Prevalence of anosmia among COVID-19 patients in Taif City, Kingdom of Saudi Arabia

Abstract

Objectives: To assess the prevalence of anosmia in coronavirus-19 (COVID-19) patients. Coronavirus-19-related anosmia and hyposmia is a new emerging concept in the medical literature. Methods: A retrospective study on COVID-19 patients with anosmia and hyposmia was performed during the period between May-July, 2020. The inclusion criteria were all clinically stable COVID-19 patients >15 years old with positive reverse transcription-polymerase chain reaction (RT-PCR). Patients who refused to participate or leave incomplete questions were excluded. In this study, we investigated 1022 patients who met our criteria. Results: Olfactory dysfunction (OD) was reported by 53% of our COVID-19 patients, of which 32.7% were anosmic and 20.3% were hyposmic. Other neurological symptoms included ageusia (51.4%), fatigue (63%), myalgia (59.2%), and headache (50.9%), all of which showed significant association with OD. In addition, anosmia had a significant association with young age and female gender. However, there was no association between OD and pre-existing neurological disease. Conclusion: Half of our COVID-19 patients presented OD (anosmia/hyposmia), which often associated with ageusia and many neurological symptoms.

Relation between Vitamin B12 Levels and Smell Affection in COVID-19 Patients

“…Interestingly, the present study found that patients with smell affection were significantly younger than patients with normal smell, which is in line with the former study of Mubaraki et al 13 …”

“…Interestingly, the present study found that patients with smell affection were significantly younger than patients with normal smell, which is in line with the former study of Mubaraki et al 13 In this study, we assessed the relation between vitamin B12 levels and smell affection scores in COVID-19 patients. In the first and 4 weeks, groups with higher vitamin B12 levels had significantly better self-rated smell affection scores.…”

“…In comparison, one study from Saudi Arabia noted that olfactory dysfunction was reported by 53% of COVID-19 patients, of which 32.7% were anosmic and 20.3% were hyposmic. 13 In another study, anosmia was diagnosed in 44.0% of 500 COVID-19 patients from the United Arab Emirates, 14 while anosmia was reported in 67.0% of 288 Brazilian COVID-19 patients. 15 One large meta-analysis including data from 107 studies and 32,142 COVID-19 patients found that anosmia was reported in 12,038 patients with a prevalence of 38.2% (95% CI: 36.5%, 47.2%).…”

Prevalence, Patterns, Prognosis, and Psychosocial Impact of Olfactory and Gustative Dysfunctions Among Saudi COVID-19 Patients

“…There is great variability in the figures of OGD across the studies, reaching up to 74% [3][4][5][6][7][8]16]. Despite this discrepancy, both anosmia and ageusia were consistently defined as typical clinical features for COVID-19 infection and attracted much attention.…”

“…Among these atypical signs, olfactory and gustative dysfunctions (OGDs) were identified as hallmarks of SARS-COV-2 infection since the start of the pandemic and had a high diagnostic value, notably for paucisymptomatic cases [3]. Although described as common since the early series of cases, the prevalence of OGDs varied greatly, ranging between 6% up to 70% [3][4][5][6][7][8]. These symptoms are characterized by partial (hyposmia and hypogeusia) or total (anosmia and ageusia) loss of the senses of smell and taste, respectively, and were mainly reported in the acute phase of the disease, either isolated, preceding, or associated with other symptoms such as fever, dry cough, or headache [6,9,10].…”