Table 1.
General characteristics of the study population and risk factors associated with COVID-19 emergency department return
| Total population [n = 109] |
ED return due to COVID-19 [n = 21] n (%) |
ED no return [n = 84] n (%) |
OR (95%CI) | P value | |
|---|---|---|---|---|---|
| Demographics | |||||
| Age, years | 50 (40—59.5) | 52.0 (40.0–62.0) | 51.2 (42.0–58.2) | ||
| < 65 | 93 (85.3) | 18 (85.7) | 75 (89.2) | 1 (ref) | |
| ≥ 65 | 16 (14.7) | 3 (14.3) | 9 (10.7) | 0.96 (0.25–3.73) | .955 |
| Gender, % | |||||
| Male | 56 (52.3) | 8 (38.1) | 49 (58.3) | 1(ref) | |
| Female | 53(47.7) | 13 (61.9) | 35 (41.7) | 2.04 (0.77–5.42) | .152 |
| Long-term care resident | 0.9 | 0.0 | |||
| No | 108 (99.1) | 21(100) | 84 (100) | 1(ref) | |
| Yes | 1 (0.01) | 0(0.0) | 0 (0.0) | NC | - |
| Health professional % | |||||
| No | 91 (83.5) | 14 (66.7) | 74 (88.1) | 1(ref) | |
| Yes | 18 (16.5) | 7 (21.1) | 10 (11.9) | 3.50 (1.16–10.57) | .026 |
| Comorbidities | |||||
| Hypertension | |||||
| No | 89 (81.7) | 10 (47.6) | 56 (66.7) | 1(ref) | |
| Yes | 20 (18.3) | 3 (14.3) | 28 (33.3) | 0.69 (0.18–2.64) | .594 |
| Type 2 diabetes | |||||
| No | 100 (91.7) | 17 (81) | 83 (98.8) | 1(ref) | |
| Yes | 9 (8.3) | 4 (19.0) | 1 (1.2) | 3.91 (0.95–16.07) | .059 |
| Body mass index, kg/m2 | 26.4 (22.9–29.3) | 26.3 (24.5–30.4) | 25.2 (24.6–29.6) | ||
| Obesity | |||||
| No | 83 (76.1) | 15 (71.4) | 68 (80.1) | 1(ref) | |
| Yes | 26 (23.9) | 6 (28.6) | 16 (19.0) | 1.36 (0.47–3.96) | .573 |
| Cardiovascular disease | |||||
| No | 100 (91.7) | 18 (85.7) | 82 (97.6) | 1(ref) | |
| Yes | 9 (8.3) | 3 (14.2) | 2 (2.4) | 2.22 (0.51–9.74) | .289 |
| Smoke | |||||
| No | 94 (86.2) | 18 (85.7) | 76 (90.5) | 1(ref) | |
| Yes | 15 (13.9) | 3 (14.2) | 8 (9.5) | 1.04 (026–4.08) | .953 |
| Chronic respiratory disease | |||||
| No | 90 (82.6) | 18 (85.7) | 72 (85.7) | 1(ref) | |
| Yes | 19 (17.4) | 3 (14.3) | 12 (14.3) | 0.73 (0.19–2.78) | .643 |
| Immunosuppression | |||||
| No | 104 (95.4) | 19 (90.5) | 81 (96.4) | 1(ref) | |
| Yes | 5 (4.6) | 2 (9.5) | 3 (3.6)) | 2.98 (0.46–19.10) | .249 |
| Charlson comorbidity index | 1.0 (0.0–2.0) | 1.0 (0.0–2.0) | 1.0 (0.0–2.0) | ||
| Charlson index ≥ 1 | |||||
| No | 46 (42.2) | 6 (28.6) | 40 (47.6) | 1(ref) | |
| Yes | 63 (57.8) | 15 (71.4) | 44 (52.4) | 2.08 (0.74–5.87) | .165 |
| 10-year expected survival, %a | 95.8 (77.4–98.3) | 95.8 (83.7–98.1) | 94.6 (84.5 – 99.1) | ||
| > 96 | 40 (36.7) | 6 (28.6) | 34 (40.5) | 1(ref) | |
| < 96 | 66 (60.6) | 12 (57.1) | 50 (59.5) | 1.26 (0.43–3.67) | .673 |
| Clinical presentation | |||||
| Clinical duration, daysb | 7.00 (4.0–10.0) | 6.5 (3.2–9.5) | 7.8 (3.5 – 9.6) | ||
| > 7 | 60 (55.0) | 10 (47.6) | 50 (59.5) | ||
| < 7 | 48 (44.0) | 11 (52.4) | 34 (40.4) | 1.32 (0.49–3.48) | .580 |
| Fever (temperature > 37.8 ºC) | |||||
| No | 39 (35.8) | 10 (47.6) | 29 (34.5) | 1(ref) | |
| Yes | 70 (64.2) | 11 (52.3) | 55 (65.4) | 0.54 (0.21–1.42) | .212 |
| Dry cough | |||||
| No | 39 (35.8) | 8 (38.1) | 31 (36.9) | 1 (ref) | |
| Yes | 69 (63.9) | 13 (11.9) | 53 (63.1) | 0.90 (0.34–2.41) | .833 |
| Wet cough | |||||
| No | 92 (84.4) | 18 (85.7) | 74 (88) | 1 (ref) | |
| Yes | 17 (15.6) | 3 (14.3) | 10 (11.9) | 0.88 (0.23–3.39) | .854 |
| Dyspnea | |||||
| No | 64 (58.7) | 10 (47.6) | 54 (64.3) | 1 (ref) | |
| Yes | 45 (41.3) | 11 (52.4) | 30 (35.7) | 1.75 (0.67–4.55) | .254 |
| Diarrhea | |||||
| No | 87 (79.8) | 18 (85.7) | 69 (82.1) | 1 (ref) | |
| Yes | 22 (20.2) | 3 (14.2) | 15 (17.8) | 0.61 (0.16–2.27) | .457 |
| Confusion | |||||
| No | 109 (100) | 21 (100) | 84 (100) | 1 (ref) | |
| Yes | 0 (0.0) | 0 (0.0) | 0 (0.0) | NC | - |
| Fatigue | |||||
| No | 80 (73.3) | 16 (76.2) | 64 (76.1) | 1 (ref) | |
| Yes | 29 (26.6) | 5 (23.8) | 20 (23.8) | 0.83 (0.27–2.52) | .747 |
| Myalgias-arthralgias | |||||
| No | 60 (55) | 14 (66.7) | 46 (54.7) | 1 (ref) | |
| Yes | 49 (44.9) | 7 (33.3) | 38 (45.2) | 0.55 (0.20–1.48) | .237 |
| Anosmia-dysgeusia | |||||
| No | 92 (84.4) | 12 (57.1) | 80 (95.2) | 1 (ref) | |
| Yes | 17 (15.6) | 2 (9.5) | 4 (4.8) | 0.51 (0.11–2.43) | .401 |
| Initial assessment | |||||
| Room air oximetry, % | 97.0 (96.0–99.0) | 97.0 (95.5–99.5) | 98.0 (95.8 – 99.6) | ||
| > 97% | 48 (44.0) | 9 (42.8) | 39 (46.4) | 1 (ref) | |
| < 97% | 61 (55.9) | 12 (57.1) | 45 (53.6) | 1.06 (0.41–2.77) | .904 |
| PaO2/FiO2 | 448.0 (390.0–471.0) | 454.9 (397.5–478.4) | 458.9 (392.4 – 478.5) | ||
| > 448 | 73 (67) | 7 (33.3) | 66 (78.6) | 1 (ref) | |
| < 448 | 36 (33.0) | 5 (23.8) | 18 (21.4) | 0.62 (0.12–3.19) | .575 |
| Respiratory rate, breaths/min | 14.0 (12.0–16.0) | 15.0 (13.0–16.0) | 14.5 (12.4 – 15.3) | ||
| < 14 | 44 (40.4) | 5 (23.8) | 38 (45.2) | 1 (ref) | |
| > 14 | 65 (59.6) | 16 (76.2) | 46 (54.8) | 2.48 (0.83–7.38) | .102 |
| Systolic BP, mmHg | 137.5 (124.0–151.0) | 137.0 (122.0–141.5) | 132.3 (123.4 – 138.7) | ||
| > 137 | 55 (50.5) | 10 (47.6) | 45 (53.6) | 1 (ref) | |
| < 137 | 54 (49.5) | 11 (52.3) | 39 (46.4) | 1.10 (0.42–2.85) | .845 |
| Diastolic BP, mmHg | 87.0 (75.0–98.0) | 80.0 (71.5–84.5) | 78.2 (71.3 – 82.2) | ||
| > 87 | 51 (46.7) | 3 (14.2) | 48 (57.1) | 1 (ref) | |
| < 87 | 56 (51.3) | 18 (85.7) | 36 (42.9) | 7.57 (2.07–27.65) | .002 |
| Heart rate, bpm | 95 (86.0–103.0) | 90.0 (81.5–99.5) | 83 (81.2 – 102. 5) | ||
| > 95 | 52 (47.7) | 6 (28.6) | 46 (54.8) | 1 (ref) | |
| < 95 | 57 (52.2) | 15 (71.4) | 38 (45.2) | 1.79 (0.62–5.19) | .278 |
| Laboratory data | |||||
| eGFR, ml/min/m2 | 90.0 (83.6–90.0) | 90.0 (79.0–90.0) | 90.0 (82.4 – 90.09 | ||
| > 60 | 105 (96.3) | 19 (90.4) | 82 (97.6) | 1 (ref) | |
| < 60 | 4 (3.7) | 2 (9.5) | 2 (2.4) | 4.36 (0.57–33.01) | .153 |
| Creatine phosphokinase, U/L | 81.0 (55.0–121.0) | 82.0 (47.0–141.0) | 81.1 (60.2–140.4) | ||
| < 121 | 79 (72.4) | 14 (66.7) | 65 (77.4) | 1 (ref) | |
| > 121 | 28 (25.7) | 7 (33.3) | 19 (22.6) | 1.54 (0.55–4.34) | .407 |
| Troponin T, ng/L | 6.0 (5.0–7.0) | 5.5(5.0–12.5) | 5.2 (5.0 – 7.2) | ||
| < 7 | 77 (70.6) | 12 (4.8) | 65 (77.4) | 1 (ref) | |
| > 7 | 37 (33.9) | 8 (38.1) | 19 (22.6) | 1.26 (0.46–3.44) | .646 |
| Alanine aminotransferase, U/L | 21.0 (15.0–32.5) | 21.0 (13.0–36.5) | 16.6 (14.2 – 34.3) | ||
| < 30 | 78 (71.5) | 15 (71.4) | 53 (63) | 1 (ref) | |
| > 30 | 31 (28.4) | 6 (28.5) | 31 (36.9) | 1.01 (0.35–2.89) | .988 |
| Aspartate aminotransferase, U/L | 24.0 (19.0–30.0) | 24.0 (19.5–28.5) | 22 (19.8 – 27.4) | ||
| < 30 | 78 (71.6) | 17 (81) | 61 (72.6) | 1 (ref) | |
| > 30 | 31 (28.4) | 4 (19.0) | 23 (27.4) | 0.53 (0.16–1.72) | .294 |
| Brain natriuretic peptide, pg/mL | 36.5 (19.0–83.0) | 38.0 (23.0–64.2) | 35.2 (21.3 – 80.3) | ||
| < 83 | 75 (68.9) | 16 (76.2) | 59 (70.2) | 1 (ref) | |
| > 83 | 27 (24.8) | 4 (19.0) | 25 (29.8) | 0.64 (0.19–2.12) | .467 |
| C-reactive protein, mg/dL | 0.80 (0.19–3.16) | 0.5 (0.1–2.5) | 0.4 (0.2 – 0.8) | ||
| < 3 | 82 (75.2) | 17 (80.9) | 65 (77.4) | 1 (ref) | |
| > 3 | 27 (24.8) | 4 (19.0) | 19 (22.6) | 0.52 (0.11–2.53) | .420 |
| Procalcitonin, ng/mL | 0.040 (0.03–0.06) | 0.045 (0.03–0.07) | 0.04 (0.03 – 0.05) | ||
| < 0.06 | 36 (33.0) | 8 (38.1) | 28 (33.3) | 1 (ref) | |
| > 0.06 | 68 (62.3) | 12 (57.4) | 56 (66.7) | 0.75 (0.27–2.04) | .574 |
| Lactate dehydrogenase, U/L | 203.0 (172.0–232.0) | 201.0 (173.5–221.5) | 180.4 (173.4 -223.4) | ||
| < 232 | 79 (72.5) | 19 (90.5) | 60 (71.4) | 1 (ref) | |
| > 232 | 28 (25.7) | 2 (9.5) | 24 (28.6) | 0.24 (0.05–1.12) | .070 |
| D-dimers, ng/mL | 0.38 (0.23–0.61) | 0.34 (0.25–0.54) | 0.2 (0.1 – 0.5) | ||
| < 0.6 | 77 (70.1) | 17 (80.9) | 60 (71.4) | 1 (ref) | |
| > 0.6 | 28 (25.7) | 4 (19.0) | 24 (28.6) | 0.58 (0.17–1.92) | .381 |
| Leukocytes, per mm3 | 7000.0 (5505.0–8430.0) | 6460.0 (5040.0–8375.0) | 6890 (5038 – 7896.4) | ||
| < 8430 | 82 (75.2) | 17 (80.9) | 65 (77.4) | 1 (ref) | |
| > 8430 | 27 (24.8) | 4 (19.0) | 19 (22.6) | 0.66 (0.20–2.18) | .501 |
| Lymphocytes, per mm3 | 1750.0 (1210.0–2360.0) | 1500.0 (1075.0–1895.0) | 1345.2 (1080.2 -2320.4) | ||
| > 1210 | 82 (75.2) | 15 (71.4) | 67 (79.8) | 1 (ref) | |
| < 1210 | 27 (24.8) | 6 (28.6) | 17 (20.2) | 1.27 (0.44–3.71) | .654 |
| Ferritin, μg/L | 211.0 (106.2–456.7) | 220.5 (59.7–532.2) | 210.4 (140.5 -350.6 | ||
| < 450 | 32 (29.4) | 9 (42.9) | 23 (27.4) | 1 (ref) | |
| > 450 | 10 (9.2) | 3 (14.3) | 61 (72.6) | 1.09 (0.23–5.19) | .909 |
| Pneumonia features | |||||
| Bilateral pneumonia | |||||
| No | 40 (36.7) | 6 (28.5) | 34 (40.5) | 1 (ref) | |
| Yes | 69 (63.3) | 15 (71.4) | 50 (59.5) | 1.57 (0.55–4.45) | .392 |
| CURB65 score ≥ 1 | |||||
| No | 84 (77.1) | 16 (76.2) | 68 (80.9) | 1 (ref) | |
| Yes | 21 (19.3) | 5 (23.8) | 16 (19.0) | 1.32 (0.42–4.16) | .626 |
| Outpatient therapy | |||||
| Azithromycin | |||||
| No | 21 (19.3) | 5 (23.8) | 16 (19.0) | 1 (ref) | |
| Yes | 87 (79.8) | 16 (76.2) | 68 (80.9) | 0.72 (0.23–2.25) | .574 |
| Another antibiotic | |||||
| No | 74 (67.9) | 18 (85.7) | 56 (66.7) | ||
| Yes | 35 (32.1) | 3 (14.3) | 28 (33.3) | 0.28 (0.08–1.05) | .059 |
Data shown as median (p25-75), % (Risk Factor Present) unless otherwise specified; number of patients who returned / total number (%). “P” in bold, statistically significant differences. a10-year expected survival derived from Charlson comorbidity index score. bDays of symptoms before admission
Continuous covariates were categorized based on their median levels, except laboratory parameters that were categorized regarding their 75-percentiles, to show the impact of severe, extreme values in the outcomes – except for those in which severity is defined by lowest levels, such as lymphocyte counts, where 25-percentiles were used. For the following variables, standard categorizations were followed: age ≥ 65 years, Charlson comorbidity index ≥ 3, estimated glomerular filtration rate (eGFR, by CKD-EPI formula) < 60 ml/min/1.73 m2, and CURB65 ≥ 1
BP, blood pressure; CURB65, Severity Score for Community-Acquired Pneumonia; eGFR, estimated glomerular filtration rate (by CKD-EPI formula). Outpatient therapy also included hydroxychloroquine, amoxicillin, other antibiotics, without impact on return to emergency department (data not reported)