Risk factors associated with pulmonary arterial hypertension in patients with systemic sclerosis and implications for screening

Pulmonary arterial hypertension (PAH) is a relatively common complication of systemic sclerosis (SSc) affecting 5-12% of patients, and its development is associated with significant morbidity and a particularly poor prognosis. Deaths associated with other complications of SSc, such as renal crisis, have fallen significantly in recent years in line with improvements in their treatment and management. However, mortality due to PAH in this population, although improved, has shown a less dramatic decline. The early diagnosis of PAH in SSc would allow for earlier treatment, before functional and haemodynamic impairment becomes severe; this may further improve outcome, and evidence suggests that screening of SSc patients for PAH is associated with improved survival. In addition, patients with PAH associated with SSc are not a homogeneous population and they differ in terms of disease haemodynamic severity, functional capacity and rate of disease progression. Likewise, management strategies may differ, and the ability to stratify patients may help optimise screening and treatment. A number of patient-, clinical- and disease-specific risk factors associated with the development and prognosis of PAH in SSc have been identified, but their optimal use, alone or in combination, in screening and stratification of patients remains to be established.