Based on data from the French Pulmonary Hypertension Registry, anticoagulant use for patients with pulmonary arterial hypertension (PAH) was not associated with improved overall survival, according to a study published Sept. 22 in JACC. Study results were supported by an updated meta-analysis.

A total of 1,597 patients with PAH registered between 2009 and 2020 in the Registry were included in the study. Of them, 380 received anticoagulants at PAH diagnosis. Researchers conducted a propensity score-based analysis, and findings were then incorporated into an updated meta-analysis of nationwide data sets. The primary endpoint was overall survival.

During long-term follow-up, results were similar in patients who did and did not receive anticoagulation therapy at PAH diagnosis, with a median survival was 5.62 years vs. 5.37 years, respectively.

Moreover, findings were consistent across all PAH subgroups. Of note, the updated meta-analysis yielded similar results, with no statistically significant association between survival in PAH and anticoagulant use. Additionally, no significant association was found in two predefined subgroups: idiopathic/heritable PAH or PAH associated with anorexigens, and PAH associated with connective tissue disease.

Laurent Bertoletti, MD, et al., note several limitations of this registry study, including no exclusion in changes of treatment, no accounting for the type of anticoagulant used and the potential of selection bias. "These findings underscore the limitations of observational data in addressing this complex clinical question," they write. "[A randomized controlled trial] remains essential to definitively determine the therapeutic role of anticoagulation in the management of PAH."

In an accompanying editorial comment, Katarina Zeder, MD, and Bradley A. Maron, MD, refer to the study from Bertoletti, et al., as "the most rigorous analysis to date." They write: "These data are compelling and should be considered readily by the practicing community." They continue that future work to resolve this debate definitively may require novel prospective clinical trial designs including pragmatic studies as well as other reports that detail potential outcome differences by anticoagulation status in patients at elevated risk for pulmonary thromboembolic events.