Olfactory Training and Oral Corticosteroid Therapy for Persistent Postinfectious Hyposmia

Area of Science:

• Otolaryngology
• Neurology
• Pharmacology

Background:

• Persistent postinfectious hyposmia is a challenging condition, particularly in the postpandemic era.
• Current treatments, including corticosteroids, lack robust evidence for efficacy.
• Unproven therapies are frequently employed in clinical practice.

Purpose of the Study:

• To evaluate the effectiveness of systemic corticosteroid therapy combined with olfactory training for persistent postinfectious hyposmia.
• To compare outcomes between patients receiving olfactory training alone versus those receiving combined therapy.

Main Methods:

• A cohort of patients with persistent postinfectious hyposmia was divided into a control group (olfactory training only) and a test group (olfactory training plus a 7-day course of prednisone 40 mg).
• Olfactory function was assessed at baseline and at 3- and 6-month follow-ups using the visual analogue scale, Alcohol Sniff Test, and Connecticut Olfactory Test.
• Groups were compared for olfactory outcomes, with adjustments for comorbidities and age.

Main Results:

• No statistically significant difference in primary olfactory outcomes was observed between the test and control groups (p > 0.05).
• Both groups showed statistically significant improvement in Alcohol Sniff Test scores at 6 months (p > 0.05).
• A trend towards overall olfactory function improvement was noted, potentially due to spontaneous recovery or olfactory training, despite small sample size and lack of randomization.

Conclusions:

• Systemic corticosteroid therapy offers no statistically significant benefit for persistent postinfectious hyposmia.
• Olfactory training alone may contribute to olfactory function improvement.
• Treatment decisions regarding systemic corticosteroids for hyposmia should be individualized due to a lack of consensus and evidence.