Table 1.
Demographic Characteristics, Comorbidities, and Time to SARS-CoV-2 PCR Clearance in Patients Followed at Boston Medical Center for SARS-CoV-2 Infection and Retested Within 90 Days, March 2020–February 2021
| Characteristic | No. (%) (n = 3758) | Median (IQR) Time to First Negative PCR,a d | Unadjusted Hazard Ratio (95% CI)b | Adjusted Hazard Ratio (95% CI)b | Adjusted Hazard Ratio (95% CI)b |
|---|---|---|---|---|---|
| Age, mean (SD, range), y | 48.8 (16.4, 18–99) | — | 0.995 (0.992–0.997) | 0.997 (0.994–1.000) | 0.996 (0.993–0.999) |
| Age quartiles, y | |||||
| 18–35 | 947 (25.2) | 13 (4–28) | Ref. | — | — |
| 36–48 | 937 (24.9) | 16 (5–26) | 0.94 (0.83–1.05) | — | — |
| 49–60 | 933 (24.8) | 17 (8–30) | 0.87 (0.78–0.98) | — | — |
| >60 | 941 (25.0) | 21 (6–33) | 0.81 (0.72–0.90) | — | — |
| Sex | |||||
| Male | 1677 (44.6) | 18 (6–31) | 0.97 (0.89–1.05) | — | — |
| Female | 2081 (55.5) | 14 (7–29) | Ref. | — | — |
| Race/ethnicity | |||||
| Black, non-Hispanic | 1123 (29.9) | 14 (6–27) | 1.10 (1.00–1.21) | — | — |
| Hispanic or Latino | 1739 (46.3) | 18 (6–31) | Ref. | — | — |
| White, non-Hispanic | 509 (13.5) | 18 (6–33) | 0.95 (0.84–1.08) | — | — |
| Other race (non-Hispanic) | 128 (3.4) | 17 (3–29) | 1.06 (0.84–1.34) | — | — |
| Unknown/declined | 259 (6.9) | 15 (7–27) | 1.08 (0.91–1.28) | — | — |
| COVID-19 severity | |||||
| Deceased | 91 (2.4) | 26 (11–33) | 0.67 (0.50–0.91) | 0.77 (0.56–1.04) | 0.76 (0.56–1.03) |
| ICU | 180 (4.8) | 21 (2–25) | 0.93 (0.77–1.12) | 1.01 (0.83–1.22) | 1.04 (0.86–1.27) |
| Hospitalized, no ICU | 664 (17.7) | 21 (7–32) | 0.84 (0.74–0.96) | 0.91 (0.80–1.04) | 0.92 (0.80–1.05) |
| Not hospitalized | 1012 (26.9) | 13 (7–27) | Ref. | Ref. | Ref. |
| Unknown | 1811 (48.2) | 16 (7–29) | 0.88 (0.79–0.97) | 0.86 (0.78–0.95) | 0.87 (0.79–0.96) |
| Immunocompromise categoryc | |||||
| Severe | 277 (7.4) | 22 (4–34) | 0.93 (0.80–1.08) | 0.98 (0.84–1.15) | — |
| Active chemotherapy | 212 (5.6) | 19 (1–34) | 0.98 (0.82–1.16) | — | — |
| High-dose steroids | 55 (1.5) | 23 (6–33) | 0.81 (0.59–1.12) | — | — |
| HIV with CD4 <200 | 10 (0.3) | 27 (8–27) | 0.72 (0.35–1.46) | — | — |
| Moderate | 159 (4.2) | 20 (8–33) | 0.82 (0.67–1.01) | 0.86 (0.70–1.05) | — |
| Solid organ transplantd | 43 (1.1) | 31 (14–47) | 0.60 (0.40–0.90) | — | 0.64 (0.42–0.97) |
| Chronic biologic | 23 (0.6) | 30 (10–33) | 0.78 (0.48–1.26) | — | — |
| HIV with CD4 >200 | 33 (0.9) | 15 (6–29) | 0.85 (0.56–1.29) | — | — |
| Othere | 60 (1.6) | 20 (8–27) | 1.08 (0.78–1.50) | — | — |
| Immunocompetent | 3322 (88.4) | 16 (6–29) | Ref. | Ref. | — |
| Comorbidities | |||||
| Diabetes | 642 (17.1) | 22 (9–36) | 0.77 (0.69–0.86) | — | 0.82 (0.73–0.93) |
| Coronary artery disease | 150 (4.0) | 21 (6–40) | 0.81 (0.66–1.01) | — | 0.94 (0.75–1.17) |
| Hypertension | 1120 (29.8) | 21 (9–33) | 0.90 (0.82–0.98) | — | 1.07 (0.96–1.20) |
| ESRD | 98 (2.6) | 21 (13–33) | 0.76 (0.59–1.00) | — | 0.97 (0.72–1.30) |
| Cirrhosis | 43 (1.1) | 24 (1–30) | 0.83 (0.57–1.20) | — | — |
| Obesity | 1758 (46.8) | 19 (7–31) | 0.89 (0.82–0.96) | — | 0.90 (0.83–0.98) |
| Chronic lung disease | 413 (11.0) | 21 (9–34) | 0.91 (0.80–1.04) | — | 0.94 (0.82–1.07) |
| Rheumatologic disease | 85 (2.3) | 24 (1–36) | 0.72 (0.55–0.94) | — | 0.75 (0.57–0.98) |
| None of the above | 2166 (57.6) | 15 (6–28) | Ref. | Ref. | — |
| ≥1 of the above | 876 (23.3) | 16 (6–29) | 0.92 (0.83–1.02) | 0.96 (0.86–1.06) | — |
| ≥2 of the above | 507 (13.5) | 20 (9–30) | 0.84 (0.74–0.95) | 0.89 (0.77–1.02) | — |
| ≥3 of the above | 209 (5.6) | 24 (10–36) | 0.68 (0.57–0.82) | 0.73 (0.60–0.88) | — |
| Other conditions (in the absence of other immunocompromising conditions) | |||||
| Acute IL-6 or IL-1 inhibitorf | 154 (4.1) | 24 (11–30) | 0.87 (0.72–1.06) | — | — |
| Acute corticosteroidf | 328 (8.7) | 17 (7–32.5) | 0.95 (0.82–1.10) | — | — |
| B-cell function deficiencyg | 5 (0.1) | 32.5 (18–47.5) | 0.60 (0.22–1.60) | — | — |
| Pregnant | 203 (5.4) | 14 (8–32) | 0.90 (0.74–1.08) | — | — |
Boldface indicates P value <.05.
Abbreviations: COVID-19, coronavirus disease 2019; ESRD, end-stage renal disease; ICD-10, International Classification of Diseases, 10th edition; ICU, intensive care unit; IL, interleukin; IQR, interquartile range; PCR, polymerase chain reaction; SARS-CoV-2, severe acute respiratory syndrome coronavirus 2.
aNonparametric survival analysis accounting for interval-censored data utilizing the Expectation–Maximization-Iterative Convex Minorant algorithm to impute median survival estimates and standard errors.
bHazard ratios for time to SARS-CoV-2 PCR clearance obtained using Cox proportional hazards regression accounting for interval-censored data, unadjusted and adjusted for (1) age, disease severity, immunocompromise category, and variables with P < .2 in the univariate analysis and (2) age, disease severity, and individual variables with P < .2 in the univariate analysis.
cImmunocompromise categories are mutually exclusive—if individuals met multiple categories, they were categorized as the most severe (first listed) category.
dSolid organ transplant is considered moderate rather than severe, as all chart-reviewed patients in this category had their transplant >1 year before COVID-19 diagnosis.
eOther immunocompromise includes: rheumatologic conditions, myelofibrosis, asplenia, chronic neutropenia, and other blood and immune disorders (identified by ICD-10 codes on the problem list); immunocompromising medications not included in active chemotherapy category: hydroxyurea, methotrexate, azathioprine.
fFor COVID-19 treatment; only includes individuals not otherwise categorized as immunocompromised.
gOn chronic medication that suppresses B-cell function directly or indirectly (rituximab, belimumab, natalizumab, or daratumumab) in the absence of concurrent cytotoxic chemotherapy.