Keywords bilateral hearing loss - neurosensory hearing loss - oncology - health impacts
Palavras-chave perda auditiva bilateral - perda auditiva neurossensorial - oncologia - impactos na
saúde
Introduction
The Pediatric Department of the Treatment and Research of A C Camargo Hospital, in
Sao Paulo, is the oldest in the country and for this reason, we can find patients
who were treated in 1953and, currently are off treatment. In order to evaluate the
possible sequelae and late effects that would interfere in the quality of life of
these subjects, we created a multidisciplinary group GEPETTO (Group of Pediatric Studies
about Late Effects of Oncological treatment) which evaluates the patients out of the
oncological treatment, in at least for 8 years. Some studies of this group were published
and described cardiac sequelae[1 ], frequency of sequelae by studied diseases[2 ] and the dentofacial sequelae[3 ].
One of the possible sequelae of oncologic treatment is the ototoxicity which leads
to a bilateral neurosensory hearing loss, damaging especially the high frequencies
and may also affect the low frequencies[4 ]
[5 ]
[6 ]
[7 ].
Hearing loss means losing an important way of contact with the world and with our
fellows. Although there are different levels of hearing losses, any blocking in the
sound conduction to the hearing nervous system means losing the contents of the message.
Such loss is greater in the children for being under development, it may interfere
in the language acquisition.
The hearing disorder induced by the use of ototoxics is most of the times underestimated.
Despite of presenting hearing loss, the patients only report complaint in determined
situations, such as in noisy environment, or refer losing or not comprehend only part
of the message, which leads the family for not believing the presence of hearing loss.
The loss of the acoustic information diminishes the probability to understand the
speech, as the impairment of the high frequencies turns difficult the consonants perception[8 ].
This associated to the treatment of global neoplasms can contribute to the isolation
of the patients with cancer[9 ].
The objective of this work is to investigate which are the audiometric frequencies
affected that are responsible for the hearing complaint in patients treated of cancer
in childhood.
Method
In the period of 2000 to 2004, it was evaluated 200 patients that had cancer in childhood,
treated between the periods of 1961-1996, and who was out of oncologic treatment,
at least for 08 years. From these 104 (52%) was of masculine gender and 96 (48%) of
feminine gender. The average age to the diagnosis was of 6,21 ± 4,71 years (average ± DP)
(variation: 0 - 18,6) and at the evaluation it was 21,7 ± 6,8 years (variation: 8
- 56). From these, 51 patients performed treatments that did not included radiotherapy
in the head and neck region neither chemotherapy using cisplatin (CDDP), 64 patients
were submitted to chemotherapy with CDDP and did not performed radiotherapy in the
region of head and neck, 75 patients were submitted to radiotherapeutic treatment
in head and neck region without chemotherapy regimen with cisplatin and 10 patients
were submitted to radiotherapy (Rxt) in head and neck region as well as chemotherapy
with cisplatin.
This study was approved and reviewed by the Ethics and Research Committee (CEP) protocol
number 549/03 of AC Camargo Hospital. The eligible patients or their responsible were
consulted about the possibility to participate signing a term of consent.
The patients were submitted to an anamnesis at ambulatory of Pediatrics as to investigate
the presence of hearing complaint and referred to hearing evaluation at Audiology
service, regardless of existence or not of hearing complaint. The questionnaire involved
hearing and otologic complaints and it was considered as presence of hearing complaint
the positive answer to the question: Do you think that you hear well, as well as more
than one question related to the hearing acuity and ringing. The meatoscopy was performed
before the examination and if the patient presented cerumen or any suspicion and/
or obstruction which would prevent the test performing, he was referred to otorhinolaryngologist
before evaluation.
The audiometric threshold tone was performed with Madsen Orbiter 922 audiometer and
TDH39 headset. The hearing lost was considered when the thresholds exceeded 20dB HL
in any frequency between 0,25 and 8kHZ (Schultz et al.)[10 ].
In order to check association between the variables hearing complaint and hearing
loss, it was used Fisher's exact test. For the entire statistical test, it was established
an error a = 5%, i.e., the results were considered statistically significant when
p < 0,05.
The patients were grouped according to the tone audiometric result and presence or
not of hearing complaint. It was divided in patients with normal hearing, hearing
loss in 8kHz, hearing loss 6-8kHz, hearing loss 4-8kHz, hearing loss 2-8kHz and hearing
loss ≤1-8kHz.
Results
The hearing loss was found in both ears. In whole group that was submitted to treatment
of risk for hearing, according the [Graphic 1 ] shows.
Graphic 1. Configuration of audiometric mean thresholds according to the type of treatment.
The hearing complaint was present in 44 patients (22%) of the sample being 34 patients
with complaint presented hearing loss. We observed a statistically significant relation
between the presence of hearing loss and hearing complaint ([Table 1 ]). From patients with complaint and without hearing loss, fours was of the group
without treatment risk, four was of the group with treatment with cisplatin, and two
were treated only with radiotherapy.
Table 1.
Distribution of the patients with or without hearing loss in relation of hearing complaint.
with compliant
without compliant
total
p
n (%)
n (%)
n (%)
With loss
34 (17%)
41 (21%)
75 (38%)
0.0001
Without loss
10 (5%)
115 (57%)
125 (62%)
Total
44 (22%)
125 (78%)
200 (100%)
The hearing losses were separated by audiometric frequency, in order to observe in
which frequency loss has significant statistically relation with complaint ([Table 2 ]).
Table 2.
Distribution of the patients according to the audiological evaluation result and presence
of hearing complaint.
Evaluation result audiological
with complaint
without complaint
total
Normal hearing
10
115
125
Hearing loss in 8kHz
1
15
16
Hearing loss in 6–8kHz
3
19
22
Hearing loss in 4–8kHz
10
6
16
Hearing loss in 2–8kHz
14
1
15
Hearing loss in ≤1–8kHz
6
0
6
Total
44
156
200
We could observe that the greater the number of frequencies affected by hearing loss,
the higher is the onset of hearing complaint showing a statistically significant relation
between hearing loss from of 4kHz and hearing complaint (p = 0.001) ([Tables 3 ] to [4 ]
[5 ]
[6 ]
[7 ]).
Table 3.
Statistics analysis of distribution of patients with hearing loss in 8kHz only and
without hearing loss related to the hearing complaint.
with compliant
without compliant
total
p
n (%)
n (%)
n (%)
With loss in 8kHz
1 (1%)
15 (11%) 1
6 (11%)
1.0
Without loss
10 (7%)
115 (82%)
125 (89%)
Total
11 (8%)
130 (92%)
141 (100%)
Table 4.
Statistics analysis of distribution of patients with hearing loss in 6–8kHz and without
hearing loss related to hearing complaint.
with compliant
without compliant
total
p
n (%)
n (%)
n (%)
With loss in 6k e 8kHz
3 (2%)
19 (13%)
22 (15%)
0.4
Without loss
10 (7%)
115 (78%)
125 (85%)
Total
13 (9%)
134 (91%)
147 (100%)
Table 5.
Statistics analysis of distribution of patients with hearing loss in only 4–8kHz and
without hearing loss related to hearing complaint.
with compliant
without compliant
total
p
n (%)
n (%)
n (%)
With loss between 4k e 8kHz
10 (7%)
6 (4%)
16(11%)
< 0.0001
Without loss
10 (7%)
115 (82%)
125 (89%)
Total
20 (14%)
121 (86%)
141 (100%)
Table 6.
Statistics analysis of distribution of patients with hearing loss in 2–8kHz and without
hearing loss related to hearing complaint.
with compliant
without compliant
total
p
n (%)
n (%)
n (%)
With loss between 2k e 8kHz
14 (10%)
1 (1%)
15 (11%)
< 0.0001
Without loss
10 (7%)
115 (82%)
125 (89%)
Total
24 (17%)
116 (83%)
141 (100%)
Table 7.
Statistics analysis of distribution of patients with hearing loss only in ≤1–8kHz
and without hearing loss related to the hearing complaint.
with compliant
without compliant
total
p
n (%)
n (%)
n (%)
With loss ≤ 1kHz–8kHz
6 (5%)
0 (0%)
6 (5%)
< 0.0001
Without loss
10 (8%)
116 (88%)
125 (89%)
Total
16 (12%)
115 (83%)
131 (100%)
Discussion
The hearing loss induced by the use of ototoxics has been studied, especially in oncologic
treatment[4 ]
[5 ]
[6 ]
[7 ]
[11 ]
[12 ]. Currently the increase in survival rates and with the increasing concern with quality
of life of the patients, it is important not only the hearing monitoring, but, especially
the hearing rehabilitation and comprehension of the real hearing necessities of each
individual. The loss characteristic is described as bilateral, descending and symmetrical[7 ]
[11 ] . In fact, the descending hearing implies difficulties of perception of the acute
phonemes in speech[8 ], placing these patients in risk to the communication difficulties, especially in
noisy environments.
Although we have found 10 patients (5%) with normal hearing with presence of complaint,
we remember that the ring was considered as complaint and also may be present in individuals
with normal hearing[13 ]
[14 ]. In fact, Teixeira et al.[15 ] also found in his population 50 elder individuals, 3 elders (6%) with normal hearing
with complaint.
In our study, we observe that the most of the patients with hearing loss also may
have hearing complaint, and that the greater the more frequencies are affected, the
greater is the occurrence of hearing complaint. Amorim et al.[16 ] found complaint in his study 30 musicians. The authors did not specified the hearing
involvement of individuals with complaint, however highlighted the most frequent complaint
in relation to buzz and the difficulty to comprehend in noisy environment.
In studies involving hearing complaint in the Portuguese speaking population, Calviti et al[17 ], Teixeira et al.[15 ] and Samelli et al.[18 ] studied the relation of hearing loss and hearing complaint, however did not studied
the relation of hearing loss with frequencies affected, but with the average of the
frequencies and the level of hearing loss. The risk to indentify by average, whether
encompassing 500 to 2kHz or 500 to 4kHz, or including 6kHz, is that in average we
lose some individual values which can make a difference. Calviti et al.[17 ] studied 71 elders, evaluating the relation between the perception of the handicap
and the audiometric averages. It was found presence of perception of handicap in 24
elders (58,5%) with hearing loss using tone average of 500 to 2kHz, and it was not
found significative variation when included in the average the frequencies of 4k and
6kHz. Teixeira et al.[15 ] found only 10 elders (20%) with hearing loss and with complaint, while 23 patients
(46%) with loss did not presented complaint. This relation can be justified by the
fact of hearing loss in elders, although bilateral and symmetrical, it is of insidious
onset, allowing the adaptation in your daily routine of lower hearing demand. In our
sample population is younger, with installation during childhood, with hearing demand
greater than the elders.
Currently, there are many ways to classify the hearing losses, however all of them
are based on average of tone thresholds of 500, 1000 and 2000Hz. This was not effective
in the cancer population[10 ], due to the hearing losses by ototoxicity began in the higher frequency and the
present study showed when it reached 4000Hz, it began to appear at hearing complaints.
In this way, only taking into account the losses in the frequencies of 500, 1000 e
2000, is not enough to identify the presence of loss with impact in the communication
or hearing complaint.
Samelli et al.[18 ] studied the possibility of using the raising complaints as method of triage in elderly.
They studied 185 elderly and answered the questionnaire raising complaints, which
was supplemented by audiological evaluation in 91 of them. Among the elders who performed
that audiological evaluation, they found 40 individual (44%) without hearing complaint
and with hearing complaint from mild to profound. Calviti et al.[17 ] found 17 elderly (24%) among of 71 studied with hearing loss and without complaint.
In our study, among the patients with loss, we found 41 (21%) who did not presented
complaint. From these, 34 patients (33%) had loss only in 8kHz or in 6k and 8kHz ([Table 2 ]). This fact has already been observed by our group, in the work of Liberman et al.[19 ] in which we highlighted minor losses can be asymptomatic. In other words, isolated
hearing loss in high frequency can be asymptomatic, reinforcing the importance of
audiological investigation in all other oncologic patients, regardless of hearing
complaints.
In our study, we observe that the presence of hearing complaints increased considerably
when the loss advanced to the frequencies which interfered directly in recognizing
the acute phonemes, such as the fricatives[8 ]
[20 ] It was possible to indentify the frequency of 4000Hz, as statistically significant
(p < 0.0001) for the onset of hearing complaint, which means that, from this frequency,
the impact and the hearing difficulty are imposed. It is noteworthy that although
it did not had practically had complaints in the young adult patients with hearing
loss in 6k and 8kHz, theses losses may have important consequences in the pediatric
population in development of speech and language.
This study is of utmost importance in oncologic patient when the frequency of 4kHz
is affected we can signal to the oncologist that the hearing loss at the moment will
have an important impact in the life of that patient and the oncologist could use
the information for the definition of conduct, mainly in the pediatric population.
Conclusion
The greater the number of the frequencies affected the greater id the occurrence of
hearing complaint, especially when the frequencies of speech are not involved, and
the involvement of 4 kHz already determines the appearance of complaints.
