Hiller AM, et al. - Given that a variable annual decline in FEV₁ (forced expiratory volume in one second) (∆FEV₁) has been reported in previous studies on lung function in subjects with severe alpha-1 antitrypsin deficiency (AATD), researchers assessed ∆FEV₁ and determined risk factors for ∆FEV₁ in severe AATD cases in this study. They used the Swedish AATD Register and the Swedish National Patient Register to extract data regarding smoking habits, symptoms, outcomes of lung function tests and exacerbations. Participants included 104 (9%) current smokers, 539 (48%) ex-smokers and 489 (43%) never-smokers, observed from 1991 to 2016. The factors that showed relation to an accelerated lung function decline in individuals with severe AATD were active smoking, age, respiratory symptoms at baseline and repeated severe exacerbations of chronic obstructive pulmonary disease.