Survival rates in older (>65 years) compared with younger (18–65 years) patients with idiopathic pulmonary arterial hypertension. a) Expected (- - - -) and observed (––––) survival rates and b) age-/sex-matched survival rates. Survival rates in older (>65 years) compared with younger (18–65 years) patients with idiopathic pulmonary arterial hypertension. a) Expected (- - - -) and observed (––––) survival rates and b) age-/sex-matched survival rates. Reproduced from [13] with permission from the publisher. Marius M. Hoeper, and J. Simon R. Gibbs Eur Respir Rev 2014;23:450-457 ©2014 by European Respiratory Society