Psychophysical Olfactory Tests and Detection of COVID-19 in Patients With Sudden Onset Olfactory Dysfunction: A Prospective Study

Objective: To investigate the coronavirus disease 2019 (COVID-19) status of patients with initial sudden olfactory anosmia (ISOA) through nasopharyngeal swabs for reverse transcription–polymerase chain reaction (RT-PCR) analysis and to explore their olfactory dysfunctions with psychophysical olfactory evaluation. Methods: A total of 78 ISOA patients were recruited from April 6, 2020, to April 10, 2020, through a public call of University of Mons (Mons, Belgium). Patients benefited from nasopharyngeal swabs and fulfilled the patient-reported outcome questionnaire. Among them, 46 patients performed psychophysical olfactory evaluation using olfactory identification testing. Based on the duration of the ISOA, 2 groups of patients were compared: patients with olfactory dysfunction duration ≤12 days (group 1) and those with duration >12 days (group 2). Results: In group 1, 42 patients (87.5%) had a positive viral load determined by RT-PCR and 6 patients (12.5%) were negative. In group 2, 7 patients (23%) had a positive viral load and 23 patients (77%) were negative. The psychophysical olfactory evaluation reported that anosmia and hyposmia occurred in 24 (52%) and 11 (24%) patients, respectively. Eleven patients were normosmic. The viral load was significantly higher in patients of group 1 compared with those of group 2. Conclusions: Coronavirus disease 2019 was detected in a high proportion of ISOA patients, especially over the first 12 days of olfactory dysfunction. Anosmia is an important symptom to consider in the detection of COVID-19 infection

Do olfactory and gustatory psychophysical scores have prognostic value in COVID-19 patients? A prospective study of 106 patients

Background: The lack of objective data makes it difficult to establish the prognostic value of chemosensitive disorders in coronavirus disease 2019 (COVID-19) patients. We aimed to prospectively monitor patients diagnosed with COVID-19 to see if the severity of olfactory and gustatory dysfunction associates with subsequent disease severity. Methods: Multicentre prospective study that recruited 106 COVID-19 subjects at diagnosis. Chemosensitive functions were assessed with psychophysical tests within 4 days of clinical onset, at 10 and 20 days. Daily body temperature and oxygen saturation were recorded as markers of disease severity alongside need for hospitalisation. The correlation between olfactory and gustatory scores and disease severity was assessed with linear regression analysis. Results: At T0, 71 patients (67%) presented with olfactory dysfunction while gustatory impairment was detected in 76 cases (65.6%). Chemosensitive disorders gradually improved over the observation period. No significant correlations were found between T0 chemosensitive scores and final disease severity. The correlation between olfactory scores and fever proved significant at T2 (p = 0.05), while the relationship with gustatory scores was significant at T1 (p = 0.01) and T2 (p < 0.001), however neither was clinically relevant. The correlation between chemosensitive scores and oxygen saturation was significant only for taste at T2 (p < 0.001). Logistic regression analysis found significant correlations between olfactory impairment severity and need for hospitalization at T2 (OR 3.750, p = 0.005). Conclusions: Initial objective olfactory and gustatory scores do not seem to have a significant prognostic value in predicting the severity of the COVID-19 course; however, persistence of olfactory dysfunction at 20 days, associated with a more severe course. Unfortunately, olfactory and gustatory dysfunction do not seem to hold prognostic value at the time of initial diagnosis

Olfactory function and viral recovery in COVID-19

Olfactory and taste disorders were reported in up to 30%-80% of COVID-19 patients. The purpose of our study was to objectively assess smell impairment in COVID-19 patients and to correlate olfactory function with viral recovery

Lawson criterion for ignition exceeded in an inertial fusion experiment

For more than half a century, researchers around the world have been engaged in attempts to achieve fusion ignition as a proof of principle of various fusion concepts. Following the Lawson criterion, an ignited plasma is one where the fusion heating power is high enough to overcome all the physical processes that cool the fusion plasma, creating a positive thermodynamic feedback loop with rapidly increasing temperature. In inertially confined fusion, ignition is a state where the fusion plasma can begin "burn propagation" into surrounding cold fuel, enabling the possibility of high energy gain. While "scientific breakeven" (i.e., unity target gain) has not yet been achieved (here target gain is 0.72, 1.37 MJ of fusion for 1.92 MJ of laser energy), this Letter reports the first controlled fusion experiment, using laser indirect drive, on the National Ignition Facility to produce capsule gain (here 5.8) and reach ignition by nine different formulations of the Lawson criterion

Prognostic indicators and outcomes of hospitalised COVID-19 patients with neurological disease: An individual patient data meta-analysis

BACKGROUND: Neurological COVID-19 disease has been reported widely, but published studies often lack information on neurological outcomes and prognostic risk factors. We aimed to describe the spectrum of neurological disease in hospitalised COVID-19 patients; characterise clinical outcomes; and investigate factors associated with a poor outcome. METHODS: We conducted an individual patient data (IPD) meta-analysis of hospitalised patients with neurological COVID-19 disease, using standard case definitions. We invited authors of studies from the first pandemic wave, plus clinicians in the Global COVID-Neuro Network with unpublished data, to contribute. We analysed features associated with poor outcome (moderate to severe disability or death, 3 to 6 on the modified Rankin Scale) using multivariable models. RESULTS: We included 83 studies (31 unpublished) providing IPD for 1979 patients with COVID-19 and acute new-onset neurological disease. Encephalopathy (978 [49%] patients) and cerebrovascular events (506 [26%]) were the most common diagnoses. Respiratory and systemic symptoms preceded neurological features in 93% of patients; one third developed neurological disease after hospital admission. A poor outcome was more common in patients with cerebrovascular events (76% [95% CI 67-82]), than encephalopathy (54% [42-65]). Intensive care use was high (38% [35-41]) overall, and also greater in the cerebrovascular patients. In the cerebrovascular, but not encephalopathic patients, risk factors for poor outcome included breathlessness on admission and elevated D-dimer. Overall, 30-day mortality was 30% [27-32]. The hazard of death was comparatively lower for patients in the WHO European region. INTERPRETATION: Neurological COVID-19 disease poses a considerable burden in terms of disease outcomes and use of hospital resources from prolonged intensive care and inpatient admission; preliminary data suggest these may differ according to WHO regions and country income levels. The different risk factors for encephalopathy and stroke suggest different disease mechanisms which may be amenable to intervention, especially in those who develop neurological symptoms after hospital admission

Prognostic indicators and outcomes of hospitalised COVID-19 patients with neurological disease: An individual patient data meta-analysis

Background Neurological COVID-19 disease has been reported widely, but published studies often lack information on neurological outcomes and prognostic risk factors. We aimed to describe the spectrum of neurological disease in hospitalised COVID-19 patients; characterise clinical outcomes; and investigate factors associated with a poor outcome. Methods We conducted an individual patient data (IPD) meta-analysis of hospitalised patients with neurological COVID-19 disease, using standard case definitions. We invited authors of studies from the first pandemic wave, plus clinicians in the Global COVID-Neuro Network with unpublished data, to contribute. We analysed features associated with poor outcome (moderate to severe disability or death, 3 to 6 on the modified Rankin Scale) using multivariable models. Results We included 83 studies (31 unpublished) providing IPD for 1979 patients with COVID-19 and acute new-onset neurological disease. Encephalopathy (978 [49%] patients) and cerebrovascular events (506 [26%]) were the most common diagnoses. Respiratory and systemic symptoms preceded neurological features in 93% of patients; one third developed neurological disease after hospital admission. A poor outcome was more common in patients with cerebrovascular events (76% [95% CI 67–82]), than encephalopathy (54% [42–65]). Intensive care use was high (38% [35–41]) overall, and also greater in the cerebrovascular patients. In the cerebrovascular, but not encephalopathic patients, risk factors for poor outcome included breathlessness on admission and elevated D-dimer. Overall, 30-day mortality was 30% [27–32]. The hazard of death was comparatively lower for patients in the WHO European region. Interpretation Neurological COVID-19 disease poses a considerable burden in terms of disease outcomes and use of hospital resources from prolonged intensive care and inpatient admission; preliminary data suggest these may differ according to WHO regions and country income levels. The different risk factors for encephalopathy and stroke suggest different disease mechanisms which may be amenable to intervention, especially in those who develop neurological symptoms after hospital admission