Olfactory and Gustatory Dysfunctions as a Clinical Manifestation of Coronavirus Disease 2019 in a Malaysian Tertiary Center

Abstract

Objective: To investigate the prevalence of olfactory and gustatory dysfunction among patients with COVID-19 infection and the recovery rate.

Methods: Adult patients (≥18 years) tested positive for COVID-19 via reverse transcription-polymerase chain reaction (RT-PCR) and admitted in Hospital Tuanku Ja'afar Seremban, Malaysia, were recruited in this study. Patients completed a questionnaire via telephone interview comprising the following details: age, sex, ethnicity, comorbidities, general and otorhinolaryngological symptoms, onset and duration of olfactory and gustatory dysfunction. Patients with persistent olfactory and gustatory dysfunction at the time of the initial interview were followed-up every 3 to 5 days till resolution.

Results: A total of 145 patients were included in our study. The mean age of patients was 43.0 ± 17.7 (range: 18-86). Fever (44.1%) and cough (39.3%) were the most prevalent general symptoms. Thirty-one patients (21.4%) reported olfactory dysfunction and 34 (23.4%) reported dysgeusia. There was a significant association between both olfactory and gustatory dysfunction (P < .001). Altered sense of smell or taste occurred before other symptoms in 7 (15.9%); concomitant in 16 (36.4%) and after in 15 (34.1%). Six patients (13.6%) reported isolated sudden-onset anosmia. The median duration of olfactory and gustatory dysfunctions was 7 days. Complete recovery was achieved for 70.5% of the patients within 7 days of symptom onset. Only 6 (19.4%) of the 31 patients with olfactory dysfunction experienced nasal obstruction or rhinorrhea. Olfactory dysfunction was not significantly associated with nasal obstruction or rhinorrhea. Olfactory dysfunction was significantly associated with younger age (P = .002), female (P = .011), and hyperlipidemia (P = .012). Gustatory dysfunction was significantly associated with fever (P = .019) and cough (P = .039).

Conclusion: Olfactory and gustatory dysfunction is a pertinent manifestation of COVID-19. Most of the affected patients achieve rapid and complete recovery. Sudden onset of olfactory and gustatory dysfunction should be recognized as a major symptom of COVID-19 as we implore to contain this pandemic.

Keywords: COVID-19; anosmia; coronavirus; dysgeusia; gustatory dysfunction; olfactory dysfunction.