Asthma is associated with reduced lung function growth between 10 and 18 years while smoking is associated with decline in lung function between 18 and 26 years.
This is important as this suboptimal lung function increase the likelihood that an individual will develop chronic obstructive pulmonary disease.
Association of asthma and smoking with lung function impairment in adolescence and early adulthood: the Isle of Wight Birth Cohort Study
The impact of asthma and smoking on how lung function develops over adolescence and declines over early adulthood was assessed in the 1989 Isle of Wight Birth Cohort. The 1989 Cohort is 1456 individuals who were born in the Isle of Wight in 1989 and 1990. They were assessed at 1, 2, 4, 10, 18 and 26 years of age.
Non-smokers with asthma had lower lung function at age 10, 18 and 26 years compared to individuals without asthma. A blue asthma reliever inhaler reduced this difference. Smokers without asthma had lower lung function from 18 years compared with non-smoking individuals. This did not decrease with a blue asthma reliever inhaler. Smokers with asthma had lower lung function compared to other groups.
Lung function deficits associated with asthma and smoking occur early in life. They are not fully responsive to a blue asthma reliever inhaler. This impairment represents a risk for long-term lung health. It highlights the need to institute preventive measures in adolescence and early adult life before irreversible damage occurs.
Full details can be found in the European Respiratory Journal paper here.