Table 2.
Comparison of COVID-19 infection, COVID-19 infection requiring hospitalization, and COVID-19 infection requiring intensive care unit admission among adults with and without prior exposure to children, unadjusted and propensity-matched
| Unadjusted | Propensity matched | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Study population | Comparator Groups | Comparison 1 | Comparison 2 | Comparison 3 | |||||||||
| Adults with children 0–5 y | Adults with children 6–11 y | Adults with children 12–18 y | Adults without children | Adults with children 0–5 y | Adults with children 6–11 y | P | Adults with children 0–5 y | Adults with children 12–18 y | P | Adults with children 0–5 y | Adults without children | P | |
| (n = 274,316) | (n = 211,736) | (n = 257,762) | (N = 2,382,613) | (n = 136,107) | (n = 136,107) | (n = 81,978) | (n = 81,978) | (n = 260,180) | (n = 260,180) | ||||
| COVID-19 infection | |||||||||||||
| Events | 15,057 | 11,444 | 14,114 | 94,172 | 7,467 | 8,111 | 4,843 | 5,285 | 14,444 | 12,244 | |||
| IR (per 100-PYs) | 5.49 | 5.40 | 5.48 | 3.95 | 5.49 | 5.96 | 5.91 | 6.45 | 5.55 | 4.71 | |||
| IRR | – | 0.98 | 1.00 | 0.72 | – | 1.09 | <0.0001 | – | 1.09 | <0.0001 | – | 0.85 | <0.0001 |
| 95% CI | – | [0.96–1.01] | [0.97–1.02] | [0.71–0.73] | – | [1.05–1.12] | – | [1.05–1.13] | – | [0.83–0.87] | |||
| Severe COVID outcomes estimated as population rates* | |||||||||||||
| COVID-19 infection requiring hospitalization | |||||||||||||
| Events | 341 | 459 | 679 | 10,521 | 225 | 262 | 172 | 180 | 327 | 414 | |||
| IR (per 100-PYs) | 0.12 | 0.22 | 0.26 | 0.44 | 0.17 | 0.19 | 0.21 | 0.22 | 0.13 | 0.16 | |||
| IRR | – | 1.74 | 2.12 | 3.55 | – | 1.16 | 0.09 | – | 1.05 | 0.70 | – | 1.27 | 0.0014 |
| 95% CI | – | [1.52–2.01] | [1.86–2.41] | [3.19–3.96] | – | [0.97–1.39] | – | [0.85–1.29] | – | [1.1–1.46] | |||
| COVID-19 infection requiring ICU | |||||||||||||
| Events | 44 | 69 | 118 | 1860 | 36 | 32 | 28 | 25 | 43 | 64 | |||
| IR (per 100-PYs) | 0.016 | 0.033 | 0.046 | 0.078 | 0.026 | 0.024 | 0.034 | 0.030 | 0.017 | 0.025 | |||
| IRR | – | 2.03 | 2.85 | 4.87 | – | 0.89 | 0.63 | – | 0.89 | 0.68 | – | 1.49 | 0.0437 |
| 95% CI | – | [1.39–2.97] | [2.02–4.03] | [3.61–6.56] | – | [0.55–1.43] | – | [0.52–1.53] | – | [1.01–2.19] | |||
| Severe COVID outcomes estimated as a proportion of COVID-19 infection cases† | |||||||||||||
| COVID-19 infection requiring hospitalization | |||||||||||||
| Events | 341 | 459 | 679 | 10,521 | 225 | 262 | 172 | 180 | 327 | 414 | |||
| IR (per 100-PYs) | 2.26 | 4.01 | 4.81 | 11.17 | 3.01 | 3.23 | 3.55 | 3.41 | 2.26 | 3.38 | |||
| IRR | – | 1.77 | 2.12 | 4.93 | – | 1.07 | 0.44 | – | 0.96 | 0.69 | – | 1.49 | <0.0001 |
| 95% CI | – | [1.54–2.04] | [1.87–2.42] | [4.43–5.49] | – | [0.90–1.28] | – | [0.78–1.18] | – | [1.29–1.73] | |||
| COVID-19 infection requiring ICU | |||||||||||||
| Events | 44 | 69 | 118 | 1860 | 36 | 32 | 28 | 25 | 43 | 64 | |||
| IR (per 100-PYs) | 0.29 | 0.60 | 0.84 | 1.98 | 0.48 | 0.39 | 0.58 | 0.47 | 0.30 | 0.52 | |||
| IRR | – | 2.06 | 2.86 | 6.76 | – | 0.82 | 0.41 | – | 0.82 | 0.47 | – | 1.76 | 0.0043 |
| 95% CI | – | [1.41–3.01] | [2.02–4.04] | [5.01–9.11] | – | [0.51–1.32] | – | [0.48–1.40] | – | [1.19–2.58] | |||
*Denominators for incidence rates (IR) and incidence rate ratios (IRR) are based upon total person years of study subgroup. PY = person-years. CI = confidence interval.
†Denominators for incidence rates (IR) and incidence rate ratios (IRR) are based upon the number of COVID-19 infection cases in the study subgroup.