Table 2.
Cross-sectional comparison of symptoms, clinical and laboratory findings, and neurocognitive test results among COVID-19 cases and non-COVID controls for participants with and without post-COVID-19 Condition (PCC) at 6 months follow-up.
| Reported symptoms | COVID-19 cases | Non-COVID controls | |||
|---|---|---|---|---|---|
| COVID + PCC+ | COVID + PCC- | COVID-PCC+ | COVID-PCC- | p-valuea | |
| Symptoms suggesting neurocognitive aberrations | |||||
| Concentration difficulty, score-mean (SD) | 3.3 (1.2) | 1.9 (1.1) | 3.3(1.1) | 2.1 (1.0) | <0.001 |
| Confidence interval | 3.2–3.5 | 1.7–2.0 | 2.9–3.6 | 1.8–2.4 | |
| Difficulty making decisions, score-mean (SD) | 2.7 (1.3) | 1.6 (0.9) | 2.3 (1.1) | 1.6 (0.9) | <0.001 |
| Confidence interval | 2.5–2.8 | 1.4–1.7 | 2.0–2.7 | 1.3–1.9 | |
| Memory difficulty, score-mean (SD) | 2.9 (1.3) | 1.7 (1.0) | 2.6 (1.3) | 1.8 (1.2) | <0.001 |
| Confidence interval | 2.7–3.1 | 1.6–1.8 | 1.2–3.0 | 1.4–2.1 | |
| Feeling confused or disoriented, score-mean (SD) | 1.8 (1.1) | 1.2 (0.6) | 1.5 (0.7) | 1.2 (0.7) | <0.001 |
| Confidence interval | 1.7–2.0 | 1.1–1.3 | 1.3–1.8 | 1.0–1.5 | |
| Sleep | |||||
| Karolinska sleep questionnaire, total score-mean (SD) | 40.7 (11.1) | 55.0 (10.4) | 42.8 (8.2) | 51.4 (10.0) | <0.001 |
| Confidence interval | 39.1–42.3 | 53.5–56.5 | 40.1–45.4 | 48.4–54.4 | |
| Insomnia subscore, −mean (SD) | 14.6 (4.5) | 18.7 (3.9) | 15.1 (4.0) | 17.7 (4.0) | <0.001 |
| Confidence interval | 14.0–15.3 | 18.2–19.3 | 13.8–16.4 | 16.5–18.9 | |
| Awakening problems subscore-mean (SD) | 8.9 (3.7) | 13.3 (3.6) | 9.3 (3.0) | 12.2 (3.2) | <0.001 |
| Confidence interval | 8.3–9.4 | 12.8–13.8 | 8.3–10.3 | 11.3–13.1 | |
| Sleepiness subscore, −mean (SD) | 14.2 (3.8) | 18.8 (3.6) | 15.1 (3.0) | 17.6 (3.6) | <0.001 |
| Confidence interval | 13.6–14.8 | 18.2–19.3 | 14.2–16.1 | 16.5–18.7 | |
| Pain | |||||
| Headache, score-mean (SD) | 2.6 (1.0) | 1.6 (0.8) | 2.3 (1.0) | 2.0 (0.9) | <0.001 |
| Confidence interval | 2.4–2.7 | 1.5–1.8 | 2.0–2.6 | 1.7–2.3 | |
| Brief pain inventory total score, mean (SD) | 11.5 (5.5) | 7.7(3.8) | 11.7(4.5) | 9.7(4.5) | <0.001 |
| Confidence interval | 10.8–12.4 | 7.2–8.3 | 10.3–13.1 | 8.4–11.1 | |
| Worst pain in 24 h, mean (SD) | 4.4 (2.3) | 3.0 (2.1) | 5.2 (2.3) | 4.0 (2.3) | <0.001 |
| Confidence interval | 4.1–4.8 | 2.7–3.2 | 4.5–5.9 | 3.4–4.7 | |
| Least pain in 24 h, mean (SD) | 1.9 (1.5) | 1.4 (1.1) | 1.4 (0.7) | 1.8 (1.8) | <0.001 |
| Confidence interval | 1.7–2.1 | 1.3–1.6 | 1.2–1.6 | 1.2–2.3 | |
| Pain on average, mean (SD) | 3.2 (1.8) | 1.9 (1.2) | 3.0 (1.4) | 2.5 (2.0) | <0.001 |
| Confidence interval | 2.9–3.4 | 1.8–2.1 | 2.6–3.5 | 1.9–3.1 | |
| Pain right now, mean (SD) | 2.1 (1.6) | 1.4 (1.2) | 2.1 (1.3) | 1.4 (0.6) | <0.001 |
| Confidence interval | 1.9–2.3 | 1.2–1.6 | 1.7–2.5 | 1.2–1.5 | |
| Neurological findings and brain injury biomarkers | |||||
| Neurological examination, any findings -No. (%) | 5 (2.7%) | 8 (4%) | 2(5%) | 3(6.7%) | 0.625 |
| Neurofilament light chain, pg./mL, median (iqr) | 4.5 (1.9) | 4.9 (2.5) | 4.4 (1.9) | 4.6 (1.9) | 0.156b |
| Confidence interval | 4.2–4.8 | 4.6–5.1 | 4.1–5.0 | 4.4–5.1 | |
| Glial fibrillary acidic protein, pg./mL, median (iqr) | 64.9 (30.3) | 65.8 (40.4) | 62.2 (30.4) | 71.8 (35.9) | 0.607b |
| Confidence interval | 60.2–68.8 | 61.1–72.8 | 57.9–77.7 | 59.8–86.7 | |
| Neurocognitive test results | |||||
| Digit span forward, total sum score -mean (SD) | 10.0 (2.5) | 9.9 (2.5) | 9.7 (2.2) | 9.3 (2.4) | 0.344 |
| Confidence interval | 9.6–10.4 | 9.6–10.3 | 9.0–10.4 | 8.6–10.0 | |
| Digit span backward, total sum score -mean (SD) | 6.0 (2.4) | 6.1 (2.2) | 6.0 (3.1) | 5.6 (1.8) | 0.670 |
| Confidence interval | 5.7–6.4 | 5.7–6.4 | 5.0–6.9 | 5.0–6.1 | |
| Digit span summary score, −mean (SD) | 16.0 (4.3) | 16.0 (4.0) | 16.0 (4.0) | 14.8 (3.8) | 0.368 |
| Confidence interval | 15.4–16.6 | 15.4–16.5 | 14.2–17.2 | 13.7–16.0 | |
| HVLT-R immediate recall, total sum score -mean (SD) | 23.4 (4.8) | 23.9 (4.4) | 22.9 (5.2) | 23.0 (4.6) | 0.401 |
| Confidence interval | 22.7–24.1 | 23.3–24.5 | 21.2–24.6 | 21.6–24.3 | |
| HVLT-R delayed recall, total sum score -mean (SD) | 8.3 (2.3) | 8.3 (2.2) | 7.9 (2.5) | 7.9 (2.5) | 0.521 |
| Confidence interval | 8.0–8.7 | 8.0–8.6 | 7.1–8.7 | 7.2–8.7 | |
| HVLT-R correct recognition, mean (SD) | 11.4 (1.1) | 11.4 (0.9) | 11.4 (0.8) | 11.4 (1.0) | 0.941 |
| Confidence interval | 11.3–11.6 | 11.3–11.6 | 11.3–11.6 | 11.1–11.7 | |
| HVLT-R false recognition, mean (SD) | 0.3 (0.7) | 0.3 (0.6) | 0.4 (0.7) | 0.5 (0.9) | 0.349 |
| Confidence interval | 0.2–0.4 | 0.2–0.4 | 0.1–0.6 | 0.2–0.8 | |
aOne-way ANOVA unless otherwise stated. bKruskal-Wallis.