Background
As of May 15, 2020, the United States has reported the greatest number of coronavirus 49
disease 2019 (COVID-19) cases and deaths globally. 50
Objective
To describe risk factors for severe outcomes among adults hospitalized with COVID-19. 51
Design: Cohort study of patients identified through the Coronavirus Disease 2019-Associated 52
Hospitalization Surveillance Network. 53
Setting: 154 acute care hospitals in 74 counties in 13 states. 54
Patients: 2491 patients hospitalized with laboratory-confirmed COVID-19 during March 1–May 2, 2020. 55
Measurements: Age, sex, race/ethnicity, and underlying medical conditions. 56
Results
Ninety-two percent of patients had ≥1 underlying condition; 32% required intensive care unit 57
(ICU) admission; 19% invasive mechanical ventilation; 15% vasopressors; and 17% died during 58
hospitalization. Independent factors associated with ICU admission included ages 50-64, 65-74, 75-84 59
and ≥85 years versus 18-39 years (adjusted risk ratio (aRR) 1.53, 1.65, 1.84 and 1.43, respectively); male 60
sex (aRR 1.34); obesity (aRR 1.31); immunosuppression (aRR 1.29); and diabetes (aRR 1.13). 61
Independent factors associated with in-hospital mortality included ages 50-64, 65-74, 75-84 and ≥85 62
years versus 18-39 years (aRR 3.11, 5.77, 7.67 and 10.98, respectively); male sex (aRR 1.30); 63
immunosuppression (aRR 1.39); renal disease (aRR 1.33); chronic lung disease (aRR 1.31); cardiovascular 64
disease (aRR 1.28); neurologic disorders (aRR 1.25); and diabetes (aRR 1.19). Race/ethnicity was not 65
associated with either ICU admission or death. 66
Limitation
Data were limited to patients who were discharged or died in-hospital and had complete 67
chart abstractions; patients who were still hospitalized or did not have accessible medical records were 68
excluded. 69
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Conclusion
In-hospital mortality for COVID-19 increased markedly with increasing age. These data help 70
to characterize persons at highest risk for severe COVID-19-associated outcomes and define target 71
groups for prevention and treatment strategies. 72
73
Funding Source: This work was supported by grant CK17-1701 from the Centers of Disease Control and 74
Prevention through an Emerging Infections Program cooperative agreement and by Cooperative 75
Agreement Number NU38OT000297-02-00 awarded to the Council of State and Territorial 76
Epidemiologists from the Centers for Disease Control and Prevention. 77
78
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4
Introduction
79
In December 2019, an outbreak of a novel coronavirus disease, termed coronavirus disease-80
2019 (COVID-19), was reported in China caused by a newly identified coronavirus, severe acute 81
respiratory syndrome coronavirus-2 (SARS-CoV-2). Since then, approximately 4.5 million cases of 82
COVID-19 have been reported globally (1). As of May 15, approximately 1.4 million cases, including 83
nearly 86,000 deaths, have been reported in the United States, and case counts continue to rise (1) with 84
evidence of widespread community transmission (2). 85
Previous reports from China, Italy, and New York City have demonstrated that hospitalized 86
patients are generally older and have underlying medical conditions, such as hypertension and diabetes 87
(3-5). These studies have also found that older patients and those with certain underlying medical 88
conditions like diabetes were at higher risk for severe outcomes (3, 6, 7). Among cases reported to the 89
U.S. Centers for Disease Control and Prevention (CDC) from local and state health departments, the 90
prevalence of underlying medical conditions increased as severity of infections increased (8, 9), although 91
findings were limited by missing or incomplete information. Questions remain about the independent 92
association of sex, race/ethnicity and specific underlying conditions with severe outcomes among 93
persons hospitalized with COVID-19, after adjusting for age and other important potential confounders. 94
Comprehensive data on U.S. patients with severe COVID-19 infections are needed to better 95
inform clinicians’ understanding of groups at risk for poor outcomes and to inform current prevention 96
efforts and future interventions. We rapidly implemented population-based surveillance for laboratory-97
confirmed COVID-19-associated hospitalizations, collecting clinical data from hospitalized patients in 154 98
hospitals in 13 states since March 1, 2020. In this interim analysis restricted to patients who were 99
discharged or died in-hospital and had completed medical chart abstractions, we describe the 100
characteristics of U.S. adults hospitalized with COVID-19 and assess risk factors for intensive care unit 101
(ICU) admission and in-hospital mortality. 102
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103
Methods
104
Surveillance Overview 105
The Coronavirus Disease 2019-Associated Hospitalization Surveillance Network (COVID-NET) has 106
been previously described (10). Eligible COVID-19-associated hospitalizations occurred among persons 107
who (1) resided in a pre-defined surveillance catchment area; and (2) had a positive SARS-CoV-2 test 108
within 14 days prior to or during hospitalization. Hospitalization was defined as admission to an 109
inpatient ward for any length of time, an observation unit stay for ≥24 hours, or a combined stay in an 110
emergency department and observation unit for ≥24 hours. 111
COVID-NET surveillance occurs in acute care hospitals within 99 counties located in 14 states 112
(California, Colorado, Connecticut, Georgia, Iowa, Maryland, Michigan, Minnesota, New Mexico, New 113
York, Ohio, Oregon, Tennessee, and Utah), covering a catchment population of approximately 32 million 114
persons (~10% of the U.S. population). Although COVID-NET includes all age groups, for this analysis, we 115
excluded children <18 years of age due to small counts (n=101) and one surveillance site (Iowa) for 116
which medical chart abstractions were not conducted on identified cases. We also excluded patients 117
who were still hospitalized at the time of this analysis and all patients for whom medical chart 118
abstractions had not yet been completed. Because the COVID-19 pandemic limited the ability of 119
surveillance officers to access medical records at facilities, patients were more likely to be included in 120
this analysis if they were hospitalized at facilities that provided surveillance officers remote chart access, 121
participated in Health Information Exchanges, or were able to mail or fax records. COVID-NET 122
surveillance was initiated for cases with hospital admission on or after March 1, 2020. 123
Laboratory-confirmed COVID-19-associated hospitalizations were identified using laboratory 124
and reportable condition databases, hospital infection control databases, electronic medical records, 125
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and/or review of hospital discharge records. Laboratory tests were ordered at the discretion of the 126
treating healthcare provider. 127
Medical chart reviews for demographic and clinical data were conducted by trained surveillance 128
officers using a standard case report form. Underlying medical conditions were categorized into major 129
groups (Appendix Table 1). Obesity and severe obesity were defined as a calculated body mass index 130
(BMI) ≥30 kg/m2 and BMI ≥40 kg/m2, respectively. Chest radiograph results were obtained from the 131
radiology reports and not from review of the original radiograph. We defined severe outcomes as either 132
ICU admission or in-hospital mortality. We hypothesized that increasing age and underlying medical 133
conditions would be associated with an increased risk of ICU admission and in-hospital mortality. 134
135
Statistical Analysis 136
After the exclusions noted above, we included adults hospitalized within 154 acute care 137
hospitals in 74 counties in 13 states with an admission date during March 1–May 2, 2020 who had either 138
been discharged from the hospital or died during hospitalization and had complete medical chart 139
abstractions. We calculated proportions using the number of patients with data available on each 140
characteristic as the denominator. 141
To construct multivariable models for ICU admission and in-hospital mortality, we first assessed 142
collinearity among underlying medical condition categories and outpatient use of ACE-inhibitors and 143
ARBs. We examined the association of demographic factors, underlying medical conditions, and 144
outpatient use of ACE-inhibitors and ARBs with ICU admission and in-hospital death using chi square 145
tests. Variables considered for inclusion in the final models included current or former smoker, 146
hypertension, obesity, diabetes, chronic lung disease (CLD), cardiovascular disease (CVD) (excluding 147
hypertension), neurologic disorders, renal disease, immunosuppression, gastrointestinal/liver disease, 148
hematologic conditions, rheumatologic/autoimmune conditions, and outpatient use of ACE-inhibitors or 149
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ARBs. All multivariable models included age categorized into the following groups (18–39, 40–49, 50–150
64, 65–74, 75–84, and ≥85 years), sex, and race/ethnicity. Other variables with p-values <0.10 in 151
bivariate analyses were included in the multivariable analyses. Log-linked Poisson generalized 152
estimating equations regression with an exchangeable correlation matrix (11, 12), clustered by site, was 153
used to generate adjusted risk ratios (aRR), 95% confidence intervals (CI), and two-sided p-values for the 154
risk of ICU admission and in-hospital death. We also constructed separate multivariable models to 155
examine the association between the number of underlying medical conditions and ICU admission or in-156
hospital death. Two-sided p-values <0.05 were considered statistically significant. All analyses were 157
performed using the SAS 9.4 software (SAS Institute Inc., Cary, NC, USA). 158
These data were collected as part of routine public health surveillance and determined to be 159
non-research by CDC. Participating sites obtained approval for the COVID-NET surveillance protocol 160
from their respective state and local IRBs, as required. 161
162
Role of the Funding Source 163
This work was supported by grant CK17-1701 from the CDC through an Emerging Infections 164
Program cooperative agreement and by cooperative agreement NU38OT000297-02-00 awarded to the 165
Council of State and Territorial Epidemiologists from the CDC. 166
167
Results
168
A total of 16,318 hospitalized COVID-19 patients were reported to COVID-NET with an admission 169
date during March 1–May 2, 2020. After excluding 101 pediatric patients, 74 patients from Iowa where 170
detailed medical chart abstractions are not conducted, and 13,652 patients who were either still 171
hospitalized or did not yet have completed medical chart abstractions, 2,491 (15%) COVID-19-associated 172
hospitalized adults from 13 surveillance sites were included in this analysis (Figure 1). Patients came 173
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from 43% (154/357) of the acute care hospitals included in COVID-NET surveillance across the 13 174
surveillance sites (Appendix Table 2). The percentage of facilities contributing data out of the total 175
number of facilities by site ranged from 19% to 100%. The median age of included and excluded 176
patients (62 vs. 63 years, respectively) was similar (Appendix Table 3). The highest proportion of 177
patients included in this analysis were from Minnesota (20%), Tennessee (20%), New York (12%), and 178
Maryland (10%), and Connecticut (9%) (Appendix Table 3). 179
180
Characteristics of hospitalized patients with COVID-19 181
Among the 2,491 hospitalized adults, median age was 62 years (interquartile range (IQR), 50–182
75), and almost 75% were ≥50 years (Table 1). Forty-seven percent of patients (n=1178/2490) were 183
non-Hispanic whites, 30% non-Hispanic blacks (n=755/2490), and 12% Hispanics (n=306/2490). Nearly 184
one-third of patients were current or former smokers. 185
Almost all patients (n=2278/2489, 92%) had ≥1 underlying medical condition, with hypertension 186
(n=1428/2488, 57%), obesity (n=1154/2332, 50%), and chronic metabolic disease (n=1024/2486, 187
41%) most frequently documented. Among patients with chronic metabolic disease, 80% (n=819/1024) 188
had diabetes mellitus; hypertension alone was documented in only 4% (n=91/2490) of patients. 189
Seventeen percent (n=316/1892) took ACE-inhibitors, and 14% (n=257/1895) took ARBs prior to 190
hospitalization. The proportion of patients with any documented underlying medical condition 191
increased with age (p<0.05)(Figure 2A). Prevalence of CLD, neurologic conditions, obesity, and renal 192
disease varied between males and females (p<0.05, Figure 2B). CVD, CLD, and neurologic conditions 193
were more prevalent among non-Hispanic whites, while diabetes, hypertension, obesity and renal 194
disease were more common among non-Hispanic blacks (p<0.05, Figure 2C). 195
Cough (75%), fever or chills (74%), and shortness of breath (70%) were commonly 196
documented symptoms at admission (Table 2 and Appendix Table 4). Gastrointestinal symptoms, 197
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including nausea, vomiting, and diarrhea, were documented in almost 30% of patients. Median length 198
of hospitalization was 6 days (IQR, 3–11), and median days from symptom onset to hospital admission 199
was 6 days (IQR, 3–8). Median values of initial vital signs were within normal range, except for elevated 200
blood pressure (Table 2). Thirty-three individuals had a pathogen detected from positive blood cultures 201
(Appendix Table 5). Viral co-detections from respiratory specimens were rare among those who were 202
tested (n=38/1549, 2.5%) (Appendix Table 6). Among 1932 patients with chest radiograph 203
performed, 92% (n=1769) were documented as abnormal with infiltrate or consolidation (n=1574/1932, 204
81%) documented most frequently (Appendix Table 7). Ninety-five percent (n=540/566) of patients with 205
chest computerized tomography (CT) had abnormal findings, and ground glass opacity 206
was documented in 62% (n=350/566) (Appendix Table 7). 207
Forty-five percent (n=1125/2482) of patients received investigational medication regimens for 208
COVID-19 during hospitalization (Table 2). The most common regimens included hydroxychloroquine 209
(n=1065/2479, 43%) and the combination of azithromycin and ≥1 COVID-19 treatment (n=725/2479, 210
29%) (non-mutually exclusive categories). The most frequent discharge diagnoses recorded in hospital 211
discharge summaries were pneumonia (n=1395/2485, 56%), acute respiratory failure (n=999/2487, 212
40%), acute renal failure (n=456/2,485, 18%), and sepsis (n=443/2,479, 18%). 213
Thirty-two percent (n=798/2490) of patients required ICU admission, with a median length of 214
ICU stay of 6 days (range, 1-41; IQR, 2–11) (Table 2). Median days from symptom onset to ICU 215
admission was 7 days (range, 0–25; IQR, 4–10), and median days from hospital admission to ICU 216
admission was 1 day (range, 0–19; IQR, 0–2). Among 2,489 hospitalized patients, the highest respiratory 217
support received was invasive mechanical ventilation in 19% (n=462), bilevel positive airway pressure 218
(BIPAP) or continuous positive airway pressure (CPAP) in 3% (n=82), and high flow nasal cannula (HFNC) 219
in 7% (n=170). Fifty-three percent (n=246/462) of patients that received invasive mechanical ventilation 220
died in-hospital (median age, 71 years; IQR, 62–79); the proportion of patients receiving mechanical 221
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ventilation who died increased with age (p<0.0001). Vasopressors were used in 15% (n=373/2486) of 222
patients, while renal replacement therapy was used in 5% (n=115/2487). As age increased, so did 223
the proportion of patients who required ICU admission, invasive mechanical ventilation, and 224
vasopressors (p<0.05, Figure 3A). Males were admitted to the ICU and treated with invasive mechanical 225
ventilation, HFNC, or vasopressors more frequently than females (p<0.05) (Figure 3B). Non-Hispanic 226
whites more frequently received BIPAP, CPAP or HFNC (p<0.05, Figure 3C). 227
Overall, seventeen percent (n=420/2490) of patients died during hospitalization (Table 2). The 228
proportion of patients who died increased with increasing age groups, ranging from 3% among 18–49 229
years to 10% among 50–64 years to 29% among ≥65 years (Figure 3A). Males died more frequently 230
compared to females (p<0.05) (Figure 3B), as did non-Hispanic whites compared to other 231
race/ethnicities (p<0.05, Figure 3C). 232
Among 420 patients who died, median age was 76 years (range, 24–97; IQR, 66–85); 58% 233
(n=244) were male; 71% (n=299) were admitted to the ICU; and 59% (n=246) received invasive 234
mechanical ventilation. The median length of hospitalization among patients who died was 7 days 235
(range, 0–40; IQR, 4–12). 236
237
Risk factors for ICU admission and death 238
Factors independently associated with ICU admission included age 50–64 years (adjusted risk 239
ratio (aRR) = 1.53; 95% confidence interval (CI), 1.28 to 1.83); 65–74 years (aRR = 1.65; CI, 1.34 to 2.03); 240
75–84 years (aRR = 1.84; CI, 1.60 to 2.11); ≥85 years (aRR = 1.43; CI, 1.00 to 2.04); male sex (aRR = 1.34; 241
CI, 1.20 to 1.50); obesity (aRR = 1.31; CI, 1.16 to 1.47); diabetes (aRR = 1.13; CI, 1.03 to 1.24); and 242
immunosuppression (aRR = 1.29; CI, 1.13 to 1.47) (Table 3A). 243
Independent factors associated with in-hospital mortality included age 50–64 years (aRR = 3.11; 244
CI 1.50 to 6.46); age 65–74 years (aRR = 5.77; CI, 2.64 to 12.64); age 75–84 years (aRR = 7.67; CI, 3.35 to 245
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17.59); age ≥85 years (aRR = 10.98; CI, 5.09 to 23.69); male sex (aRR = 1.30; CI, 1.14 to 1.49); diabetes 246
(aRR = 1.19; CI, 1.01 to 1.40); CLD (aRR = 1.31; CI, 1.13 to 1.52); CVD (aRR = 1.28; CI, 1.03 to 1.58); 247
neurologic disorders (aRR = 1.25; CI, 1.04 to 1.50); renal disease (aRR = 1.33; CI, 1.10 to 1.61); and 248
immunosuppression (aRR = 1.39; CI, 1.13 to 1.70) (Table 3B). 249
Having ≥3 underlying medical conditions was significantly associated with higher risk of 250
ICU admission and death after adjusting for age group, sex, and race/ethnicity (Appendix Table 8). 251
252
Discussion
253
Using a geographically diverse, multi-site, population-based U.S. surveillance system, we found 254
that among adults hospitalized with laboratory-confirmed COVID-19, almost one-third required ICU 255
admission, 19% received invasive mechanical ventilation, and 17% died during hospitalization. About 256
75% of patients were ≥50 years, and >90% had underlying medical conditions. Older age, being male, 257
and the presence of certain underlying medical conditions were associated with a higher risk of ICU 258
admission and in-hospital mortality. Race/ethnicity was not independently associated with either 259
outcome among hospitalized patients. This information can alert healthcare providers to patients at 260
greatest risk of severe outcomes and help target prevention strategies and future interventions. 261
In a published COVID-NET analysis, we found that when comparing the racial/ethnic distribution 262
of residents of the surveillance catchment areas to the racial/ethnic distribution of COVID-19-associated 263
hospitalizations, non-Hispanic blacks were disproportionately hospitalized with COVID-19 compared to 264
non-Hispanic whites (10). In this analysis, however, we found that once hospitalized, non-Hispanic 265
blacks did not have increased risk of poorer outcomes compared to other race/ethnicities after adjusting 266
for age and underlying conditions. In a preprinted article of U.S. Veterans seeking care at VA Hospitals, 267
Rentsch et al. found no association between black race and ICU admission (13). Similarly, a large study 268
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of patients hospitalized in New York City did not find race/ethnicity to be associated with ICU admission 269
or death (4). 270
COVID-19-associated hospitalizations, ICU admissions, and deaths have been shown to occur 271
more frequently with increasing age (6, 9, 14). In our study, age ≥65 years was the strongest 272
independent predictor of ICU admission and in-hospital mortality. Persons aged 75–84 years had the 273
highest the risk of ICU admission compared to 18-49 years old, and those ≥85 years experienced 11 274
times the risk of death. These findings are similar to other studies from China, Europe, and the United 275
States (4, 9, 14-17). Our data provide support that older persons are particularly vulnerable to severe 276
COVID-19 disease and should be targeted for aggressive preventive measures (8). 277
Being male was associated with a higher risk of ICU admission and death after adjusting for age, 278
race/ethnicity and underlying conditions. Other studies have similarly shown male sex to be associated 279
with COVID-19-associated hospitalizations (4, 18), ICU admissions (19), and need for mechanical 280
ventilation (20). 281
Similar to other U.S. studies, we found that nearly all hospitalized patients with COVID-19 had at 282
least one underlying medical condition (4). In contrast, underlying medical conditions were documented 283
in only 25–50% of hospitalized cases from China (3, 21). Our analysis further demonstrated that a higher 284
number of underlying medical conditions increased the risk of ICU admission (1.3 times the risk in 285
persons with ≥3 vs. no underlying condition) and in-hospital mortality (1.8 times the risk in persons with 286
≥3 vs. no underlying condition). 287
In a retrospective case study among 1590 laboratory-confirmed hospitalized COVID-19 cases in 288
575 Chinese hospitals, Guan et al. found that after adjusting for age and smoking status, chronic 289
obstructive pulmonary disease, diabetes, hypertension and malignancy were risk factors for a composite 290
endpoint of ICU admission, invasive mechanical ventilation, and death (3). Similarly, we found an 291
association between underlying medical conditions and severe outcomes, with diabetes, CLD, CVD, 292
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neurologic disease, renal disease and immunosuppression associated with in-hospital death, and 293
diabetes, obesity, and immunosuppression associated with ICU admission. While hypertension was 294
highly prevalent in our patient population, it was not associated with ICU admission or death. Additional 295
studies are needed to determine whether hypertension, which is also highly prevalent in the U.S. 296
population, increases the risk of COVID-19-associated hospitalizations and whether the duration of 297
hypertension and the degree to which it is controlled impact the risk for severe COVID-19 disease. 298
Similarly, the associations between the duration and degree of glycemic control in diabetes and severity 299
of COVID-19 disease require further investigation. Obesity, which was also highly prevalent in this 300
cohort, imparted increased risk for ICU admission, but not death. This finding may, in part, be explained 301
by a trend of decreasing obesity prevalence with increasing age, which was a strong risk factor for 302
mortality. Healthcare providers should be aware of these findings to appropriately triage and manage 303
patients with high-risk conditions that may either increase risk for hospitalization or poorer outcomes 304
once hospitalized (22, 23). 305
We collected data on initial symptoms, vital signs and laboratory values to characterize disease 306
severity at admission. While approximately 70% of patients had shortness of breath at admission, the 307
median oxygen saturation at admission was 94% on room air. Other admission vital signs and laboratory 308
values were also largely within normal ranges. Because we did not collect data on vital signs or 309
laboratory values during the hospital course, we may not have fully captured the onset of clinical 310
deterioration that has been reported during the second week after illness onset (24). We limited our 311
analysis to patients that had either been discharged or died in-hospital and found that 15% of patients 312
received vasopressor support, and 19% received invasive mechanical ventilation. Other U.S. studies 313
have found that up to 32% of hospitalized patients have received vasopressors and 29–33% have 314
received invasive mechanical ventilation (19, 20), though some of these studies included patients who 315
were still hospitalized at the time of analysis. In our study, 53% of patients requiring mechanical 316
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14
ventilation died, which is higher than the 36% reported in a recent study from New York City (4). In 317
general, the proportion of patients with severe outcomes was higher in the United States than reported 318
from China (6). Differences between patients’ outcomes in the United States and China may reflect 319
differences in clinical practices or varying thresholds for hospitalization (18). These proportions of 320
severe outcomes among U.S. patients are also generally higher than those found in U.S. adults 321
hospitalized with seasonal influenza (25, 26). Our findings may help to inform resource planning and 322
allocation in healthcare facilities during the COVID-19 pandemic. 323
There are several limitations to our analysis. First, it is likely that not all COVID-19-associated 324
hospitalizations were captured because of the lack of widespread testing capability during the study 325
period and because identification of COVID-19 patients was largely reliant on clinician-directed testing. 326
Second, clinical practices and availability of specific interventions may differ across hospitals, which 327
might have influenced findings. Third, COVID-NET is an ongoing surveillance system, and only 15% of 328
the 16,318 COVID-19 hospitalized patients were included, representing those who were discharged or 329
died in-hospital during March 1–May 2, 2020 and for whom medical records were available and chart 330
abstractions were completed. These restrictions may have resulted in selection bias. However, there 331
was no difference in the age and sex distribution between cases included and excluded from the 332
analysis. The geographic distribution of cases included versus excluded from this analysis differed, 333
which may have impacted the racial and ethnic distribution of cases included in this analysis as 334
compared to the racial and ethnic distribution of the surveillance catchment population; however, as we 335
do not yet have complete data on race/ethnicity for all identified cases, we were not able to assess this 336
further. Nevertheless, COVID-NET encompasses a large geographic area with multiple hospitals and 337
likely offers a more racially and ethnically diverse patient population compared to other single-center or 338
state-based studies. Lastly, small counts limited our ability to determine risk factors for severe 339
outcomes among all racial and ethnic groups. COVID-NET data will become more robust as additional 340
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medical chart reviews are completed and may allow further investigation within these racial and ethnic 341
groups over time. 342
Based on preliminary findings from this multi-site, geographically diverse study, a high 343
proportion of patients hospitalized with COVID-19 received aggressive interventions and had poor 344
outcomes. Increasing age was the strongest predictor of in-hospital mortality. Prevention strategies, 345
such as social distancing and rigorous hand hygiene, are key to minimizing the risk of infection in high-346
risk patients. These data help to characterize persons at highest risk for severe COVID-19-associated 347
disease in the United States and to define target groups for future prevention and treatment strategies 348
as they become available. 349
350
ACKNOWLEDGMENTS 351
Ashley Coates, Pam Daily Kirley, Gretchen Rothrock, California Emerging Infections Program; Nisha 352
Alden, Rachel Herlihy, Breanna Kawasaki, Colorado Department of Public Health and Environment; Paula 353
Clogher, Hazal Kayalioglu, Amber Maslar, Adam Misiorski, Danyel Olson, Christina Parisi, Connecticut 354
Emerging Infections Program; Kyle Openo, Emily Fawcett, Jeremiah Williams, Katelyn Lengacher, Georgia 355
Emerging Infections Program; Andrew Weigel, Iowa Department of Health; Brian Bachaus, Timothy 356
Blood, David Blythe, Alicia Brooks, Judie Hyun, Elisabeth Vaeth, Cindy Zerrlaut, Maryland Department of 357
Health; Jim Collins, Kimberly Fox, Sam Hawkins, Justin Henderson, Shannon Johnson, Libby Reeg, 358
Michigan Department of Health and Human Services; Austin Bell, Kayla Bilski, Erica Bye, Emma 359
Contestabile, Richard Danila, Kristen Ehresmann, Hannah Friedlander, Claire Henrichsen, Emily 360
Holodnick, Ruth Lynfield, Katherine Schliess, Samantha Siebman, Kirk Smith, Maureen Sullivan, 361
Minnesota Department of Health; Cory Cline, New Mexico Department of Health; Kathy Angeles, Lisa 362
Butler, Emily Hancock, Sarah Khanlian, Meaghan Novi, Sarah Shrum, New Mexico Emerging Infections 363
Program Albuquerque; Nancy Spina, Grant Barney, Suzanne McGuire, New York State Health 364
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Department; Sophrena Bushey, Christina Felsen, Maria Gaitan, Anita Gellert, RaeAnne Kurtz, Christine 365
Long, Shantel Peters, Marissa Tracy, University of Rochester School of Medicine and Dentistry; Laurie 366
Billing, Maya Scullin, Jessica Shiltz, Ohio Department of Health; Nicole West, Oregon Health Authority; 367
Kathy Billings, Katie Dyer, Anise Elie, Karen Leib, Tiffanie Markus, Terri McMinn, Danielle Ndi, 368
Manideepthi Pemmaraju, Vanderbilt University Medical Center; Keegan McCaffrey, Utah Department of 369
Health; Clarissa Aquino, Ryan Chatelain, Andrea George, Jacob Ortega, Andrea Price, Ilene Risk, Melanie 370
Spencer, Ashley Swain, Salt Lake County Health Department; Mimi Huynh, Monica Schroeder, Council of 371
State and Territorial Epidemiologists; Shua J. Chai, Field Services Branch, Division of State and Local 372
Readiness, Center for Preparedness and Response, Centers for Disease Control and Prevention; Sharad 373
Aggarwal, Lanson Broecker, Aaron Curns, Rebecca M. Dahl, Alexandra Ganim, Rainy Henry, Sang Kang, 374
Sonja Nti-Berko, Robert Pinner, Mila Prill, Scott Santibanez, Alvin Shultz, Sheng-Te Tsai, Henry Walke, 375
Venkata Akesh R. Vundi, CDC. 376
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1
Figure 1. Flow diagram of analytic sample.
16,318 hospitalized COVID-NET patients reported with
admission date during March 1–May 2, 2020
16,217 hospitalized adults
2,491 (15.3%) included in analysis
Excluded 1 site’s cases
(no clinical data available)
n=74
Excluded cases due to incomplete medical
chart reviews
n=13,652
Pediatric cases
N=101
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2
Table 1. Demographic and clinical characteristics of adults hospitalized with COVID-19 — COVID-NET,
13 sites (N=2,491)
n, %
Age in years (median, IQR) 62, 50–75
Age category
18–39 302 (12.1)
40–49 319 (12.8)
50–64 744 (29.9)
65–74 478 (19.2)
75–84 397 (15.9)
85+ 251 (10.1)
Male 1,326 (53.2)
Race/ethnicity (n=2,490)
Non-Hispanic White 1,178 (47.3)
Non-Hispanic Black 755 (30.3)
Hispanic 306 (12.3)
Non-Hispanic Other* 158 (6.3)
Unknown 93 (3.7)
Residence at time of hospitalization (n=2,482)
Private residence 1,899 (76.5)
Facility† 495 (19.9)
Homeless/Shelter 40 (1.6)
Other‡ 45 (1.8)
Unknown 3 (0.1)
Smoker (n=2,489)
Current 150 (6.0)
Former 642(25.8)
No or Unknown 1,697 (68.2)
Any underlying condition§ (n=2,489) 2,278 (91.5)
Hypertension (n=2,488) 1,428 (57.4)
Obesity‖ (n=2,332) 1154 (49.7)
Severe obesity‖ (n=2,332) 325 (14.0)
Chronic metabolic disease (n=2,486) 1,024 (41.2)
Diabetes mellitus (n=2,486) 819 (32.9)
Chronic lung disease (n=2,484) 747 (30.1)
Asthma (n=2,484) 314 (12.6)
Chronic Obstructive Pulmonary Disease (n=2,484) 266 (10.7)
Cardiovascular disease (n=2,486) 859 (34.6)
Coronary artery disease (n=2,486) ¶ 352 (14.2)
Congestive heart failure (n=2,486) 284 (11.4)
Neurologic disease (n=2,484) 548 (22.1)
Renal disease (n=2,488) 386 (15.5)
Immunosuppressive condition (n=2,487) 263 (10.6)
Gastrointestinal or Liver disease (n=2,486) 118 (4.7)
Hematologic condition (n=2,483) 80 (3.2)
Rheumatologic or autoimmune disease (n=2,486) 77 (3.1)
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3
Pregnancy (n=279)** 36 (12.9)
Number of underlying medical conditions
(by major category) (n=2,490)
0 212 (8.5)
1 480 (19.3)
2 510 (20.5)
3+ 1,288 (51.7)
Outpatient use of medications
ACE-inhibitor (n=1,892) 316 (16.7)
Angiotensin receptor blockers (ARBs) (n=1,895) 257 (13.6)
IQR = interquartile range; ACE = angiotensin-converting enzyme inhibitors
*Non-Hispanic Other includes: Non-Hispanic American Indian or Alaskan Native (n=24), Non-Hispanic Asian (n=128), and Non-
Hispanic multiracial (n=6)
†Facility includes rehabilitation facilities, assisted living/residential care, group homes, nursing homes, skilled nursing facilities,
long-term care facilities, long-term acute care hospitals, alcohol/drug treatment centers, and psychiatric facilities.
‡Other includes home with services (n=43), correctional facility (n=1), and hospice (n=1).
§See Supplementary Table 1 for definitions of underlying medical conditions.
‖Obesity is defined as body mass index (BMI) ≥30 kg/m2, and severe obesity is defined as BMI ≥40 kg/m2.
¶Includes coronary artery disease, history of coronary artery bypass grafting, and history of myocardial infarction
**Denominator includes women aged 15–49 years.
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4
Figure 2. Select underlying medical conditions* of adults hospitalized with COVID-19, by age, sex, and
race/ethnicity — COVID-NET, 13 sites (N=2,491)
A. Age (n=2,489)
*p-value <0.05
CVD = Cardiovascular disease (excluding hypertension); HTN = hypertension; CLD = chronic lung disease.
B. Sex (n=2,489)
*p-value <0.05
CVD = Cardiovascular disease (excluding hypertension); HTN = hypertension; CLD = chronic lung disease.
83
8
23 22 27
7 8
66
4
91
23
31 37
57
11 16
57
10
97
57
33 37
74
12
34 36
25
0
10
20
30
40
50
60
70
80
90
100Percent (%)
Underlying Medical Condition
18-49 years 50-64 years 65+ years
89
36
28
34
58
11
20
44
17
94
33 33 32
57
10
25
56
14
0
10
20
30
40
50
60
70
80
90
100Percent (%)
Underlying Medical Condition
Male Female
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5
C. Race/Ethnicity (n=2,488)
*p-value <0.05
CVD = Cardiovascular disease (excluding hypertension); HTN = hypertension; CLD = chronic lung disease.
*The underlying medical condition categories are not mutually exclusive. Patients can have more than
once underlying medical condition.
94
42 35 30
60
12
29
45
16
95
34 32
40
63
12 19
58
20
82
13 13
30
40
7 8
54
6
0
10
20
30
40
50
60
70
80
90
100Percent (%)
Underlying Medical Condition
Non-Hispanic White Non-Hispanic Black Hispanic
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6
Table 2. Clinical course, interventions, and outcomes of adults hospitalized with COVID-19 — COVID-
NET, 13 sites (N=2,491)
%
Symptoms on admission* (n=2,482)
Cough 1,855 (74.7)
Fever or chills 1,835 (73.9)
Shortness of breath 1,740 (70.1)
Muscle aches/myalgias 722 (29.1)
Diarrhea 676 (27.2)
Nausea or vomiting 621 (25.0)
Hospitalization length of stay in days, median (IQR) (n=2,487) 6 (3–11)
Days from symptom onset to hospitalization
(median, IQR) (n=1,937) 6 (3–8)
Initial vital signs
Temperature (◦Celsius, median, IQR) (n=2,469) 37.4 (36.9–38.1)
Heart rate (median, IQR) (n=2,479) 95 (83–108)
Systolic blood pressure (median, IQR) (n=2,483) 132 (118–147)
Respiratory rate (median, IQR) (n=2,461) 20 (18–23)
Oxygen saturation (among those on room air)
(median, IQR) (n=1,969)
94 (92–97)
Initial laboratory values
White blood cell count (median, IQR) – per mm3 (n=2,458) 6.3 (4.7–8.5)
Hematocrit (median, IQR) - % (n=2,461) 40.6 (36.9–43.9)
Platelet count (median, IQR) – per mm3 (n=2,461) 195.0 (156.0–249.0)
Sodium (median, IQR) – mmol/L (n=2,460) 137.0 (134.0–139.0)
Blood Urea Nitrogen (median, IQR) – mg/dl (n=2,443) 16.0 (11.0–25.0)
Creatinine (median, IQR) – mg/dl (n=2,462) 1.0 (0.8–1.4)
Glucose (median, IQR) – mg/dl (n=2,459) 117.0 (102.0–149.0)
Aspartate transaminase (median, IQR) – U/L (n=2,149) 40.0 (28.0–61.0)
Alanine aminotransferase (median, IQR) – U/L (n=2,164) 31.0 (20.0–50.0)
Arterial pH (median, IQR) (n=487) 7.35 (7.40–7.45)
Abnormal chest X-ray during hospitalization (n=1,932) 1,769 (91.6)
Abnormal chest CT during hospitalization (n=566) 540 (95.4)
Ground glass opacities (n=566) 350 (61.8)
Investigational medication regimens for COVID-19† (n=2,482) 1,125 (45.3)
Hydroxychloroquine‡ (n=2,479) 1,065 (43.0)
Azithromycin + ≥ 1 other COVID-19 treatment (n=2,479) 725 (29.2)
Tocilizumab (n=2,479) 103 (4.2)
Atazanavir (n=2,479)§ 94 (3.8)
Remdesivir (n=2,479)‡ 53 (2.1)
Lopinavir/ritonavir (n=2,479)§ 27 (1.1)
Convalescent plasma (n=2,479) 9 (0.4)
Chloroquine (n=2,479) 7 (0.3)
Sarilumab (n=2,479)‡ 6 (0.2)
Investigational drug (not specified) RCT (n=2,479) 1 (0.0)
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7
ICU Admission (n=2,490) 798 (32.0)
ICU length of stay (days, median, IQR) (n=771) 6 (2–11)
Highest level of respiratory support required (n=2,489)
Invasive mechanical ventilation 462 (18.6)
BIPAP or CPAP 82 (3.3)
High flow nasal cannula 170 (6.8)
ECMO (n=2,487) 9 (0.4)
Vasopressor use (n=2,486) 373 (15.0)
Systemic steroids (n=2,489) 321 (12.9)
Renal replacement therapy (n=2,487) 115 (4.6)
Discharge Diagnoses‖
Pneumonia (n=2,485) 1,395 (56.1)
Acute respiratory failure (n=2,487) 999 (40.2)
Acute renal failure (n=2,485) 456 (18.4)
Sepsis (n=2,479) 443 (17.9)
Acute respiratory distress syndrome (n=2,485) 255 (10.3)
Encephalitis (n=2,482) 151 (6.1)
Congestive heart failure (n=2,485) 51 (2.1)
Asthma exacerbation (n=2,486) 43 (1.7)
COPD exacerbation (n=2,486) 39 (1.6)
Acute myocardial infarction (n=2,485) 38 (1.5)
In-hospital death (n=2,490) 420 (16.9)
IQR = interquartile range; CT = computed tomography; ICU = intensive care unit; BIPAP = bilevel positive airway pressure; CPAP
= continuous positive airway pressure; ECMO = extracorporeal membrane oxygenation; COPD = chronic obstructive pulmonary
disease
*See Supplementary Table 2 for additional symptom data.
†Not mutually exclusive categories
‡Includes randomized controlled trials where it cannot be determined whether the case received treatment vs. placebo
(remdesivir, 24; hydroxychloroquine 15; and sarilumab 5).
§Persons with HIV/AIDS were excluded.
‖Discharge diagnoses recorded from the hospital discharge summary and not based on ICD-10 discharge codes.
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8
Figure 3. Interventions and outcomes of adults hospitalized with COVID-19, by age, sex, and
race/ethnicity — COVID-NET, 13 sites (N=2,491)
A. Age (n=2,490)
*p-value <0.05
ICU = intensive care unit; BIPAP = bilevel positive airway pressure; CPAP = continuous positive airway pressure; HFNC =
high flow nasal cannula; RRT = renal replacement therapy
B. Sex (n=2,490)
ICU = intensive care unit; BIPAP = bilevel positive airway pressure; CPAP = continuous positive airway pressure; HFNC =
high flow nasal cannula; RRT = renal replacement therapy
25
11
2 7 9
3 3
34
19
4 5
15
5 10
35
23
4 8
19
5
29
0
10
20
30
40
50
60
70
80
90
100
ICU* Invasive
mechanical
ventilation*
BIPAP/CPAP HFNC* Vasopressor* RRT In-hospital
death*
Percent (%)
Interventions and outcomes
18-49 years 50-64 years 65+ years
36
21
4 8
17
5
18
28
15
3 6
13
4
15
0
10
20
30
40
50
60
70
80
90
100
ICU* Invasive
mechanical
ventilation*
BIPAP/CPAP HFNC* Vasopressor* RRT In-hospital
death*
Percent (%)
Interventions and outcomes
Male Female
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9
C. Race/Ethnicity (n=2,490)
*p-value <0.05
ICU = intensive care unit; BIPAP = bilevel positive airway pressure; CPAP = continuous positive airway pressure; HFNC =
high flow nasal cannula; RRT = renal replacement therapy
* For mechanical ventilation, BIPAP/CPAP, and HFNC, patients are assigned based on the highest level of
respiratory support required during hospitalization (i.e. invasive mechanical ventilation followed by
BIPAP or CPAP, followed by high flow nasal cannula).
32
18
4 8 15
3
20
33
20
3 5
16
8
16
28
16
1 5
13
4 8
0
10
20
30
40
50
60
70
80
90
100
ICU Invasive
mechanical
ventilation
BIPAP/CPAP* HFNC* Vasopressor RRT* In-hospital
death*
Percent (%)
Interventions and outcomes
Non-Hispanic White Non-Hispanic Black Hispanic
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10
Table 3. Risk factors for ICU admission and in-hospital mortality — COVID-NET, 13 sites (N=2,491)
A. ICU Admission (N=2,490)*
Characteristic Category Not in ICU
(n=1,692)
In ICU
(n=798)
Total
(N=2,490) P-value Unadjusted
Risk Ratio 95% CI Adjusted
Risk Ratio 95% CI
Age category
<0.0001
18–39 years 240 (14) 62 (8) 302 Reference N/A Reference N/A
40–49 years 227 (13) 91 (11) 318 1.38 (1.08, 1.75) 1.22 (0.96, 1.56)
50–64 years 488 (29) 256 (32) 744 1.64 (1.36, 1.99) 1.53 (1.28, 1.83)
65–74 years 298 (18) 180 (23) 478 1.80 (1.50, 2.16) 1.65 (1.34, 2.03)
75–84 years 248 (15) 149 (19) 397 1.80 (1.52, 2.14) 1.84 (1.6, 2.11)
85+ years 191 (11) 60 (8) 251 1.16 (0.87, 1.54) 1.43 (1.00, 2.04)†
Sex <0.0001
Female 844 (50) 320 (40) 1164 Reference N/A Reference N/A
Male 848 (50) 478 (60) 1326 1.30 (1.20, 1.42) 1.34 (1.20, 1.50)
Race/ethnicity
0.63
NH White 800 (47) 378 (47) 1178 Reference Reference N/A
NH Black 503 (30) 251 (31) 754 1.03 (0.93, 1.13) 1.01 (0.89, 1.15)
Hispanic 219 (13) 87 (11) 306 0.86 (0.69, 1.09) 0.96 (0.76, 1.21)
NH Other 105 (6) 53 (7) 158 1.03 (0.89, 1.18) 1.06 (0.83, 1.37)
Unknown 64 (4) 29 (4) 93 0.97 (0.77, 1.22) 0.93 (0.74, 1.15)
Smoker
0.0001
No/Unknown 1185 (70) 512 (64) 1697 Reference Reference N/A
Former 395 (23) 247 (31) 642 1.26 (1.10, 1.43) 1.07 (0.92, 1.24)
Current 112 (7) 38 (5) 150 0.84 (0.67, 1.06) 0.81 (0.61, 1.06)
Hypertension 0.03
No 746 (44) 314 (39) 1060 Reference Reference N/A
Yes 945 (56) 483 (61) 1428 1.13 (1.01, 1.27) 0.92 (0.79, 1.07)
Obesity
(BMI≥30)
0.0013
No 821 (53) 347 (46) 1168 Reference N/A Reference N/A
Yes 739 (47) 415 (54) 1154 1.25 (1.14, 1.37) 1.31 (1.16, 1.47)
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11
Diabetes
<0.0001
No 1176 (70) 491 (62) 1667 Reference N/A Reference N/A
Yes 513 (30) 306 (38) 819 1.20 (1.08, 1.34) 1.13 (1.03, 1.24)
Chronic Lung
Disease
<0.0001
No 1222 (72) 515 (65) 1737 Reference N/A Reference N/A
Yes 466 (28) 281 (35) 747 1.25 (1.09, 1.44) 1.17 (1.00, 1.37)‡
Cardiovascular
Disease
0.006
No 1136 (67) 491 (62) 1627 Reference N/A Reference N/A
Yes 553 (33) 306 (38) 859 1.17 (1.09, 1.26) 0.98 (0.88, 1.09)
Neurologic 0.06
No 1297 (77) 639 (80) 1936 Reference N/A Reference N/A
Yes 390 (23) 158 (20) 548 0.88 (0.76, 1.03) 0.85 (0.70, 1.04)
Renal
0.004
No 1453 (86) 649 (81) 2102 Reference N/A Reference N/A
Yes 238 (14) 148 (19) 386 1.23 (1.11, 1.37) 1.05 (0.94, 1.16)
Immuno-
suppression
<0.0001
No 1541 (91) 683 (86) 2224 Reference N/A Reference N/A
Yes 149 (9) 114 (14) 263 1.39 (1.22, 1.58) 1.29 (1.13, 1.47)
Gastro-
intestinal or
Liver
0.87
No 1609 (95) 759 (95) 2368 Reference N/A N/A N/A
Yes 81 (5) 37 (5) 118 0.98 (0.80, 1.20) N/A N/A
Hematologic
0.87
No 1632 (97) 771 (97) 2403 Reference N/A N/A N/A
Yes 55 (3) 25 (3) 80 0.96 (0.76, 1.22) N/A N/A
Rheumatologic
or
Autoimmune
0.87
No 1637 (97) 772 (97) 2409 Reference N/A N/A N/A
Yes 53 (3) 24 (3) 77 0.96 (0.74, 1.26) N/A N/A
Outpatient
ACE-Inhibitor
Use
0.99
No/Unknown 1063 (83) 513 (83) 1576 Reference N/A N/A N/A
Yes 213 (17) 103 (17) 316 0.99 (0.84, 1.18) N/A N/A
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12
Outpatient
Angiotensin
Receptor
Blocker Use
0.04
No/Unknown 1118 (88) 520 (84) 1638 Reference N/A Reference N/A
Yes 159 (12) 98 (16) 257 1.18 (1.06, 1.31) 1.07 (0.95, 1.21)
ICU = intensive care unit; CI = confidence interval; N/A = not applicable; ACE = angiotensin-converting-enzyme
*Final model included age, sex, race/ethnicity, smoking status, hypertension, obesity, diabetes, chronic lung disease, cardiovascular disease, neurologic disease, renal disease,
immunosuppression, and outpatient use of an angiotensin receptor blocker.
†p=0.0494
‡p=0.0524
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13
B. In-hospital mortality (N=2,490)*
Characteristic Category
Discharged
Alive
(n=2070)
In-Hospital
Death
(n=420)
Total
(N=2490) P-value Unadjusted
Risk Ratio 95% CI Adjusted
Risk Ratio 95% CI
Age
<0.0001
18-39 years 296 (14) 6 (1) 302 Reference N/A Reference N/A
40–49 years 308 (15) 10 (2) 318 1.51 (0.59, 3.85) 1.23 (0.51, 2.99)
50-64 years 670 (32) 74 (18) 744 4.62 (2.1, 10.18) 3.11 (1.50, 6.46)
65–74 years 375 (18) 103 (25) 478 9.88 (4.28, 22.85) 5.77 (2.64, 12.64)
75–84 years 277 (13) 120 (29) 397 13.89 (6.12, 31.52) 7.67 (3.35, 17.59)
85+ years 144 (7) 107 (25) 251 19.46 (9.39, 40.35) 10.98 (5.09, 23.69)
Sex 0.03
Female 988 (48) 176 (42) 1164 Reference N/A Reference N/A
Male 1082 (52) 244 (58) 1326 1.22 (1.02, 1.47) 1.30 (1.14, 1.49)
Race/ethnicity
<0.0001
NH White 944 (46) 234 (56) 1178 Reference N/A Reference N/A
NH Black 637 (31) 117 (28) 754 0.75 (0.57, 0.99) 1.07 (0.85, 1.35)
Hispanic 281 (14) 25 (6) 306 0.42 (0.32, 0.56) 1.17 (0.91, 1.51)
NH Other 132 (6) 26 (6) 158 0.82 (0.54, 1.25) 1.26 (0.86, 1.82)
Unknown 76 (4) 17 (4) 93 0.91 (0.44, 1.88) 1.30 (0.74, 2.31)
Smoker
<0.0001
No/Unknown 1461 (71) 236 (56) 1697 Reference N/A Reference NA
Former 481 (23) 161 (38) 642 1.75 (1.51, 2.04) 1.14 (0.98, 1.33)
Current 128 (6) 22 (5) 150 1.06 (0.75, 1.49) 1.22 (0.99, 1.51)
Hypertension <0.0001
No 955 (46) 105 (25) 1060 Reference N/A Reference NA
Yes 1114 (54) 314 (75) 1428 2.18 (1.66, 2.86) 1.07 (0.79, 1.45)
Obesity
(BMI≥30)
0.001
No 944 (49) 224 (58) 1168 Reference N/A Reference N/A
Yes 992 (51) 162 (42) 1154 0.73 (0.61, 0.86) 1.09 (0.92, 1.30)
Diabetes <0.0001
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14
No 1423 (69) 244 (58) 1667 Reference N/A Reference N/A
Yes 644 (31) 175 (42) 819 1.44 (1.2, 1.72) 1.19 (1.01, 1.40
Chronic Lung
Disease
<0.0001
No 1489 (72) 248 (59) 1737 Reference N/A Reference N/A
Yes 577 (28) 170 (41) 747 1.56 (1.27, 1.91) 1.31 (1.13, 1.52)
Cardiovascular
Disease
<0.0001
No 1462 (71) 165 (39) 1627 Reference N/A Reference N/A
Yes 605 (29) 254 (61) 859 2.85 (2.42, 3.36) 1.28 (1.03, 1.58)
Neurologic <0.0001
No 1674 (81) 262 (63) 1936 Reference N/A Reference N/A
Yes 391 (19) 157 (37) 548 2.10 (1.72, 2.56) 1.25 (1.04, 1.50)
Renal
<0.0001
No 1814 (88) 288 (69) 2102 Reference N/A Reference N/A
Yes 255 (12) 131 (31) 386 2.45 (2.04, 2.93) 1.33 (1.10, 1.61)
Immuno-
suppression
<0.0001
No 1873 (91) 351 (84) 2224 Reference N/A Reference N/A
Yes 195 (9) 68 (16) 263 1.58 (1.33, 1.88) 1.39 (1.13, 1.70)
Gastro-
intestinal
or Liver
0.12
No 1975 (96) 393 (94) 2368 Reference N/A N/A N/A
Yes 92 (4) 26 (6) 118 1.30 (1.00, 1.70) N/A N/A
Hematologic
0.02
No 2005 (97) 398 (95) 2403 Reference N/A Reference N/A
Yes 59 (3) 21 (5) 80 1.54 (1.11, 2.12) 1.33 (0.93, 1.9)
Rheumatologic
or Autoimmune
0.03
No 2010 (97) 399 (95) 2409 Reference N/A Reference N/A
Yes 57 (3) 20 (5) 77 1.53 (1.03, 2.29) 0.87 (0.66, 1.16)
Outpatient ACE-
Inhibitor Use
0.99
No/Unknown 1312 (83) 264 (83) 1576 Reference N/A N/A N/A
Yes 263 (17) 53 (17) 316 0.98 (0.74, 1.30) N/A N/A
Outpatient
Angiotensin
0.11
No/Unknown 1372 (87) 266 (84) 1638 Reference N/A N/A N/A
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15
Receptor
Blocker Use Yes 205 (13) 52 (16) 257 1.19 (0.91, 1.57) N/A N/A
CI = confidence interval; N/A = not applicable; ACE = angiotensin-converting-enzyme
*Final model adjusted for age, sex, race/ethnicity, smoker, hypertension, obesity, diabetes, chronic lung disease, cardiovascular disease, neurologic disease, renal disease,
immunosuppression, hematologic disorders, and rheumatologic or autoimmune disease.
for use under a CC0 license.
This article is a US Government work. It is not subject to copyright under 17 USC 105 and is also made available
(which was not certified by peer review) is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity.
The copyright holder for this preprintthis version posted May 22, 2020. ; https://doi.org/10.1101/2020.05.18.20103390doi: medRxiv preprint
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