Asthma control and decline in FEV1/FVC ratio over 10 years in adults

Persistent symptoms may predict greater lung function decline in patients with asthma. As part of the ALEC study (EU Horizon 2020 grant #633212), we evaluated FEV1/FVC decline over 10 years in adult asthmatics by disease control and daily ICS use. In the ECRHS II study (1999-2002, baseline), 440 subjects (aged 29-55) with a physician-diagnosed current asthma were classified as well-controlled (non-daily ICS use, n=126; daily ICS use, n=19), partially controlled (145; 33) or uncontrolled (72; 45) patients (GINA 2006). The annual change in pre-bronchodilator FEV1/FVC ratio (%/year) between the ECRHS II and ECRHS III (2010-2013) was computed adjusting for gender, age, smoking habits, BMI and total IgE (>100 kU/L) by a 2-level random-intercept linear model (centre: level 2 unit). On average, patients had a lower FEV1/FVC ratio at baseline according to decreased levels of asthma control (from 79.4 to 73.2%; p<0.001). Compared to well-controlled patients with non-daily ICS use, uncontrolled asthmatics taking daily ICS had 0.14 (95%CI: -0.03, 0.30) %/year additional decline in FEV1/FVC ratio. If history of hospitalizations/ED visits for breathing problems [during the years between the ECRHS I (1991-1993) and ECRHS II] was used as a marker of poor control, uncontrolled asthmatics using daily ICS had 0.42 (95%CI: 0.19, 0.65) %/year additional decline in FEV1/FVC ratio, compared to well-controlled patients who reported non-daily ICS use and no past hospital contacts (p-value for interaction: 0.034). Adults with uncontrolled asthma have greater decline in FEV1/FVC ratio compared to well-controlled subjects even if they report daily ICS use. Those in contact with the hospital seem to be at particular risk of greater decline.