Joint trajectories of wheezing, asthma, and rhinitis in birth and adult cohorts

Background: Despite their clinical overlap, wheezing, asthma, and rhinitis are often managed in isolation. Aim: to identify and characterise joint trajectories of these conditions using a unified analytical framework in childhood and adulthood. Methods: We used data from the population-based INfancia y Medio Ambient (INMA) birth cohort (Spain, ages 6–18 years), and the European Community Respiratory Health Survey (ECRHS) adult cohort (11 European countries and Australia, ages 19–67-years). Wheezing, asthma, and rhinitis symptoms, and a wide range of clinical and risk factors, were assessed using harmonised questionnaires and standardised tests. We identified trajectories separately for each cohort using longitudinal k-means clustering. Results: Five joint trajectories were identified in children (INMA, n=959) and seven in adults (ECRHS, n=9275). An asymptomatic trajectory was most prevalent in both cohorts (58% and 48%, respectively). Rhinitis-only trajectories appeared as persistent (17% children, 11% adults) or with onset at various life stages (adolescence to late-adulthood). A persistent multimorbidity trajectory was identified in both groups (6–7%), characterised by high maternal asthma, frequent respiratory symptoms, and low lung function. Age-specific trajectories included resolving wheezing/asthma in children (7%, linked to frequent respiratory infections) and, in adults, resolving mid-adulthood rhinitis (7%, with high maternal eczema/allergy), and wheezing with rhinitis (10%, uniquely associated to high smoking, low education, manual occupations, and impaired lung function). Conclusion: We identified both shared and age-specific trajectories of wheezing, asthma, and rhinitis across the lifespan. These distinct trajectories, ranging from isolated rhinitis to environment-driven multimorbidity, demand age-tailored, integrated clinical management, and investigation into underlying biological mechanisms.