Long-term Consequences of COVID-19: Chemosensory Disorders.

PURPOSE OF REVIEW: A number of sequelae after acute coronavirus disease 2019 (COVID-19) significantly affect the quality of life of patients. The chemosensory disorders including olfactory dysfunction (OD) and gustatory dysfunction (GD) are two of the commonest symptoms complained by patients with COVID-19. Although chemosensory function has been reported improved in over 60% of COVID-19 patients in a short time after acute infection, it may last as a major symptom for patients with long COVID-19. This narrative review discussed current literatures on OD and GD in long COVID-19 including the prevalence, risk factors, possible mechanisms, and potential therapies. RECENT FINDINGS: Although the prevalence of OD and GD has declined continuously after acute COVID-19, a considerable number of patients had persistent chemosensory disorders 3 months to 2 years after symptom onset. Female gender, initial severity of dysfunction, nasal congestion, emotional distress and depression, and SARS-CoV-2 variants have been identified as risk factors for persistent OD and GD in long COVID-19. The pathogenesis of OD and GD in long COVID-19 remains unknown, but may be analogous to the persistent OD and GD post common respiratory viral infection. Corticosteroids and olfactory training might be a potential choice regarding the treatment of lasting OD and GD after SARS-CoV-2 infection; however, more studies are needed to prove it. OD and GD are common long-term consequences of COVID-19 and influenced by gender, initial severity of dysfunction, emotional distress and depression, and SARS-CoV-2 variants. More studies are needed to illustrate their pathogenesis and to establish therapeutic strategies.

Distinct effects of asthma and COPD comorbidity on disease expression and outcome in patients with COVID-19.

BACKGROUND: The impacts of chronic airway diseases on coronavirus disease 2019 (COVID-19) are far from understood. OBJECTIVE: To explore the influence of asthma and chronic obstructive pulmonary disease (COPD) comorbidity on disease expression and outcomes, and the potential underlying mechanisms in COVID-19 patients. METHODS: A total of 961 hospitalized COVID-19 patients with a definite clinical outcome (death or discharge) were retrospectively enrolled. Demographic and clinical information were extracted from the medical records. Lung tissue sections from patients suffering from lung cancer were used for immunohistochemistry study of angiotensin-converting enzyme II (ACE2) expression. BEAS-2B cell line was stimulated with various cytokines. RESULTS: In this cohort, 21 subjects (2.2%) had COPD and 22 (2.3%) had asthma. After adjusting for confounding factors, COPD patients had higher risk of developing severe illness (OR: 23.433; 95% CI 1.525-360.135; P < .01) and acute respiratory distress syndrome (OR: 19.762; 95% CI 1.461-267.369; P = .025) than asthmatics. COPD patients, particularly those with severe COVID-19, had lower counts of CD4+ T and CD8+ T cells and B cells and higher levels of TNF-α, IL-2 receptor, IL-10, IL-8, and IL-6 than asthmatics. COPD patients had increased, whereas asthmatics had decreased ACE2 protein expression in lower airways, compared with that in control subjects without asthma and COPD. IL-4 and IL-13 downregulated, but TNF-α, IL-12, and IL-17A upregulated ACE2 expression in BEAS-2B cells. CONCLUSION: Patients with asthma and COPD likely have different risk of severe COVID-19, which may be associated with different ACE2 expression.

Self-reported Taste and Smell Disorders in Patients with COVID-19: Distinct Features in China.

Last December 2019, a cluster of viral pneumonia cases identified as coronavirus disease 2019 (COVID-19) was reported in Wuhan, China. We aimed to explore the frequencies of nasal symptoms in patients with COVID-19, including loss of smell and taste, as well as their presentation as the first symptom of the disease and their association with the severity of COVID-19. In this retrospective study, 1206 laboratory-confirmed COVID-19 patients were included and followed up by telephone one month after discharged from Tongji Hospital, Wuhan. Demographic data, laboratory values, comorbidities, symptoms, and numerical rating scale scores (0-10) of nasal symptoms were extracted from the hospital medical records, and confirmed or reevaluated by the telephone follow-up. From patients (n=1172) completing follow-up, 199 (17%) subjects had severe COVID-19 and 342 (29.2%) reported nasal symptoms. 20.6% COVID-19 patients had loss of taste (median score=6), while 11.4% had loss of smell (median score=5). Loss of taste scores, but not loss of smell scores, were significantly increased in severe vs. non-severe COVID-19 patients. Interleukin (IL)-6 and lactose dehydrogenase (LDH) serum levels were positively correlated with loss of taste scores. About 80% of COVID-19 patients recovered from smell and taste dysfunction in 2 weeks. In this cohort, only 1 out of 10 hospital admitted patients had loss of smell while 1 out of 5 reported loss of taste which was associated to severity of COVID-19. Most patients recovered smell and taste dysfunctions in 2 weeks.