficiency in OD must be understood as the capacity that
a therapeutic process has to produce beneficial effects in the dynamics of swallowing.
However, the efficiency is related to improvements in the overall status of the individual,
regardless of the permanence of the disorder, provided that procedures are implemented
to ensure a safe oral ingestion, the maintenance of the nutritional condition, and
the stabilization of pulmonary problems.[12]
To monitor OD, it is absolutely required to proceed to the clinical evaluation of
the swallowing associated with a videofluoroscopic or nasofibrolaryngoscopic instrumental
assessment of swallowing.[13]
In cases in which the neurological impairment is just mild, we can be observe that
the oral and motor disorders are generally restricted to the oral stage of swallowing,
with no impact on the overall clinical status. Thus, the rehabilitation of functional
patterns required for both speaking and swallowing is more easily achieved. However,
when the degree is either moderate or severe and there are intense motor, global and
oral alterations commonly associated with the presence of multiple disabilities, a
situation of dysphagia may appear, added to the alterations of the pathology.[7]
The incidence and severity of OD tend to worsen as the individual ages, and in a much
more aggravated manner in those individuals with neurological diseases, thus deteriorating
both the nutritional and breathing states, leading to malnutrition, pneumonia and
even death.[2]
We observed in the present study that gender did not affect the severity of the dysphagia.
In the present study, we observed that the interaction between age group and degree
of disability presented a significant influence in the level of dysphagia. It became
clear that the younger patients have higher odds of presenting a more severe dysphagia.
Stabilization occurs between 31 and 40 years old, and after this age the patients
present higher odds of having a less severe dysphagia.
The analysis demonstrated that with the increase in the degree of disability, the
level of dysphagia increased as well, except for patients between 41 and 55 years
old, in whom the increase in the degree of disability decreased the odds of incidence
of a more severe dysphagia. We can infer that the patients with more severe dysphagia
do not reach the older age groups due to breathing complications, which allows us
to understand that, at older age groups, we find patients with a milder dysphagia.
The analysis of dysphagia in patients with cerebral palsy is intended to warn the
medical staff of the requirement of a more individualized and customized treatment
of the patient, to promote more quality and functionality to the life of the patient.
Dysphagia is a symptom that involves several anatomic and functional alterations,
which must be addressed in a multidisciplinary manner. Several fields of expertise
in the field of health must work together to ensure the evaluation and the access
to all factors surrounding the issue, as well as take the required actions that enable
the control of the dysfunction, thus preventing potential complications, such as malnutrition,
dehydration and aspiration pneumonia.[14]
The patient who is clinically impaired by dysphagia still in the hospital environment
requires treatment from a multidisciplinary team formed by a speech therapist, physicians
from different areas of expertise, a physiotherapist, a nutritionist, a nurse, an
occupational therapist, and a psychologist.[15]
Dysphagia remains an important symptom with a poorly defined epidemiology. Some studies
suggest a prevalence rate between 16 and 22%. Other studies state that dysphagia will
become an important public health issue with increasing age. There are few studies
available on the impact of dysphagia on the quality of life of the patients.[16]
The diagnosis and treatment of dysphagia have the potential to decrease the morbidity
and mortality rates of patients with mental disability.
Conclusion
The study sample was characterized as mostly female, with profound mental disability,
with an average age of 36.7 years, and 89.4% of them presented dysphagia, mostly severe.
In the isolated analysis of each variable, there was no correlation between gender
and degree of mental disability concerning the level of dysphagia.
In the analysis of the interaction between age group and the degree of mental disability,
we verified that for age groups under 30 years old, the higher the degree of mental
disability, the higher the odds of severe dysphagia; for the age group between 31
and 40 years old, there was no influence between the degree of mental disability and
the severity of the dysphagia; and above 40 years old, the situation reversed, that
is, the higher the degree of mental disability, the higher the odds of presenting
a less severe dysphagia.