DISCUSSION:
This study aimed to measure the rate of hoarseness among school-aged children. In our study, we found that the prevalence of hoarseness was 7.5%, which is within the same range reported in the literature as 6-23%.4 Dobres et al found in their study on the description of laryngeal pathologies in children with a sample size of 731 that the prevalence was more in males than in females, which was similar to the findings of Kallvik et al in their study on the prevalence of hoarseness in school-aged children with a sample size of 217.7,19 Children have a lower amount of elastin and their vocal fold is less stable than in adults who have a significant amount of elastin and collagen which provide more stability and provide the elastic propriety of the vocal folds. Consequently, the vocal fold of children with recurrent voice misuse vibrate more forcefully because of a lack of elastic proprieties, putting them at a higher risk of injury compared to adults,20 21 22hence that might account for the high rate of hoarseness in children.
In our study there was not a significant difference in the prevalence of hoarseness according to gender, though it was found to be higher in females than in males, which is similar to the prevalence in adults.3 It is suggested that the impact of gender on the voice is not significant in early childhood until the period when each gender acquires his or her specific voice tone and pattern as well as the social specific behavior of each gender.19,23,24
Concerning the possible risk factors of hoarseness, we found that a history of excessive crying during infancy was a possible factor associated with current hoarseness in our study. Kallvik et al reported a similar finding, whereby a history of heavy voice use during infancy was significantly associated with current voice quality, especially among females.19 Moreover, we found that a previous history of hoarseness was significantly associated with current hoarseness. Continued voice misuse in children and lack of education in voice therapy might keep them at high risk of repeated voice disorders. In our study, we found that letter articulation problems, or what is known as phonation disorder, was an associated risk factor of hoarseness in children. The exact reason is unknown but it might be due to the fact that a child with a problem in letter articulation will try hard to articulate the letters correctly, putting his voice in a repeated tension along with a misuse of his voice, eventually leading to voice disorders. Furthermore, letter articulation issues might be a symptom of hidden underlying structural abnormalities such as a cleft palate or neurological disorders.25 Additionally, in our study we found that stuttering was another possible risk factor for hoarseness. Stuttering or dysfluency is a type of speech disorder that prevents an individual from speaking fluently. As a result, a stutterer will repeat words, sounds, sentences, or take sudden involuntary breaks, which might lead to abnormal physical and emotional behaviors as the speaker struggles to end a particular sentence.26Stuttering can be developmental, which is the most common type, or acquired secondary to brain injury or emotional trauma.27,28 Salihović et al studied voice characteristics in stuttering children in their case-control experimental study and they found that the abnormal functioning of the larynx and high muscular tension as well as subglottic pressure with lack of coordination and control of respiratory muscles and laryngeal muscles all lead to voice disorders.29 Children who stutter were found to be at high risk of developing social anxiety, low self-esteem, and a decreased quality of life in the future.30,31 In our study, parents of children with hoarseness reported that their child’s educational outcome was affected by hoarseness; they also reported that their child felt inferior to other children and they were bothered by their voices. In this regard, early diagnosis of stuttering is important as it can have very promising outcomes with early interventions.32 Hence, early identification and referral to a speech language pathologist is required and suggested to parents.
The LPR is an inflammatory reaction caused by the backflow of gastric acid, which leads to laryngitis and pharyngitis.33 We found that those having symptoms suggesting LPR (RSI > 13) had a four-fold increased risk of hoarseness. Block et al found in their study on the role of LPR in children with hoarseness in a sample size of 337 participants that 47% of the children who presented with the main complaint of hoarseness were diagnosed with LPR and 68% of patients showed improvement in hoarseness after initiating anti-reflux management.18 Moreover, Gumpert et al found in their study that 90% of children with hoarseness had endoscopic signs of LPR.34 Carr et al described the endoscopic findings of LPR in their study as: lingual tonsillar hyperplasia, postglottic edema, and arytenoid edema.35 Remarkably, the study of Block et al found that 48% of patients diagnosed with LPR had no cough or throat clearing, which are the most common symptoms seen in children with LPR. Hence, hoarseness in children is an important key to diagnosing LPR.18 Most studies in the literature correlate the endoscopic finding of LPR with subjective complaints of hoarseness i.e. there is no acoustic voice analysis for hoarseness with an objective assessment. However, Niedzielska et al conducted a study on 11 participants in whom reflux disease was confirmed with pH-metric assessment in the esophagus as well as objective voice measurements with lupolaryngoscopy, stroboscopy, and acoustic voice analysis (jitter, shimmer, harmonic/noise ratio, and phonation time).36They confirmed the correlation between an inflammatory changed larynx and voice disorders.
To our knowledge, our study is the first large-scale study that has examined hoarseness in school-aged children in Saudi Arabia and investigated its related risk factors. However, our study had some limitations, including the subjective nature of the tools used (RSI and CVHI-10-P) and the lack of appropriate objective clinical and endoscopic evaluations of the larynx and head and neck region to confirm the diagnosis. Furthermore, one cannot solely depend on RSI for the diagnosis of LPR and more appropriate diagnostic tools such as an assessment of the patient’s pH levels are needed.37However, clinical assessment was offered to the children of interested parents for further evaluation of their child’s voice, but these findings were not included in the current study. Using a cross-sectional design limited the ability to identify the temporal sequences of events, thus causality of identified risk factors could not be established, especially considering the retrospective nature of the questionnaire and the possibility of recall bias and measurement error. However, due to the aim of covering a large sample of schools (n= 21) in the eastern province of the Kingdom, parents were contacted by their child’s class teacher via an online self-completed questionnaire that, unfortunately, resulted in a limited response rate from the parents, and consequently a possibility of selection bias. However, the resulting prevalence and risk estimations of associated factors of hoarseness in our study were comparable to those reported in the literature and therefore our results could be considered feasible.
In fact, the limited response rate might indicate the possibility of a low level of parental awareness regarding voice disorders in children and the need for further parental education to raise their awareness in the future.