C-reactive protein and NT-proBNP as surrogate markers for pulmonary hypertension in Gaucher disease.

BACKGROUND

N-terminal pro-Brain Natriuretic Peptide (NT-proBNP) values correlate with mild-moderate pulmonary hypertension assessed by tricuspid insufficiency (TI) gradient>or=30 mm Hg in Gaucher disease. The purpose of this study is to ascertain improved risk stratification based on correlation with NT-proBNP and C-reactive protein (CRP), a standard marker of inflammation.

METHODS

Patients with type I Gaucher disease were selected to reflect differing degrees of echocardiographically determined TI gradient values. NT-proBNP was performed by immunoassay and CRP by standard methods.

FINDINGS: There were 45 patients (18 males; 40%); mean age=42.5 (range: 4-80) years. Median NT-proBNP value=153 (range: 46-6703) pg/ml; median CRP value=0.145 (range: 0.02-2.69) mg/dl. There was a statistically significant correlation between these values (r=0.445, P<0.01). Elevations of CRP and NT-proBNP were risk factors for pulmonary hypertension with odds ratios of 8.47 and 4.9, respectively. The area under the Receiving Operator Characteristic (ROC) curve for diagnosis of pulmonary hypertension was 0.93+/-0.04 for CRP, and 0.7+/-0.1 for NT-proBNP. All patients with pulmonary hypertension had elevation of either CRP or NT-proBNP (100% sensitivity).

CONCLUSIONS

Elevated CRP was a better predictor of pulmonary hypertension in Gaucher disease than elevated NT-proBNP values. Elevated CRP (>0.5 mg/dl) or elevated NT-proBNP (>150 pg/ml) reduces the need to perform echocardiography by more than half, even in this group with over-representation of pulmonary hypertension. The role of inflammatory features in pulmonary hypertension in Gaucher disease is discussed. Further studies are required to ascertain if this approach is useful for prognosis of pulmonary hypertension.