Table 1.

Characteristics of the cases and controls the year before A/H1N1 2009 pandemic influenza

	Cases (n = 44)	Controls (n = 371)	p
Male sex, n (%)	26 (59)	186 (50)	0.26
Age, years, mean (SD)	14.9 (11.0)	20.1 (13.2)	0.01
Mutation CFTR ∆F508/∆F508, n (%)	19 (43)	150 (40)	0.41
Bronchopulmonary bacterial colonization, n (%)
S. aureus	34 (77)	234 (63)	0.063
P. aeruginosa	15 (34)	195 (53)	0.021
FEV1, %, mean (SD)	79 (28)	65 (25)	0.005
FVC, %, mean (SD)	87 (23)	79 (21)	0.073
Cystic fibrosis-specific FEV1, percentiles, mean (SD)	52 (32)	51 (30)	0.78
Antibiotics, number of treatments, mean (SD)
Oral	2.2 (1.9)	2.5 (1.9)	0.17
Intravenous	0.8 (1.5)	1.1 (1.7)	0.20
Oxygen therapy, n (%)	2 (5)	3(4)	0.86
Noninvasive ventilation, n (%)	1 (2)	1(1)	0.69

Both are compared to reference data and expressed as percent predicted values, based on age, gender, and height

FEV1 forced expiratory volume in one second, FVC forced vital capacity, SD standard deviation