Pathway: Non-interventional study to investigate factors influencing treatment decisions in patients with pulmonary hypertension in routine clinical practice.

<bold>Background</bold> Pulmonary arterial hypertension (PAH) is a rare, rapidly progressive, chronic disease defined by high blood pressure in the arteries of the lungs. Current guidelines emphasise the importance of combination therapies to achieve treatment goals. However, real world data show that a large proportion of patients are permanently treated with monotherapy and treatment goals are often not achieved. <bold>Objective</bold> The primary objective of this study is to determine factors that influence treatment decisions in PAH patients in Germany under routine conditions. <bold>Method</bold> An investigator questionnaire was filled out during the patient visits to find out the reasons for the choice of therapy regimen. Regression analyses were used to investigate the influence of various factors on physicians' treatment decisions. <bold>Results</bold> 43 PAH German patients were analysed. Risk status, patient age and comorbidities were the most frequently reasons for the choice of treatment regimen at the start of therapy, while risk status, tolerability and practicability of therapy were the most frequently cited factors during follow-up. Patient age, comorbidities and tolerability were significant reasons for choosing monotherapy. <bold>Conclusion</bold> The analysis showed different pattern at the start of treatment and during follow-up: while patient age and comorbidity status were more frequently documented as reasons at the start of therapy, tolerability profile and practicability of the therapy as well as patient preference were more significant during follow-up. The results show that the treatment decisions in PAH are multifactorial and are based not only on clinical parameters.