Table 1.
Demographic Characteristics and Medical History of Children Hospitalized with Respiratory Syncytial Virus (RSV) Bronchiolitis, by RSV Genomic Load Tertile
| Characteristic | RSV Genomic Load,a Children, No. (%) |
P Valueb | ||
|---|---|---|---|---|
| Low (n = 587) | Intermediate (n = 598) | High (n = 579) | ||
| Age, moc | <.001 | |||
| <2 | 165 (28) | 195 (33) | 208 (36) | |
| 2–5.9 | 225 (38) | 198 (33) | 231 (40) | |
| 6–11.9 | 115 (20) | 133 (22) | 85 (15) | |
| 12–23.9 | 82 (14) | 72 (12) | 55 (10) | |
| Male sex | 321 (55) | 341 (57) | 369 (64) | .005 |
| Race/ethnicity | <.001 | |||
| Non-Hispanic white | 201 (34) | 270 (45) | 301 (52) | |
| Non-Hispanic black | 123 (21) | 109 (18) | 110 (19) | |
| Hispanic | 238 (41) | 193 (32) | 142 (25) | |
| Other | 25 (4) | 26 (4) | 26 (5) | |
| Insurance | <.001 | |||
| Nonprivate | 443 (75) | 389 (65) | 381 (66) | |
| Private | 144 (25) | 209 (35) | 198 (34) | |
| Family history of asthma | .23 | |||
| Neither parent | 411 (70) | 396 (66) | 390 (67) | |
| Either mother or father | 143 (24) | 168 (28) | 163 (28) | |
| Both parents | 22 (4) | 25 (4) | 14 (2) | |
| Unknown/missing | 11 (2) | 9 (2) | 12 (2) | |
| Maternal smoking during pregnancy | 76 (13) | 93 (16) | 96 (17) | .19 |
| Gestational age, wk | ||||
| <32 | 29 (5) | 18 (3) | 20 (4) | |
| 32–36 | 83 (14) | 103 (17) | 95 (16) | |
| ≥37 or full term | 453 (77) | 465 (78) | 453 (78) | |
| Is or was breast-fed | 378 (64) | 386 (65) | 377 (65) | .98 |
| History of wheezing | 113 (19) | 105 (18) | 115 (20) | .58 |
| History of eczema | 94 (16) | 96 (16) | 71 (12) | .11 |
| History of intubation | 42 (7) | 44 (7) | 39 (7) | .91 |
| Major, relevant, comorbid medical disorderd | 87 (15) | 103 (17) | 88 (15) | .45 |
| Cohort | .004 | |||
| United States | 546 (93) | 538 (90) | 505 (87) | |
| Finland | 41 (7) | 60 (10) | 74 (13) | |
Percentages may not equal 100, because of rounding.
a Threshold cycle tertiles for RSV genomic loads were defined as follows: low, ≥24.3; intermediate, 20.8–24.2; and high, <20.8.
b By the χ2 test.
c Spearman correlation was also performed (P < .001).
d Defined by respiratory, cardiac, neurologic, gastrointestinal, and immunologic diseases.