Evaluation of the Auditory System in Adult Psoriasis Patients: A Prospective Cross-Sectional Study

INTRODUCTION

Psoriasis is a chronic, autoimmune, inflammatory skin condition, characterized clinically by well-defined erythematous indurated plaques predominantly on the extensor surfaces and scalp. It affects approximately 1%–3% of the global population.^1,2 The most common systemic association is psoriatic arthritis, present in >30% of the patients. However, psoriasis is also associated with metabolic syndrome, increased risk of coronary heart disease, dyslipidemia, alcoholism and smoking, psychological issues including anxiety and depression, etc.^3,4,5 A few studies have found involvement of the auditory system in psoriatic patients. In 1979, McCabe was the first to link sensorineural hearing loss (SNHL) to autoimmune illnesses, and he described it as “autoimmune sensorineural ear disease (ASED).”⁶ Some other studies have found a relationship between hearing loss and psoriasis.^7,8 However, at present there is a lack of literature demonstrating the association of the auditory disturbances in psoriasis patients. Therefore, we planned this study to evaluate the auditory system involvement in psoriasis and correlate the severity of auditory system involvement with the severity and duration of psoriasis.

MATERIAL AND METHODS

This observational, cross-sectional study was conducted from August 2020 to September 2021 using the STROBE checklist after obtaining clearance from the Institutional Ethical Committee (AIIMS/IEC/20/508). After written informed consent, patients aged 18 years or above who presented to the dermatology department were recruited. Patients with a history of pre-existing ear pathology, other spondyloarthropathies, autoimmune diseases, and pregnant and nursing mothers were excluded from the study. A total of 150 patients were enrolled. Personal and socioeconomic history, and clinical details of the patients were recorded. Psoriasis disease severity was determined by the psoriasis area and severity index (PASI) score and the affected body surface area (BSA). Evaluation of hearing was done by pure tone audiometry (PTA) in the otolaryngology department.

RESULTS

A total of 150 psoriasis patients were enrolled in the study. The majority were aged below 50 years (73.3%), with a male preponderance (males-70%, females-30%). The average age of disease onset was 32 years; the majority of the patients (79.3%) had a disease duration of <10 years. The scalp was the most common initial site of involvement (48%), followed by upper limbs (30%) and lower limbs (20%). The most common type of psoriasis was plaque psoriasis (85.3%), followed by scalp psoriasis (64%) and palmoplantar psoriasis (10%). Nearly one-third of the participants (38.26%) had a PASI score of >12, signifying severe psoriasis.

DISCUSSION

In our study, we performed PTA, which is the most basic and important hearing test used to determine hearing threshold levels. In our cohort, 83 out of 150 patients had hearing impairment in either one or both ears. Among these, SNHL was the most common type, followed by the mixed type and conductive hearing loss. Our study’s findings are consistent with those of previous studies. In their pilot study, Borgia et al. evaluated hearing function in 77 psoriasis patients and found SNHL was common in psoriasis patients.¹⁰ Güvenç et al. used PTA to evaluate the hearing function of 51 psoriasis patients and 51 healthy volunteers and found that the psoriasis patients’ threshold values were higher at all frequencies than the control subjects.⁸ In our study, most patients with hearing loss had grade 1 (mild) impairment in both ears, followed by moderate, severe, and profound impairment.

Of the 10 patients with psoriasis having psoriatic arthritis included in this study, 6 had SNHL. This is in agreement with the findings of the study by Srikumar et al., wherein bilateral sensorineural high-frequency hearing loss was the most common type.¹¹ In a study on psoriatic arthritis patients by Amor-Dorado et al., hearing impairment was found in 60% of patients with psoriatic arthritis. They hypothesized that these abnormalities could be caused by cochlear degeneration.¹²

We also found a significant correlation between the duration of psoriasis and hearing impairment. About 48% of the patients with a duration of illness ≤10 years had hearing impairment; however, in patients with a duration of illness >10 years, almost 80% of patients had hearing impairment. [Tables 4 and 5]. This is in concurrence with the findings of Borgia et al., wherein the severity of auditory involvement and psoriasis duration had a positive correlation. This can be attributed to prolonged inflammation leading to more severe and widespread manifestations.¹⁰

Another significant finding in our study was a statistically significant association between hearing loss and severity of psoriasis as defined by the BSA and PASI scores; that is, higher incidence and degree of hearing loss were found in patients with BSA > 10% and PASI > 12 (p-value < 0.05). Güvenç et al. also found a significant association between PASI score and hearing loss at medium and high frequencies.⁸ Similar findings were also noted by Borgia et al., wherein patients with severe psoriasis had a higher incidence and degree of hearing loss.¹⁰ The reason behind the positive correlation between high PASI scores and hearing impairment at medium-high frequencies could be high levels of proinflammatory cytokines like tumor necrosis factor-alpha, which is hypothesized to cause cochlear degeneration in the advanced stages of the disease. Hearing loss could also be because of the accumulation of leukocytes and local production of immunoglobulins, which can induce inflammatory reactions that lead to degeneration of the organ of Corti, stria vascularis, and spiral ganglion and inevitably cause SNHL.¹³ According to Berrocal et al., T lymphocyte-mediated cytotoxicity, concomitant vasculitis, and immune complex deposition with circulating proinflammatory cytokines were the most widely acknowledged causes of SNHL that accompanied immune-mediated diseases.¹⁴

In the current study, the majority of the psoriasis patients were found to have SNHL. Even though some studies have been performed on the association between psoriasis and hearing loss, the exact pathological mechanism is yet to be established. We believe that larger, community-based studies will shed additional light on this issue.

CONCLUSION

This study aimed to enhance our understanding of the association between psoriasis and auditory involvement. The current study demonstrates that a significant number of patients were found to have a sensorineural type of hearing loss. Psoriasis patients with severe disease activity and a duration of illness of more than 10 years were associated with a higher incidence and degree of hearing loss. The specific impact of psoriasis pathogenesis on the auditory system needs to be substantiated with well-designed experimental and prospective clinical studies. We recommend audiological screening and regular follow-up with audiometry in patients with long durations of illness and disease with moderate to severe psoriasis. This can aid in early diagnosis and prevent further deterioration in the hearing loss. Since hearing impairment can cause substantial discomfort and difficulty in daily life, such timely intervention may improve the patient’s quality of life.