During the first TRIBAL scientific reporting period, we have as planned, had a major focus on data collection. TRIBAL is based on the BAMSE birth cohort study established in 1994 and by June 2019, we had completed the 24-year study follow-up. Out of 4,089 original study participants more than 3,000 (75%) answered an extensive electronic questionnaire focusing on chronic respiratory disease symptoms, non-communicable diseases, life-style factors and environmental exposures. In addition, participants have completed the clinical follow-up including advanced lung function measurements, blood sampling and nasal epithelial cell brushing as outlined for the TRIBAL project. In parallel with TRIBAL data collection, data cleaning, database management and quality control activities have been undertaken.
Clinical evaluation of asthma subjects has been performed with longitudinal approaches to evaluate asthma from birth to adulthood to identify those with a persistent asthma phenotype. Importantly, the persistent asthma trajectory group showed more signs of type 2 inflammation than the adolescent-onset trajectory group, and our results highlight the need of identifying patients with adolescent asthma to optimize care, because they suffer the same lack of asthma control as those with persistent asthma. Our immune profiling of asthma subjects revealed distinct cellular phenotypes in overweight/obese individuals with asthma, and targeted proteomics analyses revealed strong associations with biomarkers such as CC16 and CK with persistent asthma.
Identification of subjects with pre-stage COPD and chronic airway disease have resulted in several important findings: Chronic bronchitis is rather common at this young age (5.5%), with active smoking, air pollution exposure and a short period of breastfeeding as significant risk factors. The prevalence of airflow limitation is also rather common (7.2%), whereas lung function impairment corresponding to a COPD diagnosis (i.e. chronic airflow limitation) was, as expected, less common (2%). Several indicators of early life airway infections and respiratory disease as well as environmental exposures (air pollutants in particular) were risk factors associated with COPD according to lung function at this young age. Lung function trajectories from childhood to adulthood have been particularly evaluated with novel findings in relation to lung function catch-up and growth failure. Protein biomarkers linked to impaired lung function have also been identified. Very importantly, improved air quality leads to better lung function growth, which sends a very important message to policy makers.
