Heterogeneity of reduced <scp>FEV<sub>1</sub></scp> in early adulthood: A looking forward, looking backwards analysis
Núria Olvera, Àlvar Agustí, Judith M. Vonk, Gang Wang, Jenny Hallberg, H. Marike Boezen, Maarten van den Berge, Erik Melén, Rosa Faner
Abstract
Abstract Background Some individuals never achieve normal peak FEV 1 in early adulthood. It is unknown if this is due to airflow limitation and/or lung restriction. Methods To investigate this, we: (1) looked forward in 19,791 participants in the Dutch Lifelines general population cohort aged 25–35 years with 5‐year follow‐up; and (2) looked backwards in 2032 participants in the Swedish BAMSE birth cohort with spirometry at 24 years of age but also at 16 and/or 8 years. Results (1) In Lifelines 8.5% of participants had reduced FEV 1 at 25–35 years, 68% due to Preserved Ratio Impaired Spirometry (‘PRISm’) and 32% to airflow limitation (‘low‐limited’); besides, 3.8% participants with normal FEV 1 showed airflow‐limitation (‘normal‐limited’). Low‐limited and normal‐limited, but not PRISm, reported higher smoking exposures and asthma diagnosis than normal ( p < 0.05). At 5‐year follow‐up, 91.2% of participants remained in the same group, and FEV 1 decline was similar in normal and normal‐limited participants, but statistically smaller ( p < 0.05) in PRISm and low‐limited; (2) these observations were largely reproduced in BAMSE at 24 years of age; and, (3) in BAMSE, low‐limited or PRISm individuals were already identifiable at 8–16 years of age. Conclusion Low peak FEV 1 in early adulthood is most often due to PRISm and results in a significant burden of respiratory symptoms. Only low‐limited and normal‐limited, but not PRISm, associate with a doctor diagnosis of asthma, and FEV 1 decline was statistically different in PRISm indicating a need for differentiated clinical approaches. These spirometric abnormalities can be already identified in childhood and adolescence.