Characteristics | Unvaccinated before entry | Vaccinated before entry | p-value# |
Subjects n | 6255 | 4986 | |
Age group yr¶ | |||
65–74 | 3903 (62.4) | 2302 (46.2) | <0.0001 |
75–84 | 1780 (28.5) | 2080 (41.7) | |
≥85 | 572 (9.1) | 604 (12.1) | |
Sex | |||
Male | 2716 (43.4) | 2176 (43.6) | 0.814 |
Female | 3539 (56.6) | 2810 (56.4) | |
Influenza vaccination previous yr | 1917 (30.6) | 4115 (82.5) | <0.001 |
High blood pressure | 2988 (47.8) | 3002 (60.2) | <0.0001 |
Obesity | 937 (15.0) | 1038 (20.8) | <0.0001 |
Diabetes mellitus | 1294 (20.7) | 1356 (27.2) | <0.0001 |
Chronic heart disease | 623 (10.0) | 717 (14.4) | <0.0001 |
Chronic lung disease | 598 (9.6) | 701 (14.1) | <0.0001 |
Smokers | 569 (9.1) | 361 (7.2) | <0.0001 |
Immunocompromised status | 652 (10.4) | 794 (15.9) | <0.0001 |
Data are presented as n (%), unless otherwise stated. #: p-values were calculated with the Chi-squared test; ¶: the median ages of the unvaccinated and vaccinated subjects were 73.4 and 75.9, respectively.