Table 2.
Characteristics of Acute Respiratory Illness–Associated Hospitalizations by Influenza Vaccination and Test Status, VISION Network
| Characteristic | Total, No. (Column %) | Influenza Vaccination Status | Influenza Test Result | ||||
|---|---|---|---|---|---|---|---|
| Unvaccinated, No. (Row %) |
Vaccinated, No. (Row %) |
SMDa | Negative, No. (Row %) |
Positive, No. (Row %) |
SMDa | ||
| All hospitalizations | 19 751 (100.0) | 9318 (47.2) | 10 433 (52.8) | … | 17 877 (90.5) | 1874 (9.5) | … |
| Influenza vaccination status | |||||||
| Unvaccinated | 9318 (47.2) | 9318 (100.0) | 0 (0.0) | … | 8177 (87.8) | 1141 (12.2) | 0.307 |
| Vaccinated | 10 433 (52.8) | 0 (0.0) | 10 433 (100.0) | … | 9700 (93.0) | 733 (7.0) | … |
| Month of encounter | |||||||
| October 2022 | 1165 (5.9) | 818 (70.2) | 347 (29.8) | 0.352 | 1131 (97.1) | 34 (2.9) | 1.168 |
| November 2022 | 3791 (19.2) | 2169 (57.2) | 1622 (42.8) | … | 3203 (84.5) | 588 (15.5) | … |
| December 2022 | 4654 (23.6) | 2215 (47.6) | 2439 (52.4) | … | 3667 (78.8) | 987 (21.2) | … |
| January 2023 | 3896 (19.7) | 1672 (42.9) | 2224 (57.1) | … | 3677 (94.4) | 219 (5.6) | … |
| February 2023 | 3169 (16.0) | 1283 (40.5) | 1886 (59.5) | … | 3135 (98.9) | 34 (1.1) | … |
| March 2023 | 3076 (15.6) | 1161 (37.7) | 1915 (62.3) | … | 3064 (99.6) | 12 (0.4) | … |
| Site | |||||||
| Site A | 2238 (11.3) | 1140 (50.9) | 1098 (49.1) | 0.318 | 1936 (86.5) | 302 (13.5) | 0.170 |
| Site B | 5098 (25.8) | 3034 (59.5) | 2064 (40.5) | … | 4592 (90.1) | 506 (9.9) | … |
| Site C | 12 415 (62.9) | 5144 (41.4) | 7271 (58.6) | … | 11 349 (91.4) | 1066 (8.6) | … |
| Age, y, median (IQR) | 74 (62–83) | 68 (55–79) | 77 (68–84) | … | 74 (62–83) | 72 (59–81) | … |
| Age group, y | |||||||
| 18–64 | 5794 (29.3) | 3877 (66.9) | 1917 (33.1) | 0.524 | 5133 (88.6) | 661 (11.4) | 0.141 |
| ≥65 | 13 957 (70.7) | 5441 (39.0) | 8516 (61.0) | … | 12 744 (91.3) | 1213 (8.7) | … |
| Sex | |||||||
| Female | 10 479 (53.1) | 4908 (46.8) | 5571 (53.2) | 0.015 | 9427 (90.0) | 1052 (10.0) | 0.068 |
| Male | 9272 (46.9) | 4410 (47.6) | 4862 (52.4) | … | 8450 (91.1) | 822 (8.9) | … |
| Race | |||||||
| White | 13 614 (68.9) | 6258 (46.0) | 7356 (54.0) | 0.190 | 12 344 (90.7) | 1270 (9.3) | 0.099 |
| Black | 1606 (8.1) | 976 (60.8) | 630 (39.2) | … | 1421 (88.5) | 185 (11.5) | … |
| Otherb | 2712 (13.7) | 1132 (41.7) | 1580 (58.3) | … | 2490 (91.8) | 222 (8.2) | … |
| Unknown | 1819 (9.2) | 952 (52.3) | 867 (47.7) | … | 1622 (89.2) | 197 (10.8) | … |
| Ethnicity | |||||||
| Hispanic | 2617 (13.2) | 1340 (51.2) | 1277 (48.8) | 0.063 | 2333 (89.1) | 284 (10.9) | 0.060 |
| Non-Hispanic | 17 134 (86.8) | 7978 (46.6) | 9156 (53.4) | … | 15 544 (90.7) | 1590 (9.3) | … |
| Any medical condition | |||||||
| Yes | 19 353 (98.0) | 9032 (46.7) | 10 321 (53.3) | 0.140 | 17 545 (90.7) | 1808 (9.3) | 0.103 |
| No | 398 (2.0) | 286 (71.9) | 112 (28.1) | … | 332 (83.4) | 66 (16.6) | … |
| Respiratory condition | … | … | … | … | … | … | … |
| Yes | 15 904 (80.5) | 7324 (46.1) | 8580 (53.9) | 0.092 | 14 566 (91.6) | 1338 (8.4) | 0.239 |
| No | 3847 (19.5) | 1994 (51.8) | 1853 (48.2) | … | 3311 (86.1) | 536 (13.9) | … |
| Nonrespiratory condition | |||||||
| Yes | 18 746 (94.9) | 8613 (45.9) | 10 133 (54.1) | 0.212 | 17 031 (90.9) | 1715 (9.1) | 0.151 |
| No | 1005 (5.1) | 705 (70.1) | 300 (29.9) | … | 846 (84.2) | 159 (15.8) | … |
| Immunosuppressive condition | |||||||
| Yes | 4728 (23.9) | 2025 (42.8) | 2703 (57.2) | 0.098 | 4414 (93.4) | 314 (6.6) | 0.197 |
| No | 15 023 (76.1) | 7293 (48.5) | 7730 (51.5) | … | 13 463 (89.6) | 1560 (10.4) | … |
| IMV | |||||||
| Yes | 1673 (8.5) | 919 (54.9) | 754 (45.1) | 0.094 | 1579 (94.4) | 94 (5.6) | 0.151 |
| No | 18 078 (91.5) | 8399 (46.5) | 9679 (53.5) | … | 16 298 (90.2) | 1780 (9.8) | … |
| ICU admission | |||||||
| Yes | 3504 (17.7) | 1663 (47.5) | 1841 (52.5) | 0.005 | 3276 (93.5) | 228 (6.5) | 0.172 |
| No | 16 247 (82.3) | 7655 (47.1) | 8592 (52.9) | … | 14 601 (89.9) | 1646 (10.1) | … |
| Death | |||||||
| Yes | 1172 (5.9) | 514 (43.9) | 658 (56.1) | 0.034 | 1114 (95.1) | 58 (4.9) | 0.149 |
| No | 18 579 (94.1) | 8804 (47.4) | 9775 (52.6) | … | 16 763 (90.2) | 1816 (9.8) | … |
Abbreviations: ICU, intensive care unit; IMV, invasive mechanical ventilation; IQR, interquartile range; SMD, standardized mean difference.
a
An absolute SMD >0.20 indicates a nonnegligible difference in variable distributions between hospitalizations for vaccinated versus unvaccinated patients or for patients with positive influenza test results versus patients with negative influenza test results.
b
Other race defined as any 1 of the following responses: Asian, Hawaiian or other Pacific Islander, American Indian or Alaska Native, other, multiple races.