Keywords
depression - hearing loss - aging
Palavras-chave
depressão - perda auditiva - envelhecimento
Introduction
Aging is a global reality, even in the poorest countries. In Brazil, especially, the
process is occurring in a radical and rapid, indicating that in 2020, the country
occupies the sixth place in number of elderly[1]. This process causes a series of changes in functional systems, and gradually irreversible,
with intensification of sensory and motor limitations, as well as the onset or worsening
of chronic degenerative diseases[2].
The declining ability to hear in the elderly is called presbycusis. Studies show that
in Brazil the prevalence of hearing loss in this population varies between 36% and
81%[3]
[4]. Aging, however, cannot be considered the only factor that causes hearing loss,
since a series of negative factors intrinsic and extrinsic factors can cause or exacerbate
hearing disorders, such as the occupation of the individual, the use of ototoxic drugs,
exposure to noise made by individuals and diseases (diabetes, hypertension, atherosclerosis
- e.g.)[3]
[5]
[6].
Studies have shown that presbycusis begin in the third decade of life, and the effects
observed after the fifth decade[7]. Hearing loss is usually sensorineural, symmetric, descending with audiometric configuration
predominantly in men and women in the horizontal[8]
[9]. The degree varies from mild to moderately severe, and the hearing of men is more
affected than women. The worsening of hearing loss is directly related to increasing
age[6]
[8]
[10].
Presbycusis causes social unrest, emotional and psychological stress, with reduced
social life, increase in relationship problems with family, friends and work. These
disorders affect negatively the mobility and activities of daily living[11]
[12]
[13].
Among the psychological problems seen in elderly patients with hearing loss are depressions[12]
[14]
[15]
[16]
[17]. This association may be largely due to social isolation, as well hear is an important
prerequisite for social interaction[13]
[18]
Depression is one of the most common mental disorders in the elderly. Between 15%
and 30% of individuals in this group have depressive symptoms, and no treatment may
be associated with physical decline, illness, decreased quality of life and mental
decline[19]
[20]. Studies show that depression primarily affects the elderly (compared with groups
of adults and youth)[21], with higher prevalence in females[22]
[23]
[24].
Considering the theoretical assumptions described in the literature, which refer to
a relationship between hearing loss and depression, this study aims to determine the
association between the presence and degree of hearing loss and depressive symptoms
in a group of non-institutionalized elderly.
Method
This study was cross sectional, observational and prospective. The sample consisted
of individuals aged 60 years or more[25]. Among the inclusion criteria were: age within the age criteria, signing an informed
consent, absence of obstructive wax in the ear canal and completion of assessments
selected for the survey.
To conduct the study, subjects underwent audiological evaluation and screening of
depressive symptoms. The audiological evaluation consisted of pure tone audiometry,
performed on acoustic hood, a survey of hearing thresholds by air (from 250 Hz to
8000 Hz) and bone (500 Hz to 4000 Hz), using brand Interacoustics audiometer Model AD-28. There were also the speech audiometry (Percentage Index of
Speech Recognition and Speech Reception Threshold) and acoustic immittance measures.
Search for tympanometry and acoustic reflex, we used the middle ear analyzer brand
Interacoustics, model AT235.
The presence and degree of hearing loss were determined using the classification of
the World Health Organization, with the average hearing thresholds by air in the frequencies
of 500 Hz to 4000 Hz Mean values between -10 and dBHL 25dBNA indicate that the person
has normal hearing, and between 26dBNA 40dBNA, mild hearing loss, and between 41dBNA
60dBNA, moderate hearing loss, and between 61dBNA 80dBNA severe hearing loss and average
thresholds above 81dBNA, profound hearing loss. For this work we considered the mean
of the better ear[26].
Screening for depressive symptoms was done by the Geriatric Depression Scale (GDS)[27]. This instrument has been translated and validated in Brazil[28], consists of fifteen items, the individual being asked to mark yes or no after each
question. The application was done individually, in a waiting room, after hearing
evaluation.
According to the rules of interpretation of the GDS, with each answer that showed
a downward trend was attributed to (1) point. The assessment was made as follows[29]:
-
less than 5 points: no depressive symptoms;
-
between 5 and 10 points: mild to moderate depressive symptoms;
-
11 points or more: severe depressive symptoms.
After completion of the assessment was created a database for later quantitative statistical
analysis. Were considered statistically significant p values less than or equal to
0.05.
Descriptive analysis of quantitative variables was performed by calculating the absolute
frequencies, mean and standard deviation. To calculate the associations between the
presence / absence of hearing loss and depressive symptoms and degree of hearing loss
and level of depressive symptoms was performed using chi-square.
This research is part of the project 'Characterization of elderly patients in project
extension officer', adopted by the Ethics Committee of University Research (CER) protocol
as 125H.
Results
This research was carried out to verify the existence of an association between the
presence and degree of hearing loss and depressive symptoms in a group of non-institutionalized
elderly.
We evaluated 54 individuals from 60 to 84 years with a mean age of 70.4 ± 7.16 years,
26 (48.1%) were female and 28 (51.9%) males.
Regarding the hearing, according to data presented in [Table 1], was found hearing loss in most individuals in the sample. The degree of hearing
loss ranged from mild to moderate.
Table 1.
Presence and degree of hearing loss in the sample components.
|
n
|
%
|
Normal hearing thresholds
|
15
|
27.8
|
Mild hearing loss
|
17
|
31,5
|
Moderate hearing loss
|
22
|
40,7
|
Total
|
54
|
100
|
Legend: n = absolute values, % = percentages.
The data analysis of geriatric depression scale showed that of the 54 elderly patients,
25 subjects had depressive symptoms (46.3%), as shown in [Table 2].
Table 2.
Presence of depressive symptoms among the sample components.
Depressive symptoms
|
n
|
%
|
Absent
|
29
|
53,7
|
Mild to moderate
|
23
|
42,6
|
Severe
|
2
|
3,7
|
Total
|
54
|
100
|
Legend: n = absolute values, % = percentages.
The data presented in [Table 3] show that there was an association between hearing loss and depression (p = 0.016),
since, of 25 (46.3%) elderly with depression, 22 (40.7%) had hearing loss .When we
analyzed the association between the degree of hearing loss and depressive symptoms,
there was, however, a significant association (p = 0.18). It was noted, however, positive
trend in the severity of the signs of depression. That is, the greater the hearing
loss the greater the severity of the signs ([Table 4]).
Table 3.
The presence of hearing loss and depression in elderly individuals in the sample.
Hearing
|
Depressive symptoms
|
|
Present
|
Absent
|
|
n
|
%
|
n
|
%
|
Normal hearing thresholds
|
3
|
5,6
|
12
|
22,2
|
Hearing loss
|
22
|
40,7
|
17
|
31,5
|
Total
|
25
|
46,3
|
29
|
53,7
|
p = 0,016*
Legend: n = absolute values, % = percentage values, p = significance level.
Table 4.
Depressive symptomatology and degree of hearing loss.
Hearing
|
Depressive symptoms
|
|
Absent
|
Mild to moderate
|
Severe
|
|
n
|
%
|
n
|
%
|
n
|
%
|
Normal hearing thresholds
|
12
|
22,2
|
3
|
5,6
|
0
|
0
|
Mild hearing loss
|
8
|
14,8
|
8
|
14,8
|
1
|
1,9
|
Moderate hearing loss
|
9
|
16,7
|
12
|
22,2
|
1
|
1,9
|
Total
|
29
|
53,7
|
23
|
42,6
|
2
|
3,8
|
p = 0,18
Legend: n = absolute values, % = percentage values, p = significance level.
Discussion
Considering the increasing life expectancy and high prevalence of hearing loss in
the elderly population, it is important to check the interference of this change in
the psychosocial aspects.
With regard to depression, it was found that 25 elderly (46.3%) had depressive symptoms
of mild to profound. This value is higher than that described in the literature. Previous
work in the country, using the same instrument in this study (GDS) showed that approximately
30% of non-institutionalized elderly showed symptoms of depression[23]
[30]
[31]. It is noteworthy, however, that in these studies did not observe the auditory condition
of the sample components.
The data analysis showed that, in the study group, most of the elderly had hearing
loss (72.2%). This is higher than some studies reviewed[3]
[6] and less than others[4]. As described previously, the prevalence of presbycusis cited in the literature
varies widely (from 36% to 81%) believed that this variation may occur due to the
characteristics of the samples. It is noteworthy, however, that the study of Beria, Raymann, Giant, Figueiredo, Jotz, Roithmann \et al[4] evaluated a group of elderly in the South, as in this work, but with larger sample
size.Thus, it is believed that if there was an increase in the number of the sample,
the percentage of seniors with hearing loss would be equivalent, especially because
it is a similar population (elderly and the capital's metropolitan area of RS).
As to the degree it was found that hearing loss presented by the patients included
ranged from mild to moderate. This echoes the most data reported in the national literature[3]
[6]
[10] and international[9]. The mild hearing loss are not considered disabling by the World Health Organization[26]. One must consider, however, that studies on the acoustics of phonemes of Brazilian
Portuguese[32] show that sounds very important for speech discrimination, such as fricatives, exhibit
very low intensity (about 15dBNA). Thus, mild hearing loss should be considered important
and worthy of intervention, since they cause disturbances in speech understanding
and can contribute to the social isolation of the individual, causing or exacerbating
emotional and psychosocial disorders.
Analyzing the relationship between the presence / absence of depressive symptoms and
presence / absence of hearing loss, it was found that there was a significant association
(p = 0.016).The results showed that in the studied group, the presence of hearing
loss is contributing to the presence of psychological disorders. It is believed that
this fact can be partially explained by the removal of social and family relationships,
since the auditory disorders impede, partially or totally, the effective communication
between individuals and negatively affect social relations[11]
[12]
[13]
[14]
[15]
[16]
[17]
[18]
[33]
[34], both by the lack of understanding of the elderly, and the lack of silent environment
(most appropriate for auditory discrimination task) and even unprepared to make the
caller understand (speech more articulated and paused).
When comparing the results obtained in the degree of hearing loss / depression symptoms,
it was found, however, that there was no significant association (p = 0.18). Although
not significant (p = 0.18), the association between the degree of hearing loss was
positive in relation to the severity of the signs of depression. That is, the greater
the hearing loss, the greater the severity of the signs of depression. The data revealed,
then trend to this association, since the 29 elderly (53.7%) with absence of depression,
most had normal hearing (22.2%).Considering the 23 (42.6%) patients with mild to moderate
depression, only three (5.6%) had normal hearing. The others had mild hearing loss
(14.8%) or moderate (22.2% .) Individuals with severe depression (3.8%) had mild hearing
loss (1.9%) or moderate (1.9%).
Less consistent or weaker relationships between hearing loss and depression in the
elderly have been reported by other authors[35]
[36]. This fact can be attributed to psychological adaptation to hearing loss, which
varies from individual to individual, which occurs through a set of social and psychological
processes[37]
[38].
Another factor that should be taken into consideration is that depressive symptoms
may be related to difficulties in speech understanding experienced by the elderly,
but that such difficulties are not directly related to the changing level of hearing.
In a study by Magalhães \and Goffi-Gomez
[39], it was found that older adults with the same degrees of hearing loss had a different
index values of speech recognition probably due to the physiological substrate of
presbycusis (cochlear or retrocochlear alterations).
Conclusion
It is concluded that there was, in the elderly surveyed, a strong association between
hearing loss and signs of depression and tendency to be an association between the
degree of loss and severity of the signs of depression.