Project Details
Projekt
Molecular adaptation to reduced oxygen levels during a long-haul flight simulation in patients with pulmonary hypertension (ICAROS-PH)
Subject Area
Pneumology, Thoracic Surgery
Cardiology, Angiology
Cardiology, Angiology
Term
since 2026
Project identifier
Deutsche Forschungsgemeinschaft (DFG) - Project number 574813881
Acute normobaric (NH) and hypobaric hypoxia (HH) lead to haemodynamic and cardiac changes that are usually well tolerated in healthy individuals, but pose significant risks for patients with pulmonary hypertension (PH). PH affects about 1% of adults and is categorised into different groups according to the Nice classification, including pulmonary arterial hypertension (PAH), left heart disease, chronic lung disease and chronic thromboembolic PH. This disease significantly reduces life expectancy, with 3-year survival rates of 31-54.9 %, depending on the underlying disease. When travelling by air, the reduced air pressure and hypoxic conditions (corresponding to an oxygen level of approximately 15%) can exacerbate PH by increasing pulmonary pressure, exacerbating hypoxia and triggering right heart decompensation. Studies show symptoms such as a drop in oxygen saturation below 85%, dyspnoea and chest pain in up to 38% of patients, but standardised conditions and mechanistic studies are lacking. Particularly little is known about the differences between pre- and post-capillary PH or about molecular effects such as changes in gene expression during air travel. Chronic hypoxia activates hypoxia-inducible factors (HIF), which are transcription factors that control adaptation mechanisms such as haematocrit increase and NO-mediated vasodilation. HIF also influences the inflammatory response by regulating pro- and anti-inflammatory cytokines (e.g. IL-6, VEGF). PH patients exposed to chronic hypoxia show sustained HIF stimulation, which contributes to vascular remodelling and disease progression. Studies suggest that HIF alone does not fully explain the persistent PH phenotype, and further research on metabolic and genetic factors is needed. While the mechanisms of chronic PH are well studied, there is a lack of knowledge on acute molecular changes in PH patients during HH, such as on long-haul flights. Future studies could be crucial to develop safe travelling conditions and therapeutic strategies for PH patients.
DFG Programme
Research Grants
