Background: Comorbidities can affect disease progression and/or response to treatment in various conditions. Comorbid conditions are prevalent in patients with pulmonary arterial hypertension (PAH); however, their effect on patient outcomes remains unknown.
Methods: We evaluated the effect on functional class (FC), 6-min walk test distance (6MWD), and survival of the seven most common, comorbid conditions at enrollment in patients with PAH from the Registry to Evaluate Early and Long-term PAH Disease Management (REVEAL Registry): hypertension, clinical depression, type 2 diabetes mellitus (diabetes), obesity, COPD, sleep apnea, and thyroid disease.
Results: Patients with COPD or diabetes had the shortest 6MWD at enrollment (304.5 and 304.6 m, respectively) vs other comorbidities. Adjusted linear regression for 6MWD at enrollment revealed significant reductions among patients who were hypertensive, obese, diabetic, or had COPD (P<.001). A larger proportion of patients who were obese or had COPD were FC III/IV vs FC I/II at enrollment (P<.001). There was a greater risk for death among patients with diabetes (hazard ratio [HR], 1.73; 95% CI, 1.40-2.13; P<.001) or COPD (HR, 1.59; 95% CI, 1.34-1.90; P<.001), but there was a reduced risk for death in patients who were obese (HR, 0.73; 95% CI, 0.61-0.86; P<.001).
Conclusions: Compared with other analyzed comorbidities in patients with PAH, hypertension, obesity, diabetes, and COPD were associated with significantly worse 6MWD; obesity and COPD were associated with worse FC; and diabetes and COPD were associated with increased risk for death. Further investigation of the effects of treating these comorbidities in patients with PAH is warranted.
Trial registry: ClinicalTrials.gov; Identifier: NCT00370214; URL: www.clinicaltrials.gov.