Table 1.
Characteristics of the study population at the index datea by vaccination status
| Characteristicb | Unvaccinated (n = 66 492) | Vaccinated (n = 11 864) | Overall (n = 78 356) |
|---|---|---|---|
| Age, median (IQR), y | 59 (53 – 65) | 74 (70 – 80) | 61 (54 – 69) |
| Sex | |||
| Male | 32676 (49.1) | 5351 (45.1) | 38027 (48.5) |
| Female | 33816 (50.9) | 6513 (54.9) | 40329 (51.5) |
| Race | |||
| Asian | 23551 (35.4) | 5550 (46.8) | 29101 (37.1) |
| White | 19846 (29.8) | 3627 (30.6) | 23473 (30.0) |
| More Than One Race | 10586 (15.9) | 1735 (14.6) | 12321 (15.7) |
| Native Hawaiian/Other Pacific Islander | 6122 (9.2) | 575 (4.8) | 6697 (8.5) |
| Black | 641 (1.0) | 54 (0.5) | 695 (0.9) |
| American Indian/Alaska Native | 165 (0.2) | 13 (0.1) | 178 (0.2) |
| Unknownc | 5581 (8.4) | 310 (2.6) | 5891 (7.5) |
| Ethnicity | |||
| Hispanic/Latino | 3060 (4.6) | 351 (3.0) | 3411 (4.4) |
| Not Hispanic/Latino | 59341 (89.2) | 11339 (95.6) | 70680 (90.2) |
| Unknownd | 4091 (6.2) | 174 (1.5) | 4265 (5.4) |
| Inpatient Care (IC) e | |||
| ≥1 Visits | 3979 (6.0) | 1188 (10.0) | 5167 (6.6) |
| No Visits | 62513 (94.0) | 10676 (90.0) | 73189 (93.4) |
| Institutional Stay (IS) e | |||
| ≥1 Visits | 762 (1.1) | 168 (1.4) | 930 (1.2) |
| No Visits | 65730 (98.9) | 11696 (98.6) | 77426 (98.8) |
| Emergency Department Visit (ED) e | |||
| ≥1 Visits | 9977 (15.0) | 2221 (18.7) | 12198 (15.6) |
| No Visits | 56515 (85.0) | 9643 (81.3) | 66158 (84.4) |
| Ambulatory Visit (AV), median (IQR) e | 3 (1 – 7) | 6 (3 – 11) | 4 (1 – 8) |
| Deyo comorbidity index, median (IQR) f | 0 (0 – 1) | 1 (0 – 3) | 0 (0 −1) |
| Prior ZVL vaccination within 1 year of index date | |||
| Yes | 1981 (3.0) | 296 (2.5) | 2277 (2.9) |
| No | 64511 (97.0) | 11568 (97.5) | 76079 (97.1) |
| Follow up time (days), median (IQR) | 730 (430 – 730) | 730 (730 – 730) | 730 (480 – 730) |
IQR = Interquartile range.
a
The index date was defined as the date at which an individual was eligible for study inclusion.
b
Values are reported as No. (%) unless otherwise indicated.
c
The unknown race category includes individuals with either unknown or missing race.
d
The unknown ethnicity category includes individuals with either unknown or missing ethnicity.
e
Healthcare utilization was assessed in the 1 year prior to the index date.
f
Deyo comorbidity index was assessed in the 1 year prior to the index date