Table 1.
Demographic and Baseline Characteristicsa of Reenrolled Study Participants
| Characteristic | Vaccination Patternb |
||||
|---|---|---|---|---|---|
| Y1 IIV-HD, Y2 IIV-HD (n = 1943) | Y1 IIV-SD, Y2 IIV-HD (n = 1880) | Y1 IIV-HD or -SD, Y2 IIV-HD (n = 3823) | Y1 IIV-HD, Y2 IIV-SD (n = 1890) | Y1 IIV-SD, Y2 IIV-SD (n = 1930) | |
| Female sex | 1125 (57.9) | 1086 (57.8) | 2211 (57.8) | 1070 (56.6) | 1119 (58.0) |
| Age, y, mean (SD) | 74.3 (5.6) | 74.1 (5.5) | 74.2 (5.6) | 74.2 (5.7) | 74.3 (5.7) |
| Race | |||||
| White | 1855 (95.5) | 1789 (95.2) | 3644 (95.3) | 1814 (96.0) | 1856 (96.2) |
| Asian | 10 (0.5) | 11 (0.6) | 21 (0.5) | 9 (0.5) | 10 (0.5) |
| Black/African American | 71 (3.7) | 73 (3.9) | 144 (3.8) | 59 (3.1) | 50 (2.6) |
| Other | 7 (0.4) | 7 (0.4) | 14 (0.4) | 8 (0.4) | 14 (0.7) |
| Hispanic/Latino ethnicity | 79 (4.1) | 75 (4.0) | 154 (4.0) | 77 (4.1) | 90 (4.7) |
| At least 1 prespecified chronic comorbidity | 1321 (68.0) | 1246 (66.3) | 2567 (67.1) | 1281 (67.8) | 1287 (66.7) |
| At least 2 prespecified chronic comorbidities | 654 (33.7) | 631 (33.6) | 1285 (33.6) | 652 (34.5) | 631 (32.7) |
| Cardiac and respiratory disorders | |||||
| Coronary artery disease | 327 (16.8) | 308 (16.4) | 635 (16.6) | 354 (18.7) | 329 (17.0) |
| Atrial fibrillation | 145 (7.5) | 132 (7.0) | 277 (7.2) | 137 (7.2) | 138 (7.2) |
| Valvular heart disease | 82 (4.2) | 82 (4.4) | 164 (4.3) | 93 (4.9) | 92 (4.8) |
| Congestive heart failure | 52 (2.7) | 42 (2.2) | 94 (2.5) | 51 (2.7) | 64 (3.3) |
| COPD | 195 (10.0) | 156 (8.3) | 351 (9.2) | 174 (9.2) | 180 (9.3) |
| Asthma | 185 (9.5) | 152 (8.1) | 337 (8.8) | 163 (8.6) | 176 (9.1) |
Data are presented as No. (%) unless otherwise specified.
Abbreviations: COPD, chronic obstructive pulmonary disease; IIV-HD, high-dose inactivated influenza vaccine; IIV-SD, standard-dose inactivated influenza vaccine; SD, standard deviation; Y1, year 1; Y2, year 2.
a As reported at Y2 enrollment.
b Based on vaccine assigned on randomization in Y2, and vaccine actually received in Y1.