Pulmonary Hypertension Risk in Patients with Hemoglobin H Disease: Low Incidence and Absence of Correlation with Splenectomy

Pulmonary hypertension (PHT) is a common complication for patients with β thalassemia intermediate (TI), especially splenectomized patients. However, the frequency and risk factors of PHT in patients with hemoglobin H (HbH) disease is unknown. The purpose of this study was to identify the prevalence of PHT risk manifested as tricuspid regurgitant jet velocity (TRV) ≥2.5 m/s in patients with HbH disease and its correlation with splenectomy. One hundred and ninety-eight patients with HbH disease who visited the 303rd Hospital of the People's Liberation Army (Nanning, China) were investigated. Thirteen subjects (6.5%) were diagnosed as having a risk of PHT. Regression analyses showed that the prevalence of PHT risk was correlated only with age (r = 0.195, p = 0.006) and not with splenectomy. The risk of PHT in patients older than 35 years was 5.7 times (range 1.8-18.6) greater than that for patients younger than 35 years. For splenectomized patients compared to those with HbH disease, patients with TI had a higher frequency of PHT risk, higher nucleated red blood cell counts (46.03 ± 41.11 × 10(9)/l vs. 0.18 ± 1.19 × 10(9)/l, p < 0.001) and a higher platelet counts (837.6 ± 178.9 × 10(9)/l vs. 506.7 ± 146.2 × 10(9)/l, p < 0.001). PHT risk is low in patients with HbH disease and does not correlate with splenectomy. Patients older than 35 years should be monitored regularly.