Significance of serum uric acid in pulmonary hypertension due to systemic sclerosis: a pilot study.

Systemic sclerosis is a connective tissue disease, which may lead to elevated pulmonary arterial pressure due to pulmonary arterial hypertension and/or left ventricular diastolic dysfunction. Uric acid (UA) has been shown to be elevated in patients with pulmonary hypertension (PH) and heart failure. We aimed to investigate the potent relationship between serum UA and pulmonary pressure as well as functional capacity in patients with SSc. We studied 66 patients (mean age 57.7±12.1years, 63 women), presenting with SSc. Systolic pulmonary artery pressure assessed by echocardiography, lung function tests, six-minute walk test (6MWT) and serum UA levels were recorded in all patients. In 24 (36%) patients, the diagnosis of PH was established by echocardiography (systolic pulmonary artery pressure ≥40 mmHg). Patients with PH had higher UA serum levels compared to patients without PH (5.1±2.1 mg/dl vs. 4.2±0.9 mg/dl, p=0.04). Among patients with PH, UA values were inversely correlated with the SMWT distance (r=-0.51, p=0.01). Serum UA values increased in proportion to the functional capacity in PH patients with scleroderma. Further investigations in prospective studies will unfold in detail the pathophysiological significance of UA in SSc patients with PH and determine its role as a prognostic marker in the assessment and monitoring of the disease.