Factors Associated with Referral to Expert Providers among Patients with Pulmonary Hypertension.

Rationale: Guidelines recommend early referral to pulmonary hypertension (PH) experts for patients with confirmed or suspected pulmonary arterial hypertension (PAH) or chronic thromboembolic PH (CTEPH), among others. Yet, patients often have advanced disease at the time of referral. The drivers of these referral delays are not well known.

Objectives: Building upon our prior qualitative findings on barriers to timely PH care along the care continuum, we sought to identify patient-level factors associated with referral to PH experts.

Methods: We leveraged the Massachusetts All-Payer Claims Database to identify all patients with incident PH in 2015-2017 using a validated algorithm (sensitivity 28%; specificity 100%) and further identified subgroups with a risk factor for PAH and CTEPH. Our outcome was presence or absence of referral to a PH expert during the study period. Based on our prior qualitative work, our three primary exposures were 1) Medicaid recipient, 2) mental health diagnoses, and 3) distance to the nearest PH center. We conducted separate multivariable logistic regression models to determine the association between each of our primary exposures and outcome, among our entire cohort and those with a risk factor for PAH and CTEPH.

Results: Among our entire cohort (n=12,505), 704 (5.6%) were seen by a PH expert. Among the subset with a risk factor for PAH (n=2,393) and CTEPH (n=3,167), 242 (10.1%) and 185 (5.8%) were seen by a PH expert, respectively. Patients less likely to be referred included Medicaid recipients (adjusted Odds Ratio [aOR] 0.64, 95% Confidence Interval [CI] 0.53-0.77), those with mental health diagnoses (aOR 0.69, 95% CI 0.58-0.83), and those living further from a PH center (aOR 0.78, 95% CI 0.74-0.82 for each 10 miles increase in distance to PH center). Findings were similar among those with a risk factor for PAH and CTEPH.

Conclusions: Few patients with PH are referred to PH experts, including those with a risk factor for PAH and CTEPH. Factors associated with expert referral identified in this study highlight barriers to timely PH care and offer targeted areas of future study to improve the timeliness of PH care.