Case group

Control group

Male/total

32/36 (88.9%)

Age

76.6 (SDa 8.6)

76.9 (SDa 8.3)

HOT period (year)

1.8 (SDa 2.0)

1.8 (SDa 2.1)

A(H1N1)2009 vaccination

17/36 (47.2%)

23/36 (63.9%)

Seasonal influenza vaccination

5/32 (15.6%)

9/33 (27.3%)

Incidence of influenza

0/32 (0.0%)

0/33 (0.0%)

Diabetes mellitus

2/34 (5.9%)

4/35 (11.4%)

Current smoking

1/34 (2.9%)

1/35 (2.9%)

aStandard deviation
Table 1: Characteristics of the patients.