Racial differences in patients referred for right heart catheterization and risk of pulmonary hypertension.

African Americans (AA) have a higher incidence of pulmonary hypertension (PH) risk factors. Few studies have examined the racial differences in the prevalence and etiology of PH and direct comparison of invasive hemodynamics between AAs and Caucasians has rarely been reported. In this study, we examined whether racial differences exist in patients referred for right heart catheterization (RHC) and hypothesized that AA race is an independent risk factor for PH and is associated with increased adjusted mortality. We extracted data for AA and Caucasian patients who underwent RHC at Vanderbilt between 1998 and 2014. Clinical information was obtained from Vanderbilt's Synthetic Derivative, a de-identified mirror of our Electronic Medical Record. A total of 4576 patients were analyzed, including 586 (13%) AAs and 3990 (87%) Caucasians. AAs were younger than Caucasians by an average of eight years, but had more prevalent heart failure, features of metabolic syndrome, and higher creatinine. AAs also had higher mean pulmonary artery pressure and pulmonary vascular resistance. After adjusting for relevant co-morbidities, the AA race is associated with 41% increased risk of PH (odds ratio [OR] = 1.41, 95% confidence interval [CI] = 1.12-1.79). Among patients with PH, AA race is associated with 24% increased adjusted mortality (hazard ratio [HR] = 1.24, 95% CI = 1.09-1.45). AAs were younger but had more prevalent cardiometabolic and renal disease and worse pulmonary hemodynamics. The AA race is an independent risk factor for PH. Among patients with PH, the AA race is associated with increased adjusted mortality. Future studies should focus on delineating whether genetic or environmental factors contribute to PH risk in AAs.