Complications of β-Thalassemia Intermedia in Iran During 1996–2010 (Single-Center Study)

Abstract

Patients with thalassemia intermedia (TI) experience many complications, of which the incidence varies greatly among cases. Considering the high prevalence of thalassemia in Iran, the study was carried out to determine the frequency of TI complications in Iranian patients and to find possible risk factors for each of them. Using the sampling method of "census," the authors included 153 patients who were seen in their tertiary hematology clinic with the diagnosis of TI during 1996-2010; an analytical cross-sectional study was performed and the data was analyzed by SPSS software using univariate and regression analyses. Mean age of the patients at the time of the study was 17.4 years and 36.5% were receiving transfusions (regularly or occasionally). Mean hemoglobin was 9.2 g/dL and mean serum ferritin was 858 ng/mL. Splenectomy was performed in 46.9% and it was correlated with age and the age at diagnosis in regression analysis. Cholelithiasis was found in 25.5% and was correlated with age and history of splenectomy. Pulmonary hypertension, detected in 23.5%, was correlated with thrombocytosis and mitral valve regurgitation in univariate analysis. Endocrine disease (hypogonadism, hypothyroidism, and adrenal insufficiency) was detected in 8% of the patients. In univariate analysis, endocrine disease was correlated with age of the patients. Regarding bone density of the spine, 53% of cases had osteoporosis. Thrombocytosis was present in 42% of patients and was correlated with their age. Since the severity of thalassemia intermedia vary greatly among patients, a careful evaluation of clinical, laboratory, and genetic aspects is necessary to differentiate TI in a patient at presentation. Moreover, TI patients should be carefully followed up for early detection and management of newly developed complications. The authors also suggest confirmatory controlled studies with larger sample sizes to assist in developing guidelines for surveillance and treatment of TI.

Prevalence and Risk Factors for Pulmonary Arterial Hypertension in a Large Group of β-Thalassemia Patients Using Right Heart Catheterization

“…Nonetheless, and similar to patients with Class 4 pulmonary hypertension attributed to chronic thromboembolic disease, hypercoagulability can play a major role in the cause of PAH, where thrombi may be present in both the small distal pulmonary arteries and the proximal elastic pulmonary arteries. 7 The association of splenectomy and older age with increased PAH risk in our study echoes previous reports 18,19,22,24,25,33,35,[39][40][41] and further supports the latter hypothesis. Abnormalities of platelets and hemolyzed red blood cells are believed to be the key factors causing hypercoagulability and subsequent thrombotic events in β-thalassemia; especially older, splenectomized, β-thalassemia intermedia patients.…”

“…Owing to the systematic approach undertaken in our study, we believe that estimates presented in this report are more likely representative of the true PAH prevalence in patients with β-thalassemia. Our study echoed previous reports demonstrating that the prevalence of PAH is higher in β-thalassemia intermedia than β-thalassemia major [16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33] but did not observe the previously reported female predominance. 34,35 The correlation between sPAP as estimated on echocardiography and as measured on right heart catheterization was only moderately good in our study.…”

“…42 The association of thrombocytosis, increased platelet activation, increased levels of nucleated red blood cells, and other markers of hypercoagulability with PAH in patients with β-thalassemia (mostly intermedia) have been reported, even in patients with no evidence or history of pulmonary embolic disease. 19,24,25,34,39,43 Other factors are also suggested to cause PAH in β-thalassemia. Associations between lower hemoglobin levels and increased markers of hemolysis with this morbidity have been reported.…”

“…Previous studies relying solely on echocardiographic parameters reported prevalence rates ranging between 10% and 78.8% (averaging ≈30%). [16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31][32][33] The diagnosis was usually established based on a TRV exceeding 2.5-2. study, the prevalence of PAH was considerably lower when more strict echocardiographic criteria and confirmatory right heart catheterization were used. Owing to the systematic approach undertaken in our study, we believe that estimates presented in this report are more likely representative of the true PAH prevalence in patients with β-thalassemia.…”

A prospective analysis for prevalence of complications in Thai nontransfusion‐dependent Hb E/β‐thalassemia and α‐thalassemia (Hb H disease)

“…In contrary, a cohort study of TI patients has shown terrifying evidence that β‐TI patients representing NTDT had a much higher incidence of several thalassemia related complications compared to β‐TM who were well‐treated . This finding was consistent with several studies from Mediterranean countries, the Middle East, and Indian subcontinents . However, there were limited data of the prevalence of thalassemia related complications in NTDT from Southeast Asian populations and none was a prospective study.…”