Heterogeneity of reduced FEV₁ in early adulthood: A looking forward, looking backwards analysis

Area of Science:

• Pulmonary Medicine
• Respiratory Health
• Epidemiology

Background:

• Many individuals fail to attain normal peak forced expiratory volume in one second (FEV1) by early adulthood.
• The underlying causes, whether airflow limitation or lung restriction, remain unclear.

Purpose of the Study:

• To investigate the causes of low peak FEV1 in early adulthood.
• To determine if spirometric abnormalities are identifiable in childhood and adolescence.

Main Methods:

• A 5-year prospective follow-up of 19,791 participants (aged 25-35) in the Dutch Lifelines cohort.
• A retrospective analysis of 2,032 participants in the Swedish BAMSE birth cohort with spirometry data from childhood (8-16 years) to young adulthood (24 years).

Main Results:

• In the Lifelines cohort, 8.5% had reduced FEV1, primarily due to Preserved Ratio Impaired Spirometry (PRISm; 68%) or airflow limitation (32%).
• PRISm and airflow limitation were associated with higher smoking exposure and asthma diagnoses.
• These spirometric abnormalities were identifiable as early as 8-16 years of age in the BAMSE cohort.
• FEV1 decline differed significantly between PRISm and normal individuals, suggesting distinct clinical trajectories.

Conclusions:

• Low peak FEV1 in early adulthood is frequently caused by PRISm, contributing to a substantial burden of respiratory symptoms.
• While airflow limitation and normal FEV1 with airflow limitation associate with asthma diagnoses, PRISm does not.
• Differentiated clinical management is necessary for individuals with PRISm, as these abnormalities can be detected in childhood.