A COMPARATIVE STUDY FOR PROGNOSIS OF ANOSMIA IN COVID19

Abstract

Background: Anosmia is common in Coronavirus disease 2019, but its impact on prognosis is
unknown. We aimed to analyze whether anosmia predicts in-hospital mortality or disease
severity; and if patients with anosmia have a different clinical presentation or inflammatory
response.
Methods: This retrospective observational case-control study included a total of 500 admitted
patients of COVID-19 at SMS Medical College and attached hospital, Jaipur.190 patients had
anosmia while 310 patients were without anosmia at the time of hospitalization. The patient’s
data concerning demography, clinical profile, underlying medical illness, severity of disease,
inflammatory markers, radiological imaging, and outcome were extracted from their medical
records. All collected data were tabulated, compiled, analyzed and compared among both
groups.
Results: Patients of both groups had matched demographic and underlying chronic medical
illness. Patients with anosmia had higher prevalence (35.79%) of mild disease as compared to
patients without anosmia (27.42%) with P = 0.0488. Similarly, proportion of severe disease
was significantly lower in patients with anosmia (9.47%) as compared to patients without
anosmia (27.42%) with P<0.01. COVID-19 related inflammatory markers especially
neutrophil-lymphocyte ratio (NLR), CRP, D-dimer, ferritin and IL-6 were found to be
significantly lower in patients with anosmia as compared to patients of without anosmia
(P<0.05).The average CTSS was found to be lower in patients with anosmia (10.54 ± 4.24) as
compared to patients without anosmia (15.61 ± 6.08) with P<0.01.Average duration of hospital
stay was found to be 10.18 days in patients with anosmia and it was 15.62 days in patients
without anosmia (P<0.01). Patients with anosmia had lesser mortality (0.53%) as compared to
the patients without anosmia which had higher mortality (3.23%) with P=0.0455.
Conclusion: The presence of anosmia was an independent predictor of good outcome as
reflected by a lower in-hospital mortality rate and lesser duration of hospital stay. In COVID19 patients with anosmia had early hospitalization, less severe form of disease, least raised  inflammatory markers, least lung involvement and least deterioration as compared to patients
without anosmia.