Intratympanic or systemic corticosteroids, which is more effective for treating sudden hearing loss?
USA: A recent Cochrane review states that for sudden hearing loss, there is no clarity on whether intratympanic treatment with corticosteroids is effective, or which of these treatments (intratympanic or systemic) is best. The review stated that intratympanic corticosteroids may have little or no effect compared with systemic corticosteroids for treating sudden hearing loss.
Sudden hearing loss is a condition characterized by the sudden onset (usually within 72 hours) of reduced or absent hearing. Corticosteroids, a type of anti-inflammatory medicine, are used for the treatment of the condition. These medicines are usually taken by mouth or injected into the body (known as systemic corticosteroids). However, it can also be given as a direct injection into the middle war via eardrum (known as intratympanic corticosteroids).
The study was conducted by SK Plontke and colleagues with the objective to assess the effects of intratympanic corticosteroids in people with idiopathic sudden sensorineural hearing loss (ISSNHL).
For this purpose, the researchers searched the online databases from their inception till 23 September 2021. Randomized controlled trials (RCTs) involving people with ISSNHL were included and followed up for over a week. Intratympanic corticosteroids were given as primary or secondary treatment (after the failure of systemic therapy).
To assess the evidence certainty, standard Cochrane methods, including GRADE were used. Change in hearing threshold with pure tone audiometry was the primary outcome. Secondary outcomes included the proportion of people whose hearing improved, final hearing threshold, speech audiometry, frequency-specific hearing changes, and adverse effects. A total of 30 studies that included 2133 people were included. The findings of the study are given below:
For people having their first treatment for sudden deafness
- The researchers did not find any studies that compared intratympanic corticosteroids to no treatment or placebo (dummy) treatment.
- Intratympanic corticosteroids might result in little or no difference in hearing when compared to people who receive systemic corticosteroids and might make little to no difference in the number of people whose hearing improves.
- The side effects may be different with these two types of treatment.
- With intratympanic treatment, people may have an increase in the risk of dizziness or ear pain as compared to systemic corticosteroids, typically at the time of injection, and some may develop a small hole in the eardrum. However, systemic treatment may also cause an increased risk of different side effects, such as problems with sugar levels in the blood.
- Taking intratympanic corticosteroids as well as systemic corticosteroids might result in a small improvement in hearing compared to systemic corticosteroids alone, but it is uncertain how many people would notice an improvement. As above, intratympanic treatment may cause some side effects, but we cannot be certain of the number of people who may experience these.
For people having additional treatment for sudden deafness (when their first treatment did not work)
- When compared to no treatment or a placebo (dummy) treatment, intratympanic corticosteroids may result in a much larger number of people having an improvement in their hearing but may only improve hearing slightly.
- As with the first treatment, intratympanic injections might cause some side effects, such as pain or dizziness at the time of the injection, or the development of a small hole in the eardrum. The authors are not certain how often these side effects will happen.
- There is uncertainty about whether adding intratympanic treatment to systemic treatment will result in an improvement in hearing.
To sum up, for primary therapy, intratympanic corticosteroids may have little or no effect compared with systemic corticosteroids. There may be a slight benefit from combined treatment when compared with systemic treatment alone, but the evidence is uncertain.
For secondary therapy, there is low-certainty evidence that intratympanic corticosteroids, when compared to no treatment or placebo, may result in a much higher proportion of participants whose hearing is improved, but may only have a small effect on the change in hearing threshold. Whether there is an additional benefit from combined treatment over systemic steroids alone is very uncertain.
"Although adverse effects were poorly reported, the different risk profiles of intratympanic treatment (including tympanic membrane perforation, pain and dizziness/vertigo) and systemic treatment (for example, blood glucose problems) should be considered when selecting appropriate treatment," the researchers conclude.
Reference:
Plontke SK, Meisner C, Agrawal S, Cayé-Thomasen P, Galbraith K, Mikulec AA, Parnes L, Premakumar Y, Reiber J, Schilder AGM, Liebau A. Intratympanic corticosteroids for sudden sensorineural hearing loss. Cochrane Database of Systematic Reviews 2022, Issue 7. Art. No.: CD008080. DOI: 10.1002/14651858.CD008080.pub2.
