The impact of delayed treatment on 6-minute walk distance test in patients with pulmonary arterial hypertension. a meta-analysis

Background The impact of treatment delay in stable patients with pulmonary arterial hypertension (PAH) remains unaddressed. Methods This meta-analysis included six datasets of PAH therapies with randomized-controlled trials (RCT) and corresponding open-label extension (OLE) studies. We evaluated the change in 6MWD at 1 year in the OLE studies by active treatment versus ex-placebo group. The ex-placebo group (i.e., the patients randomized to placebo in the RCT and ultimately treated with active therapy in the OLE) represented the “delay-in-treatment” population. Results Patients with a treatment delay of 12–16 weeks in PAH targeted therapy had an improvement in 6-minute walk distance (6MWD) test at 1 year, but this improvement did not amount to the same degree of improvement as their initially treated counterparts. The difference in 6MWD was 15 m to 20 m at 1 year. Conclusion A short-term delay in PAH targeted therapy may adversely affect functional capacity in patients with PAH. This meta-analysis provides some insight as to whether earlier treatment would benefit stable patients with PAH.