Prognostic assessment of patients with post-infectious olfactory dysfunction (PIOD) poses a challenge for clinicians. While there have been some studies on the prognostic factors of PIOD focusing on demographic factors, the aim of this study was to investigate whether event-related potentials (ERPs) could be used as a new predictor of olfactory recovery in PIOD.
This was a retrospective study involving patients who underwent olfactory examinations using Sniffin’ Sticks test before treatment and after 1 year of follow-up. The responder group was defined by an increase of threshold–discrimination–identification (TDI) score of ≥ 6 points. All patients underwent ERP examination and the amplitude and latency of each wave of ERPs were recorded before treatment.
A total of 61 patients (age 47.50 ± 11.04 years, 27 males) were analyzed. The presence of olfactory ERPs (oERPs) was greater in the responder group than in the non-responder group (P = 0.007), while that of trigeminal ERPs (tERPs) did not differ between the two groups (P = 0.346). Logistic-regression analyses showed that factors associated with improvement of subjective olfactory function were duration (OR, 1.604; 95% CI, 1.062–2.423; P = 0.025), initial threshold (odds ratio [OR], 0.043; 95% confidence interval [CI], 0.004–0.439; P = 0.008), and latency of N1 in oERPs (OR, 1.007; 95% CI, 1.001–1.013; P = 0.021).
Our study shows that duration of OD, initial threshold, and latency of N1 in oERPs were associated with olfactory improvement in PIOD patients, which may provide guidance for clinicians.
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There are no financial disclosures of the authors. This study was supported by the Natural Science Foundation of China (81670903), Capital Health Research and Development of Special Fund (2018-2-2065), Beijing Hospitals Authority’ Mission Plan (SML20190601), Beijing Scholars Program (No. 051), and Capital Health Research and Development of Special Fund (2018-2-2065).
Conflict of interest
All the authors declare that they have no conflict of interest.
This study was approved by the Ethics Committee of Beijing Anzhen Hospital, Capital Medical University, and had been performed in accordance with the ethical standards as laid down in the 1964 Helsinki Declaration and its later amendments or comparable ethical standards.
Informed consent was obtained from all individual participants included in the study.
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Guo, Y., Wu, D., Sun, Z. et al. Prognostic value of olfactory evoked potentials in patients with post-infectious olfactory dysfunction. Eur Arch Otorhinolaryngol 278, 3839–3846 (2021). https://doi.org/10.1007/s00405-021-06683-y
- Post-infectious olfactory dysfunction
- Olfactory training
- Sniffin’ Sticks test
- Event-related potentials