Economic burden of illness among patients with pulmonary arterial hypertension (PAH) associated with connective tissue disorders (CTD).

Pulmonary arterial hypertension (PAH) is commonly associated with connective tissue disorders (CTDs). This study provides a contemporary assessment of the economic burden of CTD + PAH and PAH in the United States. Eligible adult patients identified from Optum's deidentified Clinformatics® Data Mart Database (10/01/2015-09/30/2021) were classified into mutually exclusive cohorts based on recorded diagnoses: (1) CTD + PAH, (2) PAH, (3) CTD, (4) control without CTD/PAH. The index date was a randomly selected diagnosis date for PAH (CTD + PAH, PAH cohorts) or CTD (CTD cohort), or a random date (control cohort). Entropy balancing was used to balance characteristics across cohorts. Healthcare costs and healthcare resource utilization (HRU) per patient per month (PPPM) were assessed for ≤12 months postindex and compared among balanced cohorts. A total of 552,900 patients were included (CTD + PAH:  = 1876; PAH:  = 8177; CTD:  = 209,156; control:  = 333,691). Average total all-cause costs were higher for CTD + PAH than PAH cohort ($16,854 vs. $15,686 PPPM;  = 0.02); both cohorts incurred higher costs than CTD and control cohorts ($4476 and $2170 PPPM; all  < 0.001). Average HRU PPPM was similar between CTD + PAH and PAH cohorts (inpatient stay: 0.15 vs. 0.15, outpatient visits: 4.23 vs. 4.11; all  > 0.05), while CTD and control cohorts incurred less HRU (inpatient stay: 0.07 and 0.03, outpatient visits: 2.67 and 1.69; all  < 0.001). CTD + PAH and PAH are associated with a substantial economic burden. The incremental burden attributable to PAH versus the general population and patients with CTD without PAH highlights significant unmet needs among PAH patients.