Figure 2From: Fixed airways obstruction among patients with severe asthma: findings from the Singapore General Hospital-Severe Asthma Phenotype Study Pack-year smoking history of subjects according to postbronchodilator FEV 1 % predicted. Patients with postbronchodilator FEV1 % < 70% had a higher pack-year smoking than patients with postbronchodilator FEV1 % ≥ 70% (Mann–Whitney, p = 0.022).Back to article page