Epidemiological Study of Unilateral Sensorineural Hearing Loss in Adults

Abstract

Introduction: Unaddressed hearing loss poses great loss with an annual risk of 750 billion United States dollars. In India, the incidence of adult-onset deafness is found to be around 7.6%. Unilateral Sensorineural Hearing Loss (USNHL) has been found to affect 7.9%–13.3% of the Indian population. Since, most of the literature available is on bilateral Sensorineural Hearing Loss (SNHL), and limited work is done on USNHL. Hence, this study tends to list and analyze the clinical characteristics of patients with USNHL and is the largest Indian series related to clinical profile of USNHL. Materials and Methods: A prospective observational study was conducted in the Department of Otorhinolaryngology to study the clinico-epidemiological profile of 130 adult patients having USNHL. Patients were worked up using clinical, audiological, laboratory, and radiological tests, to reach a particular diagnosis. Results: The most common age group seen was 36–45 years (36.9%) with male preponderance. The majority of patients had an education of less than high school. About 27.7% of the patients had associated tinnitus and vertigo both. Most of the patients (30%) presented with 1–5-years duration of illness and noise as the most common associated risk factor. Forty-three percent of patients had profound hearing loss. Magnetic resonance imaging (MRI) was done in 37% of patients and was found to be diagnostic in 6.1% of cases. The most common etiology found was idiopathic progressive SNHL (43.1%). Conclusion: USNHL was more commonly seen in nonelderly males. Majority had profound hearing loss and presented very late. This study also mentions the possible socioeconomic correlate of the patients with their clinical profile. MRI is useful in detecting rare etiologies such as dolichoectasia, multiple sclerosis, schwannoma, and vestibulocochlear anomalies. A very diverse etiology of USNHL was seen.