The RHINE IV study, conducted between 2020 and 2023, represents the third follow-up to the original RHINE study.

In this phase, we are approaching a true adult lifespan cohort, with immense research possibilities for the benefits of public health. The study population will now be 50-75 years old, with a thirty-year follow-up time. This provides the perfect opportunity for measuring lifespan exposures and long-term outcomes, and to thoroughly map changes in exposures over time.

Overall aims of RHINE IV:
1. To examine what happens to lung health as persons grow older, and to investigate the role of both harmful and beneficial factors for ageing lung health.

2. To examine how respiratory diseases and comorbidities such as sleep disorders, cardiovascular diseases and diabetes interact with each other with increasing age.

Within these overall aims, the aims from the previous RHINE stages are kept, but with a focus on ageing populations. With harmful and beneficial factors, we refer to exposures of both short and long durations (0-30 years exposure periods) such as smoking habits, comorbidities, occupational exposures, early life exposures, family history of diseases, physical activity, metabolic status, dental health, health-related quality of life, sleep, indoor and outdoor environment.

With lung health we refer to respiratory diseases such as asthma, allergic rhinitis and COPD, but also to respiratory symptoms such as cough and wheeze, and in recent times also COVID-19 infection. The outcomes will be based on questionnaires, but also revolve around data from national registries (cause of death registry, hospital registry, and prescription registry).
A particular focus for this third follow-up of the RHINE study will be on health effects of long-term air pollution and greenness exposures.