Natural trajectory of recovery of COVID-19 associated olfactory loss.

IMPORTANCE: Prevalence of post-viral olfactory loss has increased dramatically due to the frequency and severity of olfactory dysfunction associated with infection by the SARS-CoV-2 virus. OBJECTIVE: To determine the trajectory of COVID-19 olfactory loss over a six-month period. A key secondary objective is to assess predictive factors associated with the recovery of olfaction. DESIGN: Longitudinal repeated-measures study that enrolled from May 5, 2020 to February 2, 2021, with the last date of data collection on June 15, 2021. SETTING: Barnes-Jewish HealthCare/Washington University School of Medicine facilities (Saint Louis, Missouri, USA). PARTICIPANTS: Individuals who tested positive for SARS-CoV-2 by real-time polymerase chain reaction on nasopharyngeal swab and indicated olfactory loss on COVID-19 screening questionnaire. Individuals were excluded if they had previously diagnosed history of olfactory loss, neurodegenerative disorders, <18 years of age, admitted to hospital service, unable to read, write, and understand English, or lacked computer or internet access. INTERVENTIONS/EXPOSURES: Watch and wait for spontaneous recovery. MAIN OUTCOME(S) AND MEASURE(S): Participants completed olfactory assessments every 30 days for six months. Each assessment consisted of the University of Pennsylvania Smell Identification Test (UPSIT), an objective "scratch-and-sniff" test, and Clinical Global Impressions (CGI), a subjective Likert rating scale. RESULTS: The mean age was 41 years old (SD = 16). 39 (80 %) were female and 42 (86 %) white. At baseline assessment of objective olfaction, 18 (36 %) participants had anosmia or severe hyposmia. Subjective, complete recovery at six months was 81 % (95 % CI 74 % to 88 %). Likelihood of recovery was associated with age <50 years (aHR = 8.1 (95 % CI 1.1 to 64.1)) and mild olfactory loss at baseline (UPSIT = 30-33 for males and 31-34 for females) (aHR 6.2 (95 % CI 1.2 to 33.0)). CONCLUSIONS AND RELEVANCE: The trajectory of olfactory recovery among adults with COVID-19 olfactory loss illustrated rapid recovery within 2-3 weeks of infection, and by six months 81 % had recovered based on self-report. Age <50 years old and mild severity of olfactory loss at baseline were associated with increased likelihood of recovery of olfaction. These findings can be used to inform shared decision-making with patients.

Relationship Between Preexisting Cardiovascular Disease and Death and Cardiovascular Outcomes in Critically Ill Patients With COVID-19.

BACKGROUND: Preexisting cardiovascular disease (CVD) is perceived as a risk factor for poor outcomes in patients with COVID-19. We sought to determine whether CVD is associated with in-hospital death and cardiovascular events in critically ill patients with COVID-19. METHODS: This study used data from a multicenter cohort of adults with laboratory-confirmed COVID-19 admitted to intensive care units at 68 centers across the United States from March 1 to July 1, 2020. The primary exposure was CVD, defined as preexisting coronary artery disease, congestive heart failure, or atrial fibrillation/flutter. Myocardial injury on intensive care unit admission defined as a troponin I or T level above the 99th percentile upper reference limit of normal was a secondary exposure. The primary outcome was 28-day in-hospital mortality. Secondary outcomes included cardiovascular events (cardiac arrest, new-onset arrhythmias, new-onset heart failure, myocarditis, pericarditis, or stroke) within 14 days. RESULTS: Among 5133 patients (3231 male [62.9%]; mean age 61 years [SD, 15]), 1174 (22.9%) had preexisting CVD. A total of 1178 (34.6%) died, and 920 (17.9%) had a cardiovascular event. After adjusting for age, sex, race, body mass index, history of smoking, and comorbidities, preexisting CVD was associated with a 1.15 (95% CI, 0.98-1.34) higher odds of death. No independent association was observed between preexisting CVD and cardiovascular events. Myocardial injury on intensive care unit admission was associated with higher odds of death (adjusted odds ratio, 1.93 [95% CI, 1.61-2.31]) and cardiovascular events (adjusted odds ratio, 1.82 [95% CI, 1.47-2.24]), regardless of the presence of CVD. CONCLUSIONS: CVD risk factors, rather than CVD itself, were the major contributors to outcomes in critically ill patients with COVID-19. The occurrence of myocardial injury, regardless of CVD, and its association with outcomes suggests it is likely due to multiorgan injury related to acute inflammation rather than exacerbation of preexisting CVD. REGISTRATION: NCT04343898; https://clinicaltrials.gov/ct2/show/NCT04343898.

Development and Psychometric Validation of the Olfactory Dysfunction Outcomes Rating.

Importance: Olfactory dysfunction (OD) is an increasingly common and morbid condition, especially given the ongoing COVID-19 pandemic. Thus, the ability to reproducibly measure smell loss-associated quality of life (QOL) and its response to treatment is paramount. Objective: To develop and validate a concise and visually appealing smell loss-associated QOL patient-reported outcome measure for OD. Design, Setting, and Participants: A secondary analysis of comments to an online survey by 1000 patients with olfactory dysfunction published in 2013 was used as the primary source to generate items of the Olfactory Dysfunction Outcomes Rating (ODOR). In addition, 30 patients with OD enrolled in 2 clinical studies at a tertiary care medical center (Washington University) were asked to identify their main concerns associated with smell loss. And finally, 4 otolaryngologists reviewed the items generated from the online survey and the patients' interviews to identify any additional items. Prospective study design was used for data collection from the 30 patients and 4 otolaryngologists. Prospective study design was used for survey validation. Validation of the ODOR was performed with 283 patients enrolled in several prospective studies at a single institution that completed the ODOR as an outcome measure. Main Outcomes and Measures: Item generation and selection were the outcomes of ODOR development. The psychometric and clinimetric measures evaluated for validation were internal consistency, test-retest reliability, face and content validity, concurrent validity, and discriminant validity. Minimal clinically important difference was also determined. Results: The ODOR is a 28-item instrument with each item scored as either no difficulty or very rarely bothered (0) to complete difficulty or very frequently bothered (4) with a total instrument score range of 0 to 112 points. Higher scores indicate higher degree of dysfunction and limitation. Validation in the cohort of 283 patients (mean [SD] age, 47.0 [14.4] years; 198 female participants [73%]; 179 White participants [80%]) revealed that the instrument has high internal consistency (Cronbach α = 0.968), test-retest reliability (r = 0.90 [95% CI, 0.81-0.95]), face validity, content validity, concurrent validity (r = 0.87 [95% CI, 0.80-0.91] compared with the Questionnaire of Olfactory Disorders-Negative Statements; ρ = -0.76 [95% CI, -0.81 to -0.71] compared with a patient-reported symptom severity scale), and divergent validity (mean score difference, -33.9 [95% CI, -38.3 to -29.6] between normosmic patients and hyposmic/anosmic patients). The minimal clinically important difference was 15 points. The estimated time for survey completion was approximately 5 minutes. Conclusions and Relevance: In this survey creation and validation study, the ODOR was shown to be a novel, concise, reliable, and valid patient-reported outcome measure of OD-associated QOL. It can be used to measure physical problems, functional limitations, and emotional consequences associated with OD and how they change after a given intervention, which is clinically applicable and particularly pertinent given the growing burden of OD associated with COVID-19.

Modulation of the Association Between Age and Death by Risk Factor Burden in Critically Ill Patients With COVID-19.

Older age is a key risk factor for adverse outcomes in critically ill patients with COVID-19. However, few studies have investigated whether preexisting comorbidities and acute physiologic ICU factors modify the association between age and death. DESIGN: Multicenter cohort study. SETTING: ICUs at 68 hospitals across the United States. PATIENTS: A total of 5,037 critically ill adults with COVID-19 admitted to ICUs between March 1, 2020, and July 1, 2020. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The primary exposure was age, modeled as a continuous variable. The primary outcome was 28-day inhospital mortality. Multivariable logistic regression tested the association between age and death. Effect modification by the number of risk factors was assessed through a multiplicative interaction term in the logistic regression model. Among the 5,037 patients included (mean age, 60.9 yr [± 14.7], 3,179 [63.1%] male), 1,786 (35.4%) died within 28 days. Age had a nonlinear association with 28-day mortality (p for nonlinearity <0.001) after adjustment for covariates that included demographics, preexisting comorbidities, acute physiologic ICU factors, number of ICU beds, and treatments for COVID-19. The number of preexisting comorbidities and acute physiologic ICU factors modified the association between age and 28-day mortality (p for interaction <0.001), but this effect modification was modest as age still had an exponential relationship with death in subgroups stratified by the number of risk factors. CONCLUSIONS: In a large population of critically ill patients with COVID-19, age had an independent exponential association with death. The number of preexisting comorbidities and acute physiologic ICU factors modified the association between age and death, but age still had an exponential association with death in subgroups according to the number of risk factors present. Additional studies are needed to identify the mechanisms underpinning why older age confers an increased risk of death in critically ill patients with COVID-19.

Hispanic ethnicity and mortality among critically ill patients with COVID-19.

BACKGROUND: Hispanic persons living in the United States (U.S.) are at higher risk of infection and death from coronavirus disease 2019 (COVID-19) compared with non-Hispanic persons. Whether this disparity exists among critically ill patients with COVID-19 is unknown. OBJECTIVE: To evaluate ethnic disparities in mortality among critically ill adults with COVID-19 enrolled in the Study of the Treatment and Outcomes in Critically Ill Patients with COVID-19 (STOP-COVID). METHODS: Multicenter cohort study of adults with laboratory-confirmed COVID-19 admitted to intensive care units (ICU) at 67 U.S. hospitals from March 4 to May 9, 2020. Multilevel logistic regression was used to evaluate 28-day mortality across racial/ethnic groups. RESULTS: A total of 2153 patients were included (994 [46.2%] Hispanic and 1159 [53.8%] non-Hispanic White). The median (IQR) age was 62 (51-71) years (non-Hispanic White, 66 [57-74] years; Hispanic, 56 [46-67] years), and 1462 (67.9%) were men. Compared with non-Hispanic White patients, Hispanic patients were younger; were less likely to have hypertension, chronic obstructive pulmonary disease, coronary artery disease, or heart failure; and had longer duration of symptoms prior to ICU admission. During median (IQR) follow-up of 14 (7-24) days, 785 patients (36.5%) died. In analyses adjusted for age, sex, clinical characteristics, and hospital size, Hispanic patients had higher odds of death compared with non-Hispanic White patients (OR, 1.44; 95% CI, 1.12-1.84). CONCLUSIONS: Among critically ill adults with COVID-19, Hispanic patients were more likely to die than non-Hispanic White patients, even though they were younger and had lower comorbidity burden. This finding highlights the need to provide earlier access to care to Hispanic individuals with COVID-19, especially given our finding of longer duration of symptoms prior to ICU admission among Hispanic patients. In addition, there is a critical need to address ongoing disparities in post hospital discharge care for patients with COVID-19.

Efficacy and Safety of Saline Nasal Irrigation Plus Theophylline for Treatment of COVID-19-Related Olfactory Dysfunction: The SCENT2 Phase 2 Randomized Clinical Trial.

Importance: Recent studies suggest that theophylline added to saline nasal irrigation (SNI) can be an effective treatment for postviral olfactory dysfunction (OD), a growing public health concern during the COVID-19 pandemic. Objective: To evaluate the efficacy and safety of theophylline added to SNI compared with placebo for COVID-19-related OD. Design, Setting, and Participants: This triple-blinded, placebo-controlled, phase 2 randomized clinical trial was conducted virtually between March 15 and August 31, 2021. Adults residing in Missouri or Illinois were recruited during this time period if they had OD persisting for 3 to 12 months following suspected COVID-19 infection. Data analysis was conducted from October to December 2021. Interventions: Saline sinus rinse kits and bottles of identical-appearing capsules with either 400 mg of theophylline (treatment) or 500 mg of lactose powder (control) were mailed to consenting study participants. Participants were instructed to dissolve the capsule contents into the saline rinse and use the solution to irrigate their nasal cavities in the morning and at night for 6 weeks. Main Outcomes and Measures: The primary outcome was the difference in the rate of responders between the treatment and the control arms, defined as a response of at least slightly better improvement in the Clinical Global Impression-Improvement scale posttreatment. Secondary outcome measures included changes in the University of Pennsylvania Smell Identification Test (UPSIT), the Questionnaire for Olfactory Disorders, the 36-Item Short Form Health Survey on general health, and COVID-19-related questions. Results: A total of 51 participants were enrolled in the study; the mean (SD) age was 46.0 (13.1) years, and 36 (71%) participants were women. Participants were randomized to SNI with theophylline (n = 26) or to SNI with placebo (n = 25). Forty-five participants completed the study. At the end of treatment, 13 (59%) participants in the theophylline arm reported at least slight improvement in the Clinical Global Impression-Improvement scale (responders) compared with 10 (43%) in the placebo arm (absolute difference, 15.6%; 95% CI, -13.2% to 44.5%). The median difference for the UPSIT change between baseline and 6 weeks was 3.0 (95% CI, -1.0 to 7.0) for participants in the theophylline arm and 0.0 (95% CI, -2.0 to 6.0) for participants in the placebo arm. Mixed-model analysis revealed that the change in UPSIT scores through study assessments was not statistically significantly different between the 2 study arms. Eleven (50%) participants in the theophylline arm and 6 (26%) in the placebo arm had a change of 4 or more points in UPSIT scores from baseline to 6 weeks. The difference in the rate of responders as measured by the UPSIT was 24% (95% CI, -4% to 52%) in favor of theophylline. Conclusions and Relevance: This randomized clinical trial suggests that the clinical benefit of theophylline nasal irrigations on olfaction in participants with COVID-19-related OD is inconclusive, though suggested by subjective assessments. Larger studies are warranted to investigate the efficacy of this treatment more fully. Trial Registration: ClinicalTrials.gov Identifier: NCT04789499.

At-Home Screening Tool for Anosmia

IMPACT: By developing and validating a simple and cost-effective at-home screening tool for loss of smell, we can efficiently detect infection with COVID-19, neuropsychiatric disease such as Alzheimer’s, and post-operative smell loss. OBJECTIVES/GOALS: To develop and validate a feasible and cost-effective screening tool for olfactory dysfunction (OD) using common household items. METHODS/STUDY POPULATION: The study has two phases. In the Development phase, 120 participants with self-reported smell changes will complete a survey with a list of 45 household items to smell. Item reduction to develop the NASAL Short Smell Test will occur by measuring content validity, factor analysis, and internal consistency. In the Validation phase, 200 participants with self-reported smell changes will take the NASAL Short Smell Test at baseline and again at three weeks. In both phases, the validated University of Pennsylvania Smell Identification Test (UPSIT) will be used as the gold standard. Measures of performance as well as test-retest reliability and sensitivity to change will be measured. RESULTS/ANTICIPATED RESULTS: We anticipate that the majority of participants will have at least half of the items in their household and will report ability to smell for each. Measures of sensitivity, specificity, likelihood ratios, and UPSIT score correlations will allow us to evaluate performance of each item. Item reduction will allow us to create the NASAL Short Smell Test, in which a handful of common items will be used to create a screening tool for smell loss. The Validation phase will allow us to measure discriminative performance of this tool as well as test-retest reliability and sensitivity to change, which we expect to be at least comparable to the validated UPSIT. DISCUSSION/SIGNIFICANCE OF FINDINGS: Current tools for diagnosis of OD are costly, time-consuming, and often require a clinician to evaluate. The validation of the simple at-home NASAL Short Smell Test to screen for OD will allow us to detect infection with COVID-19, neuropsychiatric disease, or post-operative smell loss quickly and efficiently.

Development and Validation of a Novel At-home Smell Assessment.

IMPORTANCE: Current tools for diagnosis of olfactory dysfunction (OD) are costly, time-consuming, and often require clinician administration. OBJECTIVE: To develop and validate a simple screening assessment for OD using common household items. DESIGN, SETTING, AND PARTICIPANTS: This fully virtual diagnostic study included adults with self-reported OD from any cause throughout the US. Data were collected from December 2020 to April 2021 and analyzed from May 2021 to July 2021. MAIN OUTCOMES AND MEASURES: Participants with self-reported olfactory dysfunction took a survey assessing smell perception of 45 household items and completed the Clinical Global Impression-Severity (CGI-S) smell questionnaire, the University of Pennsylvania Smell Identification Test (UPSIT), and the 36-item Short Form Survey (SF-36). Psychometric and clinimetric analyses were used to consolidate 45 household items into 2 short Novel Anosmia Screening at Leisure (NASAL) assessments, NASAL-7 (range, 0-14; lower score indicating greater anosmia) and NASAL-3 (range, 0-6; lower score indicating greater anosmia). RESULTS: A total of 115 participants were included in the study, with a median (range) age of 42 (19-70) years, 92 (80%) women, and 97 (84%) White individuals. There was a moderate correlation between the UPSIT and NASAL-7 scores and NASAL-3 scores (NASAL-7: ρ = 0.484; NASAL-3: ρ = 0.404). Both NASAL-7 and NASAL-3 had moderate accuracy in identifying participants with anosmia as defined by UPSIT (NASAL-7 area under the receiver operating curve [AUC], 0.706; 95% CI, 0.551-0.862; NASAL-3 AUC, 0.658; 95% CI, 0.503-0.814). Scoring 7 or less on the NASAL-7 had 70% (95% CI, 48%-86%) sensitivity and 53% (95% CI, 43%-63%) specificity in discriminating participants with anosmia from participants without. Scoring 2 or less on the NASAL-3 had 57% (95% CI, 36%-76%) sensitivity and 78% (95% CI, 69%-85%) specificity in discriminating participants with anosmia from participants without. There was moderate agreement between UPSIT-defined OD categories and those defined by NASAL-7 (weighted κ = 0.496; 95% CI, 0.343-0.649) and those defined by NASAL-3 (weighted κ = 0.365; 95% CI, 0.187-0.543). The agreement with self-reported severity of olfactory dysfunction as measured by CGI-S and the NASAL-7 and NASAL-3 was moderate, with a weighted κ of 0.590 (95% CI, 0.474-0.707) for the NASAL-7 and 0.597 (95% CI, 0.481-0.712) for the NASAL-3. CONCLUSION AND RELEVANCE: The findings of this diagnostic study suggest that NASAL-7 and NASAL-3, inexpensive and brief patient-reported assessments, can be used to identify individuals with OD. As the burden of COVID-19-associated OD increases, these assessments may prove beneficial as screening and diagnostic tools. Future work will explore whether the NASAL assessments are sensitive to change and how much of a change is clinically important.

Sex-related differences in mortality, acute kidney injury, and respiratory failure among critically ill patients with COVID-19.

ABSTRACT: Although the number of deaths due to coronavirus disease 2019 (COVID-19) is higher in men than women, prior studies have provided limited sex-stratified clinical data.We evaluated sex-related differences in clinical outcomes among critically ill adults with COVID-19.Multicenter cohort study of adults with laboratory-confirmed COVID-19 admitted to intensive care units at 67 U.S. hospitals from March 4 to May 9, 2020. Multilevel logistic regression was used to evaluate 28-day in-hospital mortality, severe acute kidney injury (AKI requiring kidney replacement therapy), and respiratory failure occurring within 14 days of intensive care unit admission.A total of 4407 patients were included (median age, 62 years; 2793 [63.4%] men; 1159 [26.3%] non-Hispanic White; 1220 [27.7%] non-Hispanic Black; 994 [22.6%] Hispanic). Compared with women, men were younger (median age, 61 vs 64 years, less likely to be non-Hispanic Black (684 [24.5%] vs 536 [33.2%]), and more likely to smoke (877 [31.4%] vs 422 [26.2%]). During median follow-up of 14 days, 1072 men (38.4%) and 553 women (34.3%) died. Severe AKI occurred in 590 men (21.8%), and 239 women (15.5%), while respiratory failure occurred in 2255 men (80.7%) and 1234 women (76.5%). After adjusting for age, race/ethnicity and clinical variables, compared with women, men had a higher risk of death (OR, 1.50, 95% CI, 1.26-1.77), severe AKI (OR, 1.92; 95% CI 1.57-2.36), and respiratory failure (OR, 1.42; 95% CI, 1.11-1.80).In this multicenter cohort of critically ill adults with COVID-19, men were more likely to have adverse outcomes compared with women.

Association of Surge Conditions with Mortality Among Critically Ill Patients with COVID-19.

OBJECTIVE: To determine whether surge conditions were associated with increased mortality. DESIGN: Multicenter cohort study. SETTING: U.S. ICUs participating in STOP-COVID. PATIENTS: Consecutive adults with COVID-19 admitted to participating ICUs between March 4 and July 1, 2020. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The main outcome was 28-day in-hospital mortality. To assess the association between admission to an ICU during a surge period and mortality, we used two different strategies: (1) an inverse probability weighted difference-in-differences model limited to appropriately matched surge and non-surge patients and (2) a meta-regression of 50 multivariable difference-in-differences models (each based on sets of randomly matched surge- and non-surge hospitals). In the first analysis, we considered a single surge period for the cohort (March 23 - May 6). In the second, each surge hospital had its own surge period (which was compared to the same time periods in matched non-surge hospitals).Our cohort consisted of 4342 ICU patients (average age 60.8 [sd 14.8], 63.5% men) in 53 U.S. hospitals. Of these, 13 hospitals encountered surge conditions. In analysis 1, the increase in mortality seen during surge was not statistically significant (odds ratio [95% CI]: 1.30 [0.47-3.58], p = .6). In analysis 2, surge was associated with an increased odds of death (odds ratio 1.39 [95% CI, 1.34-1.43], p < .001). CONCLUSIONS: Admission to an ICU with COVID-19 in a hospital that is experiencing surge conditions may be associated with an increased odds of death. Given the high incidence of COVID-19, such increases would translate into substantial excess mortality.

Kidney Recovery and Death in Critically Ill Patients With COVID-19-Associated Acute Kidney Injury Treated With Dialysis: The STOP-COVID Cohort Study.

RATIONALE & OBJECTIVE: Acute kidney injury treated with kidney replacement therapy (AKI-KRT) occurs frequently in critically ill patients with coronavirus disease 2019 (COVID-19). We examined the clinical factors that determine kidney recovery in this population. STUDY DESIGN: Multicenter cohort study. SETTING & PARTICIPANTS: 4,221 adults not receiving KRT who were admitted to intensive care units at 68 US hospitals with COVID-19 from March 1 to June 22, 2020 (the "ICU cohort"). Among these, 876 developed AKI-KRT after admission to the ICU (the "AKI-KRT subcohort"). EXPOSURE: The ICU cohort was analyzed using AKI severity as the exposure. For the AKI-KRT subcohort, exposures included demographics, comorbidities, initial mode of KRT, and markers of illness severity at the time of KRT initiation. OUTCOME: The outcome for the ICU cohort was estimated glomerular filtration rate (eGFR) at hospital discharge. A 3-level outcome (death, kidney nonrecovery, and kidney recovery at discharge) was analyzed for the AKI-KRT subcohort. ANALYTICAL APPROACH: The ICU cohort was characterized using descriptive analyses. The AKI-KRT subcohort was characterized with both descriptive analyses and multinomial logistic regression to assess factors associated with kidney nonrecovery while accounting for death. RESULTS: Among a total of 4,221 patients in the ICU cohort, 2,361 (56%) developed AKI, including 876 (21%) who received KRT. More severe AKI was associated with higher mortality. Among survivors, more severe AKI was associated with an increased rate of kidney nonrecovery and lower kidney function at discharge. Among the 876 patients with AKI-KRT, 588 (67%) died, 95 (11%) had kidney nonrecovery, and 193 (22%) had kidney recovery by the time of discharge. The odds of kidney nonrecovery was greater for lower baseline eGFR, with ORs of 2.09 (95% CI, 1.09-4.04), 4.27 (95% CI, 1.99-9.17), and 8.69 (95% CI, 3.07-24.55) for baseline eGFR 31-60, 16-30, ≤15 mL/min/1.73 m2, respectively, compared with eGFR > 60 mL/min/1.73 m2. Oliguria at the time of KRT initiation was also associated with nonrecovery (ORs of 2.10 [95% CI, 1.14-3.88] and 4.02 [95% CI, 1.72-9.39] for patients with 50-499 and <50 mL/d of urine, respectively, compared to ≥500 mL/d of urine). LIMITATIONS: Later recovery events may not have been captured due to lack of postdischarge follow-up. CONCLUSIONS: Lower baseline eGFR and reduced urine output at the time of KRT initiation are each strongly and independently associated with kidney nonrecovery among critically ill patients with COVID-19.

Machine Learning Prediction of Death in Critically Ill Patients With Coronavirus Disease 2019.

OBJECTIVES: Critically ill patients with coronavirus disease 2019 have variable mortality. Risk scores could improve care and be used for prognostic enrichment in trials. We aimed to compare machine learning algorithms and develop a simple tool for predicting 28-day mortality in ICU patients with coronavirus disease 2019. DESIGN: This was an observational study of adult patients with coronavirus disease 2019. The primary outcome was 28-day inhospital mortality. Machine learning models and a simple tool were derived using variables from the first 48 hours of ICU admission and validated externally in independent sites and temporally with more recent admissions. Models were compared with a modified Sequential Organ Failure Assessment score, National Early Warning Score, and CURB-65 using the area under the receiver operating characteristic curve and calibration. SETTING: Sixty-eight U.S. ICUs. PATIENTS: Adults with coronavirus disease 2019 admitted to 68 ICUs in the United States between March 4, 2020, and June 29, 2020. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The study included 5,075 patients, 1,846 (36.4%) of whom died by day 28. eXtreme Gradient Boosting had the highest area under the receiver operating characteristic curve in external validation (0.81) and was well-calibrated, while k-nearest neighbors were the lowest performing machine learning algorithm (area under the receiver operating characteristic curve 0.69). Findings were similar with temporal validation. The simple tool, which was created using the most important features from the eXtreme Gradient Boosting model, had a significantly higher area under the receiver operating characteristic curve in external validation (0.78) than the Sequential Organ Failure Assessment score (0.69), National Early Warning Score (0.60), and CURB-65 (0.65; p < 0.05 for all comparisons). Age, number of ICU beds, creatinine, lactate, arterial pH, and Pao2/Fio2 ratio were the most important predictors in the eXtreme Gradient Boosting model. CONCLUSIONS: eXtreme Gradient Boosting had the highest discrimination overall, and our simple tool had higher discrimination than a modified Sequential Organ Failure Assessment score, National Early Warning Score, and CURB-65 on external validation. These models could be used to improve triage decisions and clinical trial enrichment.

Performance of crisis standards of care guidelines in a cohort of critically ill COVID-19 patients in the United States.

Many US states published crisis standards of care (CSC) guidelines for allocating scarce critical care resources during the COVID-19 pandemic. However, the performance of these guidelines in maximizing their population benefit has not been well tested. In 2,272 adults with COVID-19 requiring mechanical ventilation drawn from the Study of the Treatment and Outcomes in Critically Ill Patients with COVID-19 (STOP-COVID) multicenter cohort, we test the following three approaches to CSC algorithms: Sequential Organ Failure Assessment (SOFA) scores grouped into ranges, SOFA score ranges plus comorbidities, and a hypothetical approach using raw SOFA scores not grouped into ranges. We find that area under receiver operating characteristic (AUROC) curves for all three algorithms demonstrate only modest discrimination for 28-day mortality. Adding comorbidity scoring modestly improves algorithm performance over SOFA scores alone. The algorithm incorporating comorbidities has modestly worse predictive performance for Black compared to white patients. CSC algorithms should be empirically examined to refine approaches to the allocation of scarce resources during pandemics and to avoid potential exacerbation of racial inequities.

Prone Positioning and Survival in Mechanically Ventilated Patients With Coronavirus Disease 2019-Related Respiratory Failure.

OBJECTIVES: Therapies for patients with respiratory failure from coronavirus disease 2019 are urgently needed. Early implementation of prone positioning ventilation improves survival in patients with acute respiratory distress syndrome, but studies examining the effect of proning on survival in patients with coronavirus disease 2019 are lacking. Our objective was to estimate the effect of early proning initiation on survival in patients with coronavirus disease 2019-associated respiratory failure. DESIGN: Data were derived from the Study of the Treatment and Outcomes in Critically Ill Patients with coronavirus disease 2019, a multicenter cohort study of critically ill adults with coronavirus disease 2019 admitted to 68 U.S. hospitals. Using these data, we emulated a target trial of prone positioning ventilation by categorizing mechanically ventilated hypoxemic (ratio of Pao2 over the corresponding Fio2 ≤ 200 mm Hg) patients as having been initiated on proning or not within 2 days of ICU admission. We fit an inverse probability-weighted Cox model to estimate the mortality hazard ratio for early proning versus no early proning. Patients were followed until death, hospital discharge, or end of follow-up. SETTING: ICUs at 68 U.S. sites. PATIENTS: Critically ill adults with laboratory-confirmed coronavirus disease 2019 receiving invasive mechanical ventilation with ratio of Pao2 over the corresponding Fio2 less than or equal to 200 mm Hg. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Among 2,338 eligible patients, 702 (30.0%) were proned within the first 2 days of ICU admission. After inverse probability weighting, baseline and severity of illness characteristics were well-balanced between groups. A total of 1,017 (43.5%) of the 2,338 patients were discharged alive, 1,101 (47.1%) died, and 220 (9.4%) were still hospitalized at last follow-up. Patients proned within the first 2 days of ICU admission had a lower adjusted risk of death compared with nonproned patients (hazard ratio, 0.84; 95% CI, 0.73-0.97). CONCLUSIONS: In-hospital mortality was lower in mechanically ventilated hypoxemic patients with coronavirus disease 2019 treated with early proning compared with patients whose treatment did not include early proning.

Interleukin-6 Perpetrator of the COVID-19 Cytokine Storm.

COVID-19 has emerged as a global pandemic. It is mainly manifested as pneumonia which may deteriorate into severe respiratory failure. The major hallmark of the disease is the systemic inflammatory immune response characterized by Cytokine Storm (CS). CS is marked by elevated levels of inflammatory cytokines, mainly interleukin-6 (IL-6), IL-8, IL-10, tumour necrosis factor-α (TNF-α) and interferon-γ (IFN-γ). Of these, IL-6 is found to be significantly associated with higher mortality. IL-6 is also a robust marker for predicting disease prognosis and deterioration of clinical profile. In this review, the pivotal role played by IL-6 in the immuno-pathology of COVID-19 has been illustrated. The role of IL-6 as a pleiotropic cytokine executing both pro and anti-inflammatory activities has been reviewed. ADAM 10, a metalloproteinase switches the anti-inflammatory pathway of IL-6 to pro inflammatory hence blocking the action of ADAM 10 could be a new therapeutic strategy to mitigate the proinflammatory action of IL-6. Furthermore, we explore the role of anti-IL6 agents, IL-6 receptor antibodies which were being used for autoimmune diseases but now are being repurposed for the therapy of COVID-19.

Obesity, inflammatory and thrombotic markers, and major clinical outcomes in critically ill patients with COVID-19 in the US.

OBJECTIVE: This study aimed to determine whether obesity is independently associated with major adverse clinical outcomes and inflammatory and thrombotic markers in critically ill patients with COVID-19. METHODS: The primary outcome was in-hospital mortality in adults with COVID-19 admitted to intensive care units across the US. Secondary outcomes were acute respiratory distress syndrome (ARDS), acute kidney injury requiring renal replacement therapy (AKI-RRT), thrombotic events, and seven blood markers of inflammation and thrombosis. Unadjusted and multivariable-adjusted models were used. RESULTS: Among the 4,908 study patients, mean (SD) age was 60.9 (14.7) years, 3,095 (62.8%) were male, and 2,552 (52.0%) had obesity. In multivariable models, BMI was not associated with mortality. Higher BMI beginning at 25 kg/m2 was associated with a greater risk of ARDS and AKI-RRT but not thrombosis. There was no clinically significant association between BMI and inflammatory or thrombotic markers. CONCLUSIONS: In critically ill patients with COVID-19, higher BMI was not associated with death or thrombotic events but was associated with a greater risk of ARDS and AKI-RRT. The lack of an association between BMI and circulating biomarkers calls into question the paradigm that obesity contributes to poor outcomes in critically ill patients with COVID-19 by upregulating systemic inflammatory and prothrombotic pathways.

Identification of Distinct Clinical Subphenotypes in Critically Ill Patients With COVID-19.

BACKGROUND: Subphenotypes have been identified in patients with sepsis and ARDS and are associated with different outcomes and responses to therapies. RESEARCH QUESTION: Can unique subphenotypes be identified among critically ill patients with COVID-19? STUDY DESIGN AND METHODS: Using data from a multicenter cohort study that enrolled critically ill patients with COVID-19 from 67 hospitals across the United States, we randomly divided centers into discovery and replication cohorts. We used latent class analysis independently in each cohort to identify subphenotypes based on clinical and laboratory variables. We then analyzed the associations of subphenotypes with 28-day mortality. RESULTS: Latent class analysis identified four subphenotypes (SP) with consistent characteristics across the discovery (45 centers; n = 2,188) and replication (22 centers; n = 1,112) cohorts. SP1 was characterized by shock, acidemia, and multiorgan dysfunction, including acute kidney injury treated with renal replacement therapy. SP2 was characterized by high C-reactive protein, early need for mechanical ventilation, and the highest rate of ARDS. SP3 showed the highest burden of chronic diseases, whereas SP4 demonstrated limited chronic disease burden and mild physiologic abnormalities. Twenty-eight-day mortality in the discovery cohort ranged from 20.6% (SP4) to 52.9% (SP1). Mortality across subphenotypes remained different after adjustment for demographics, comorbidities, organ dysfunction and illness severity, regional and hospital factors. Compared with SP4, the relative risks were as follows: SP1, 1.67 (95% CI, 1.36-2.03); SP2, 1.39 (95% CI, 1.17-1.65); and SP3, 1.39 (95% CI, 1.15-1.67). Findings were similar in the replication cohort. INTERPRETATION: We identified four subphenotypes of COVID-19 critical illness with distinct patterns of clinical and laboratory characteristics, comorbidity burden, and mortality.