Influence of vocal and aerodynamics aspects on the voice-related quality of life of older adults

Abstract The pursuit for quality of life urged a better understanding of aspects involved in ageing to minimize its consequences. Although many studies investigated older adults’ voice, aspects affecting this population voice-related quality of life have not yet been explored. Objective To investigate how aerodynamics and vocal aspects are associated with voice-related quality of life in older adults. Methodology fifty-six older adults aged 60 years or above – 39 women and 17 men – were evaluated. The following procedures were performed: application of the Voice-Related Quality of Life (V-RQOL) protocol; vocal assessment, including auditory-perceptual and acoustic analysis, from which we obtained fundamental frequency (F 0 ), standard deviation of fundamental frequency (SDF 0 ), shimmer, amplitude perturbation quotient (APQ), jitter, pitch period perturbation quotient (PPQ), and harmonics to noise ratio (HNR); aerodynamic assessment using a spirometer; and maximum phonation time (MPT) for /a/, /s/, /z/ and number counting. Results older adults tend to present high V-RQOL scores. Among women, roughness, APQ, and HNR parameters were negatively correlated with V-RQOL, whereas F 0 was positively. We found no correlation between spirometry measurements and V-RQOL. MPT for /a/, /z/, and number counting was positively correlated with V-RQOL solely among men. Conclusion Vocal roughness and acoustic parameters have a negative impact on the quality of life of older women. Respiratory aspects related to the available air support for speaking affected the most the voice-related quality of life of older men.


Introduction
The process of aging, in general, demonstrates a large individual variation in the organic and functional decline 1 that may affect the quality of life of the elderly, a better understanding of the issues involved in this process is necessary in order to minimize its consequences.
The quality of life depends on the interpretation and subjective perception that each individual makes of the facts and events relating to the events and conditions of their life. 2,3 It is therefore necessary to develop strategies for knowing how the elderly perceive their own aging.
Much like the quality of life, the impact of a specific health problem is difficult to measure. It is known that the degree of dysphonia is not directly proportional to the impact this exerts on the life of the dysphonic individual. 4  The aging of the voice occurs in a manner that is parallel to the other body functions. Throughout a person's life, the voice undergoes decay processes that depend on the way of life, 7 and a sequence of physiological events related to vocal fold aging. 8 In the elderly, decreased mobility of the laryngeal joints may occur due to ossification of cartilage, accompanied by atrophy of the vocal and laryngeal muscle, changes in the vocal fold cover and onset of glottal closure. [9][10][11][12] As for the vocal characteristics in the elderly, there is unstable voice, increase of the duration of articulatory pauses and speech rate reduction in voice; more breathy voice and of weak intensity, reduction of maximum phonation times. [13][14][15][16] Men and women may present anatomical differences in aging, such as edema in the female vocal folds, reducing the arch and incomplete glottal closure 9 and generate differences in vocal quality, as well as reduction in fundamental frequency in women 17 and an increase of such in men. 13 Vocal changes may be some of the factors that lead the elderly population to seek health services, noting, therefore, that the vocal conditions affect the overall quality of life of the elderly. Authors verified by acoustic analysis that there is deterioration of vocal quality in relation to aging and concluded that vocal therapy can improve the quality of life of elderly patients, leading to better vocal performance and social communicative interaction. 8 In addition to the laryngeal and vocal modifications, there are changes in the respiratory tract during the aging process negatively impacting aerodynamic measurements, 18 as insufficiency in respiratory support, reduction of the subglottic airway pressure with decreased vocal intensity and the maximum phonation time of the elderly. According to authors, changes in pulmonary function associated with glottic incompetence may have an intense impact on the vocal quality of this population. 19 It is also noteworthy that there is a difference in the vital capacity measures between elderly men and women, as well as the maximum phonatory time, and these measures are higher for males. 20 As in the larynx, the changes that occur in the respiratory system may hinder the oral Specifically in the elderly population, only one study correlated the auditory perceptual voice data with the quality of life in women, 14 revealing that even with high scores on quality of life protocols, the worse the voice quality, the greater impairment in the quality of life. In this sense, the hypothesis of this study is that changes resulting from vocal and/or respiratory aspects in elderly people interfere with their quality of life, and that this may occur similarly or differently in men and women. Know the interference these aspects in the quality of life of the elderly will to a broader understanding of the vocal problems and thus, speech therapy interventions in this population may be more effective.
The aim of this study was to investigate the correlation of vocal and aerodynamics of vocal function aspects with the quality of life in the voice of elderly men and women.

Voice-related quality of life
The elderly were instructed to fill out the protocol for the Voice-Related Quality Of Life (V-RQOL) 5 which assesses the impact of dysphonia on the quality of life.
The choice of this instrument is due to the fact that it is a rapid application, simple for the elderly to respond and effective for the objective that it pursues. When the elderly had difficulties to understand any word of the questions of the V-RQOL protocol, the evaluator explained the meaning of the word so that he could respond appropriately. The questionnaire has 10 items covering the physical functionality and socio-emotional domain. Their range of responses contains "it is not a problem", "it's a small problem," "it is a moderate / medium problem," "it is a big problem," "it is a very big problem." These responses are graded from 1 to 5, respectively. The calculation was performed according to the responses, the result of which can vary from 0 to 100 percent in which the results of higher value indicate a better quality of life. 5

Vocal evaluation
The vocal recordings were performed in an acoustically treated room where the elderly were instructed to perform the vowel /a/ in habitual pitch and loudness as well as a sample of spontaneous conversation. As for spontaneous speech, it was solicited the elderly answer the questions: "How was your day yesterday?" and "Tell me about your routine".

Spirometry
The Pony FX 12 (COSMED, Rome, Italy) liter spirometer was used for the spirometric evaluations.
A nozzle with its filter coupled to a spirometer and the plastic tube was placed in the vestibule of the mouth of the elderly, being asked to breathe normally until they got used to the system. The elderly remained comfortably seated in a chair and then the elderly

Statistical analysis
The correlation of all data assessed with the V-RQOL protocol was performed using the Spearman correlation. The significance level of 5% was adopted for all statistical analyzes.
The inter and intra judgement reliability was performed using the Intraclass correlation coefficient        (Table 4). The same was found in another study, 14 in which the parameters of the GRBASI scale correlated only with the physical domain and the total score of the V-RQOL protocol.
Regarding the acoustic parameters (Table 4) Limitations of this study can be attributed to limited participation of healthy elderly men. Also, because it is a non-specific protocol for this population, the scores of the protocol presented high, with possible masking other aspects that may influence the quality of life in voice of the elderly population.
Based on such, these results show us the direction to follow in speech therapy, since it shows the specific needs of the elderly, being different for each sex.

Conclusion
The vocal aspects of roughness and acoustic parameters had a negative impact on the quality of life among elderly women, which did not occur among the men. The aerodynamics of vocal function aspects related to air support available to speak negatively influenced the quality of life of elderly men.
Author's contributions