Gustatory Dysfunction
The subjective GD, which was defined by impairment of the following four taste modalities: salty, sweet, bitter and sour,6 was reported in 53.7% (N=1,164), 15.3% (N=22) and 7.1% (N=19) of mild, moderate and severe-to-critical COVID-19 patients, respectively (Table 3). The prevalence of GD was significantly higher in mild patients compared with moderate and severe-to-critical patients (p=0.001). Aroma dysfunction (AD), which was defined as impairment of perception of tasting flavors in food and/or drinks that are not salty, sweet, bitter or sour (like chocolate, banana and fish), was evaluated in 2,105 patients. Among them, aroma perception was reduced in 1,116 patients (53.0%), loss in 330 subjects (15.7%) and distorted in 330 patients (15.7%). The overall prevalence of AD was 84.4%. AD concerned 80.7% of mild patients, while moderate and severe-to-critical COVID-19 patients had AD (distortion, reduction or loss) in 35.3% and 17.2% of cases, respectively (Table 3). The prevalence of AD was significantly higher in mild patients compared to moderate-to-critical (p=0.001).
The development of subjective GD was positively associated with the presence of diabetes (p=0.001). Diabetes was also associated with the development of AD (p=0.013). Patients with hypertension had a lower proportion of AD (47.0%) compared with those without hypertension (73.5%; p=0.003). Smokers reported more frequently AD (73.3%) compared with non-smoking COVID-19 patients (67.3%; p=0.002). Among patients with AD, non-smokers more frequently reported reduction of aroma perception compared with smokers who reported total loss or distortion of aroma perception.