Table 1.

Characteristics of patients and controls

	Patients N = 194	Controls N = 273	P‐value
Age (y; median, range)	56 (21‐72)	25 (18‐86)	<.001
Male (n, %)	115 (59%)	137 (50%)	.05
Smoker (n,%)	26 (13%)	37 (14%)	n.s.
Lives alone	26 (13%)	51 (19%)	n.s.
Children in household	50 (26%)	26 (10%)	<.001
Vaccinated against influenza	47 (24%)	68 (25%)	n.s.
Duration since SCT (d; median, range)	679 (23‐9936)
GvHD at time of sampling (n, %)	72 (37%)
Immunosuppression at time of sampling (n, %)	119 (61%)

Abbreviations: GvHD, graft‐vs‐host disease; SCT, allogeneic stem‐cell transplantation.