Some studies found no clear link between HH and mortality, which might indicate that HH does not significantly impact survival outcomes in certain IPF cohorts.41 43 HH is a condition caused by translocation of the stomach above the diaphragm as well as widening of the oesophageal hiatus, which could be partly caused by degeneration over time affecting the compositional elastin and collagen fibres or due to pressure gradient in between intrathoracic and intra-abdominal.44 This evidence concerns the gene ELN and idiopathic pulmonary fibrosis.