Hoarseness—Causes and Treatments

Dysphonia, with the cardinal symptom of hoarseness, has a prevalence of around 1% among patients in general (1) and a lifetime prevalence of approximately 30% (e1). The term dysphonia is used to describe any impairment of the voice—alteration in the sound of the voice with hoarseness, restriction of vocal performance, or strained vocalization. The pathophysiology of hoarseness is characterized by muscle tone– related irregularity in the oscillation of the vocal cords owing to hypertonic dysphonia, incomplete closure of the glottis on vocalization, or an increase in vocal cord bulk, perhaps due to a tumor (Figure 1a, ​,bb). Figure 1a Indirect laryngoscopy during phonation The aim of this review is to summarize the current knowledge of hoarseness: the potential causes, the means of diagnosis, the treatment options, and the evidence for their efficacy (eTable) (2, e2, e3). eTable Definition and classification of evidence levels and recommendation grades To this end, we carried out a selective survey of the literature using the search terms “hoarseness,” “hoarse voice,” and “dysphonia,” with particular reference to evidence-based guidelines from America (2, e4). Moreover, we included treatment recommendations from Cochrane reviews. Because no evidence-based guidelines have been published in German, we also took account of expert opinion. The causes of hoarseness are diverse: Acute and chronic laryngitis (accounting for 42.1% and 9.7% of cases respectively) Functional dysphonia (30%) Benign and malignant tumors (10.7 to 31.0% and 2.2 to 3.0% respectively) Neurogenic factors such as vocal cord paralysis (2.8 to 8%) Physiological aging (2%) Psychogenic factors (2.0 to 2.2%) (1, e5). Very occasionally hoarseness can be attributed to manifestations of laryngeal disease other than tumors (Table 1). Table 1 Causes and characteristics of hoarseness Suspicion of a serious underlying disease (Box, Figure 2) or persistence of hoarseness for more than 3 months (eTable) (2) should prompt immediate investigation by means of indirect laryngoscopy. Figure 1b Indirect laryngoscopy during respiration Box Serious comorbidities of hoarseness Comorbidities and additional risk factors that require urgent laryngoscopic examination by an otorhinolaryngologist: History of nicotine and/or alcohol consumption Enlarged cervical lymph nodes Hoarseness following trauma Association with hemoptysis, dysphagia, odynophagia, otalgia, or dyspnea Neurological symptoms Unexplained weight loss Progression of hoarseness Immunosuppression Possible bolus aspiration Hoarseness after an operative intervention (intubation, neck surgery)