Table 2.
Factors Associated with High SARS-CoV-2 Viral Load (cobas SARS-CoV-2 Assay, CT < 25; Xpert Xpress SARS-CoV-2 Assay, CT < 27) on Admission
| Variable | Univariate Model: Unadjusted OR (95% CI) | p Value | Multivariate Model: Adjusted OR (95% CI) | p Value |
|---|---|---|---|---|
| Cancer Status | ||||
| No active cancer | Reference | Reference | ||
| Solid tumor | 1.21 (0.71–2.06) | 0.49 | 0.96 (0.54–1.69) | 0.88 |
| Hematologic malignancy | 2.48 (1.33–4.63) | 0.004 | 2.52 (1.30–4.88)b | 0.006 |
| Demographics | ||||
| Age, per year increase | 1.03 (1.02–1.03) | <0.001 | 1.02 (1.02–1.03) | <0.001 |
| Female | 1.03 (0.88–1.21) | 0.67 | ||
| Race/ethnicity | ||||
| White (non-Hispanic) | Reference | Reference | ||
| Black (non-Hispanic) | 0.71 (0.53–0.95) | 0.019 | 0.76 (0.56–1.04) | 0.09 |
| Asian (non-Hispanic) | 1.04 (0.83–1.30) | 0.74 | 1.17 (0.91–1.49) | 0.23 |
| Hispanic | 0.49 (0.40–0.61) | <0.001 | 0.70 (0.56–0.89) | 0.004 |
| Other or missing | 0.64 (0.48–0.84) | 0.002 | 0.88 (0.65–1.19) | 0.41 |
| Comorbidities | ||||
| Obesity (BMI > 30: n = 2,832)a | 0.79 (0.66–0.94) | 0.007 | ||
| Coronary artery diseasea | 1.71 (1.39–2.10) | <0.001 | ||
| Congestive heart failure | 2.39 (1.79–3.21) | <0.001 | 1.46 (1.06–2.00) | 0.019 |
| Diabetes mellitus | 1.64 (1.40–1.93) | <0.001 | 1.68 (1.32–2.14) | <0.001 |
| Hypertension | 1.54 (1.32–1.79) | <0.001 | 0.78 (0.61–0.99) | 0.042 |
| Chronic pulmonary diseasea | 1.53 (1.25–1.87) | <0.001 | ||
| Chronic kidney disease | 2.41 (1.88–3.09) | <0.001 | 2.00 (1.53–2.62) | <0.001 |
| Cirrhosis | 0.73 (0.31–1.73) | 0.48 | ||
| HIV infection | 0.88 (0.39–2.01) | 0.76 | ||
| Solid organ transplanta | 1.90 (0.99–3.07) | 0.052 | ||
| Inflammatory bowel disease | 2.21 (0.55–8.85) | 0.26 | ||
| Rheumatic disease | 1.16 (0.76–1.78) | 0.50 | ||
| Home medications | ||||
| Inhaled or nasal steroid | 1.89 (1.35–2.66) | <0.001 | 1.64 (1.14–2.36) | 0.007 |
| Oral steroid | 1.86 (1.25–2.76) | 0.002 | 1.62 (1.06–2.48) | 0.025 |
| Calcineurin inhibitora | 1.85 (1.02–3.37) | 0.043 | ||
| Mycophenolatea | 1.96 (1.10–3.50) | 0.022 | ||
| Social Characteristics | ||||
| Active smoker | 1.16 (0.75–1.81) | 0.50 | ||
| Former smokera | 1.34 (1.10–1.63) | 0.004 | ||
| Recent international travel | 0.91 (0.37–2.19) | 0.83 | ||
| Known exposure to COVID-positive patient | 0.99 (0.79–1.23) | 0.91 | ||
| Healthcare worker | 0.91 (0.55–1.51) | 0.72 | ||
| Undomiciled | 1.30 (0.71–2.37) | 0.40 | ||
| Nursing home/rehabilitation facility resident | 2.06 (1.66–2.55) | <0.001 | 1.47 (1.15–1.87) | 0.002 |
| Duration of symptoms before admission, per dayb | 1.00 (1.00–1.00) | 0.57 | ||
| ED Presentation | ||||
| Relationship to apex of COVID-19 in New York City | ||||
| Pre-apex (March 15–29) | 1.25 (1.03–1.52) | 0.025 | 1.60 (1.28–1.99) | <0.001 |
| Apex (March 30–April 8) | Reference | Reference | ||
| Post-apex (April 9–May 14) | 0.92 (0.77–1.10) | 0.38 | 0.76 (0.63–0.92) | 0.006 |
| Hospital | ||||
| NYP/Queens | Reference | Reference | ||
| NYP/WCMC | 1.09 (0.91–1.31) | 0.33 | 1.27 (1.02–1.59) | 0.035 |
| NYP/LMH | 1.81 (1.45–2.25) | <0.001 | 1.67 (1.30–2.13) | <0.001 |
| cobas SARS-CoV-2 assay (versus Xpert Xpress assay)a | 1.23 (1.05–1.44) | <0.001 | ||
High viral load is designated as having a CT value < 25 using the cobas SARS-CoV-2-specific gene target (ORF1ab) and a CT value < 27 using the Xpert Xpress SARS-CoV-2 assay-specific gene target (N2). The different definitions were derived from published data that indicate CT values for the Xpert Xpress assay (N2 gene) are approximately two cycles greater than CT values for the cobas assay (ORF1ab gene; Smithgall et al., 2020). Bolded p values indicate those that meet statistical significance.
Abbreviations: BMI, body mass index; CI, confidence interval; ED, emergency department; HIV, human immunodeficiency virus; LMH, Lower Manhattan Hospital; NYP, NewYork-Presbyterian; OR, odds ratio; WCMC, Weill Cornell Medical Center.
Removed from final multivariate model because p value > 0.1 in multivariate analysis.
In a sensitivity analysis that added duration of symptoms to the multivariate model, having a hematologic malignancy was still independently associated with a high admission viral load (aOR = 2.37; 95% CI, 1.13–4.99; p = 0.023) compared with not having cancer (Table S1). See Table S2 for this analysis using the cobas viral load cutoffs for both the cobas and Xpert Xpress assays.