Dual exposure to smoking and household air pollution is associated with an increased risk of severe asthma in adults in Brazil

Table 4 Spirometric parameters of the individuals with asthma (mild to moderate and severe) studied

Characteristics	Smokers (n = 78)	Household pollution (n = 358)	Double exposure (n = 155)	No exposure (n = 405)	P^§
Pre-BD*
FEV₁	75 ± 18^b.c	70 ± 19^d.e	66 ± 17^f	74 ± 18	< 0.001
FEV₁/FVC ^††	0.73 ± 0.12	0.71 ± 0.13^e	0.71 ± 0.14^f	0.73 ± 0.13	0.073
FEF_25–75 %	64 ± 34^c	57 ± 35^d.e	46 ± 27^f	65 ± 32	< 0.001
Post-BD*
FEV₁	82 ± 17^b.c	76 ± 18^d.e	72 ± 16^f	80 ± 17	< 0.001
FEV₁/FVC^††	0.76 ± 0.12^c	0.74 ± 0.12^e	0.72 ± 0.13^f	0.77 ± 0.13	0.001
FEF_25–75 %	76 ± 36^b.c	66 ± 38^d.e	52 ± 28^f	77 ± 34	< 0.001
FEV₁ post-BD < 80%^†	28 (35.9)^b.c	203 (56.7)^d.e	101 (65.2)^f	180 (44.4)	< 0.001
FEV₁/FVC post-BD < 70%^†;††	25 (32.1)	127 (35.5)^e	60 (38.7)^f	111 (27.4)	0.036
FEF _25–75 % pre-BD < 60%^†	41 (52.6)^c	221 (61.7)^d.e	110 (71.0)^f	191 (47.2)	< 0.001

ISSN: 2045-7022