Risk Factors for Mortality and Cardiopulmonary Hospitalization in Systemic Sclerosis Patients At Risk for Pulmonary Hypertension, in the PHAROS Registry.

OBJECTIVE: We sought to identify predictors of mortality and cardiopulmonary hospitalizations in patients at risk for pulmonary hypertension (PH) and enrolled in PHAROS, a prospective cohort study to investigate the natural history of PH in systemic sclerosis (SSc). METHODS: The at-risk population for PH was defined by the following entry criteria: echocardiogram systolic pulmonary arterial pressure > 40 mmHg, or DLCO < 55% predicted or ratio of % forced vital capacity/%DLCO > 1.6, measured by pulmonary function testing. Baseline clinical measures were evaluated as predictors of hospitalization and death between 2005 and 2014. Cox proportional hazards models were censored at date of PH onset or latest study visit and adjusted for age, sex, race, and disease duration. RESULTS: Of the 236 at-risk subjects who were followed for a median of 4 years (range 0.4-8.5 yrs), 35 developed PH after entering PHAROS (reclassified as PH group). In the at-risk group, higher mortality was strongly associated with male sex, low %DLCO, exercise oxygen desaturation, anemia, abnormal dyspnea scores, and baseline pericardial effusion. Risks for cardiopulmonary hospitalization were associated with increased dyspnea and pericardial effusions, although PH patients with DLCO < 50% had the highest risk of cardiopulmonary hospitalizations. CONCLUSION: Risk factors for poor outcome in patients with SSc who are at risk for PH were similar to others with SSc-PH and SSc-pulmonary arterial hypertension, including male sex, DLCO < 50%, exercise oxygen desaturation, and pericardial effusions. This group should undergo right heart catheterization and receive appropriate intervention if PH is confirmed.

Development of pulmonary hypertension in a high-risk population with systemic sclerosis in the Pulmonary Hypertension Assessment and Recognition of Outcomes in Scleroderma (PHAROS) cohort study.

OBJECTIVES: PHAROS registry is a prospective longitudinal cohort study to understand the natural history of pulmonary hypertension (PH) in systemic sclerosis (SSc). METHODS: "At-risk" pulmonary arterial hypertension (PAH) is defined by these entry criteria: echocardiogram (echo) systolic pulmonary arterial pressure (sPAP) >40 mmHg, diffusion lung capacity of carbon monoxide (DLco) <55% predicted, or ratio of percentage forced vital capacity (FVC)/percentage DLco >1.6, as measured by pulmonary function testing (PFT). Patients were followed up annually and right heart catheterization (RHC) performed if PH was suspected. We used descriptive statistics and Kaplan-Meier estimate of time to PH diagnosis. RESULTS: A total of 251 "at-risk" subjects were enrolled between 2005 and 2012 and followed up for mean of 2.5 ± 1.2 years. The mean age at entry was 56.7 ± 11.0 and disease duration was 9.9 ± 8.7 years. Overall, 82 patients had RHC, and 35 were confirmed to have new PH. There were no differences in age, gender, SSc subtypes, antibodies, and disease duration between the "at-risk" and new PH groups. Using Kaplan-Meier survival, the time to PH was 10% at 2 years, 13% at 3 years, and 25% at 5 years. Most new PH patients at entry met the PFT criteria (76%), had significantly higher sPAP (p = 0.013), had shorter 6-min walk distance, and had exercise-induced hypoxia (p = 0.003) than "at-risk" PAH group. CONCLUSIONS: A low DLco, high FVC/DLco, exercise-induced hypoxia and entry echo sPAP > 40 were strongly associated with future PH, though RHC was necessary to confirm PH. This ongoing prospective study confirms that these high-risk factors do predict future PH.