Lipoprotein-associated phospholipase A2 (Lp-PLA2) and tumor necrosis factor-alpha (TNF-α) and their relation to premature atherosclerosis in β-thalassemia children

Abstract

Background/Objectives

Beta (β)-thalassemia adults are prone to premature atherosclerosis but data about this complication among thalassemia children are few. Lipoprotein-associated phospholipase A2 (Lp-PLA2) and tumor necrosis factor-α (TNF-α) are inflammatory markers that could be implicated in atherosclerotic process. We investigated Lp-PLA2 and TNF-α levels in β-thalassemia children and their relation to subclinical atherosclerosis.

Methods

Twenty-two β-thalassemia major (TM), 20 β-thalassemia intermedia children, and 30 age- and sex-matched healthy controls were included. Lipid profile (by colorimetric assay), serum ferritin, TNF-α, and plasma Lp-PLA2 levels (by enzyme-linked immunosorbent assay technique) were estimated. Carotid intima-media thickness (cIMT) was measured by high-resolution ultrasound.

Results

Both patient groups exhibited anti-atherogenic lipid profile except increased serum triglycerides. They had significantly higher plasma Lp-PLA2 and serum TNF-α compared to the controls (P < 0.001). Elevated cIMT was documented in 57% of the thalassemia children and was higher among hepatitis C (HCV) positive patients. Serum ferritin, TNF-α, and plasma Lp-PLA2 levels were significantly higher in patients with premature atherosclerosis. cIMT correlated significantly with serum ferritin, TNF-α, and plasma Lp-PLA2 in both patient groups. Among TM children, serum ferritin had significant positive correlation with serum TNF-α and plasma Lp-PLA2. The elevation of both markers was not related to HCV infection.

Conclusions

Premature atherosclerosis is common among young thalassemia children. Lp-PLA2 and TNF-α are significantly increased in thalassemia children and show strong correlations with cIMT, suggesting that both of them may be appreciated as modulating factors in carotid atherosclerosis pathophysiological process among these children.     

History of myocardial iron loading is a strong risk factor for diabetes mellitus and hypogonadism in adults with β thalassemia major

Endocrinopathies are common complications of transfusional hemosiderosis among patients with β thalassemia major (TM). Previous studies had shown associations between some endocrinopathies and iron overload of the myocardium, liver and/or endocrine organs as assessed by MRI techniques. This retrospective analysis of 92 patients with TM (median age 36 yr) from a tertiary adult thalassemia unit in UK aimed to determine independent risk factors associated with endocrinopathies among these patients. Unlike previous studies, longitudinal data on routine measurements of iron load [worst myocardial and liver T2* values since 1999, worst LIC by MRI‐R2 since 2008 and average 10‐yr serum ferritin (SF)] up to April 2010 together with demographic features and age of initiating chelation were analyzed for associations with endocrinopathies. The most common endocrinopathies in this cohort were hypogonadism (67%) and diabetes mellitus (DM) (41%), and these were independently associated with myocardial T2* <20 ms (P < 0.001 and P = 0.008, respectively) and increased age (P = 0.002 and P = 0.016, respectively). DM and hypogonadism were independently associated with average SF >1250 μg/L (P = 0.003) and >2000 μg/L (P = 0.047), respectively. DM was also associated with initial detection of abnormal myocardial T2* at an older age (30 yr vs. 24 yr, P = 0.039). An abnormal myocardial T2* may therefore portend the development of DM and hypogonadism in patients with TM.     

Limited influence of haptoglobin genotypes on severe malaria in Ghanaian children

Haptoglobin (Hp) polymorphisms in sub-Saharan Africa have been associated with an increased risk of severe malaria. However, available data are inconclusive. We examined the role of Hp polymorphisms in susceptibility to Plasmodium falciparum infection and to severe malaria in northern Ghana. Three groups each of 290 age and sex-matched children with severe malaria, children with asymptomatic P. falciparum infection and aparasitaemic healthy controls were studied. Hp typing was based on PCR. In all children, Hp1-1, Hp2-1, and Hp2-2 occurred in 32.4%, 54.1%, and 13.5%, respectively. The prevalence of the Hp genotypes did not differ significantly between groups. However, Hp2 alleles were least common in healthy children (0.379), more frequent in parasitaemic controls (0.402), and most common in severe malaria patients (0.434; = 3.7; P = 0.06). In matched pair analysis, no Hp genotype increased the risk of severe malaria. However, using Hp1-1 as a reference, children with Hp2-2 exhibited a slightly increased risk of severe malaria (odds ratio, 1.6; P = 0.04). These results indicate that Hp polymorhisms may have a rather limited influence on the development of severe malaria.     

Flow cytometric assessment of circulating platelet and erythrocytes microparticles in young thalassemia major patients: relation to pulmonary hypertension and aortic wall stiffness

Heart disease is the leading cause of mortality and morbidity in β‐thalassemia major (β‐TM). Aggregability of abnormal red cells and membrane‐derived microparticles (MPs) stemming from activated platelets and erythrocytes are responsible for thrombotic risk. We measured platelet and erythrocyte MPs (PMPs and ErMPs) in 60 young β‐TM patients compared with 40 age‐ and sex‐matched healthy controls and assessed their relation to clinicopathological characteristics and aortic elastic properties. Patients were studied stressing on transfusion history, splenectomy, thrombotic events, chelation therapy, hematological and coagulation profiles, flow cytometric measurement of PMPs (CD41b⁺) and ErMPs (glycophorin A⁺) as well as echocardiographic assessment of aortic elastic properties. Aortic stiffness index and pulmonary artery pressure were significantly higher, whereas aortic strain and distensibility were lower in TM patients than controls (P < 0.001). Both PMPs and ErMPs were significantly elevated in TM patients compared with controls, particularly patients with risk of pulmonary hypertension, history of thrombosis, splenectomy or serum ferritin >2500 μg/L (P < 0.001). Compliant patients on chelation therapy had lower MPs levels than non‐compliant patients (P < 0.001). PMPs and ErMPs were positively correlated to markers of hemolysis, serum ferritin, D‐dimer, vWF Ag, and aortic stiffness, whereas negatively correlated to hemoglobin level and aortic distensibility (P < 0.05). We suggest that increased MPs may be implicated in vascular dysfunction, pulmonary hypertension risk, and aortic wall stiffness observed in thalassemia patients. Their quantification could provide utility for early detection of cardiovascular abnormalities and monitoring the biological efficacy of chelation therapy.     

The association of Haptoglobin polymorphism with Crohn's disease in Israel

ObjectivesHaptoglobin is a α²-sialoglycoprotein with hemoglobin binding capacity. Functional differences between the Hp phenotypes with the Hp 1-1 protein being a superior anti-inflammatory to the Hp 2-2 protein have been identified. The aim of our study was to investigate the possible role of Hp polymorphism in the susceptibility to Crohn's disease and its clinical course.MethodsHp phenotypes were determined for 382 Israeli CD patients and 3243 healthy controls. Phenotypic data for all Crohn's disease patients were carefully characterized. Analysis was preformed to evaluate the association between Hp polymorphism and Crohn's disease.ResultsThe frequency of Haptoglobin 1-1 was lower in Crohn's disease patients than in healthy individuals (6.28% vs. 9.28%, P = 0.057). There was no association between Haptoglobin phenotypes and disease location, behavior or extra-intestinal manifestations. No association was found between the Haptoglobin polymorphism and the frequency of the three Crohn's disease associated NOD2 mutations examined.ConclusionsWe found a borderline significant decrease of the Haptoglobin 1-1 phenotype in Israeli Crohn's disease patients compared to healthy controls. Our findings may support the importance of inflammation in Crohn's disease pathogenesis and the protective function of Haptoglobin 1-1 in the susceptibility for Crohn's disease.     

Individuals Homozygous for the H63D Mutation Have Significantly Elevated Iron Indexes

Our objective was to assess the iron indexes of patients with one or more mutations of the HFE gene with a specific interest in studying the effect of the H63D/H63D genotype. Eight hundred twenty subjects who underwent HFE mutational testing for C282Y and H63D mutations were retrospectively identified. Data collected included age, gender, HFE genotype, and values for serum ferritin, iron saturation, aspartate aminotransferase (AST), and alanine aminotransferase (ALT). Compared to the Wild/Wild genotype (0.34 ± 0.17), genotypes H63D/C282Y (0.44 ± 0.14 P < 0.01), H63D/H63D (0.51 ± 0.21 P < 0.01), and C282Y/C282Y (0.64 ± 0.20 P < 0.01) had significantly higher transferrin saturation levels and were independent predictors of higher iron saturation in multivariate regression analysis. Compared to the Wild/Wild genotype, no abnormal HFE genotypes had significantly higher ferritin levels, although the genotype H63D/H63D was an independent predictor of higher serum ferritin (P = 0.02) in regression analysis. There was no significant difference in the proportion of patients with abnormally elevated AST (P = 0.64) or ALT (P = 0.80) between groups. H63D homozygotes have elevated transferrin saturation compared to the Wild genotype, comparable to that of C282Y homozygotes and compound heterozygotes. The clinical significance of this finding is unclear but warrants further study.     

Anthropometric measurements in children having transfusion-dependent beta thalassemia

Objectives: The aim of this study was to determine the anthropometric measurements in transfusion-dependent β-thalassemia children in Pakistan. The secondary aim was to correlate serum ferritin with the physical growth.

Methods: We enrolled 367 children (aged 5–17 years) with transfusion-dependent beta-thalassemia major in the study. Anthropometric measurements, serum ferritin levels, and pre-transfusion hemoglobin levels were measured. Serum ferritin was correlated with the height z-score for age.

Results: Laboratory evaluation showed that patients had significantly low mean pre-transfusion hemoglobin of 7.66?±?1.34?g/dl (range 2.5–10.5) and high median (Q3–Q1) serum ferritin of 5012?ng/ml (6829–3532). The median (Q3–Q1) height-for-age z-score of children was low at ?2.69 and (?1.46 to ?3.80) and 65.4% children had stunted growth (height for age z-score z-score and serum ferritin levels (p?Conclusions: The study showed that children with beta thalassemia major had delayed physical growth possibly secondary to iron overload. Effective and early iron chelation is needed for preventing growth failure in transfusion-dependent beta thalassemia.     

Improved carotid intima-media thickness-induced high-intensity interval training associated with decreased serum levels of Dkk-1 and sclerostin in type 2 diabetes

AimsCarotid intima-media thickness (cIMT) is a validated surrogate marker of atherosclerosis. Dickkopf-1 (Dkk-1) and sclerostin modulate wingless signaling, which is involved in atherosclerosis. The purpose of this study was to investigate whether 12 weeks of high-intensity interval training (HIIT) would improve cIMT and serum Dkk-1 and sclerostin levels in patients with type 2 diabetes.MethodsSeventy-four sedentary patients with type 2 diabetes were randomly divided into HIIT and control groups. The HIIT group intervention was 6 intervals (4 min) at 85%–90% HR_max separated by 3 min at 45%–50% HR_max in 3 sessions/week for 12 weeks. Before and after the intervention, cIMT, artery diameter and wall/lm ratio were recorded with high-resolution ultrasound. Serum sclerostin and Dkk-1 were measured by enzyme-linked immunosorbent assay (ELISA).ResultscIMT decreased significantly in the HIIT group (0.83 ± 0.17 baseline, 0.71 ± 0.14 follow-up) compared to the control group (0.84 ± 0.20 baseline, 0.85 ± 0.19 follow-up) (P < .05). Dkk-1 and sclerostin decreased significantly after 12 weeks of HIIT (P < .01). In addition, VO_2peak was increased in the HIIT group than the control group (by 6.2 mL/kg/min) (P < .05). There was a positive correlation between percent changes in cIMT and percent changes in Dkk-1 and sclerostin (both P < .01). Additionally, there were a negative correlation between percent changes VO2peak and cIMT (r = − 0.740, P = .003), Dkk-1 (r = − 0.844, P < .001) and sclerostin (r = − 0.575, P = .001) in HIIT group.ConclusionOur results indicate that HIIT decreases cIMT, serum levels of Dkk-1 and sclerostin and improves VO_2peak in patients with type 2 diabetes.     

Haptoglobin polymorphism and diabetic retinopathy in Brazilian patients

Haptoglobin (Hp) is an acute phase protein with antioxidant and immunomodulatory properties. Three main genotypes/phenotypes (Hp1-1, Hp2-1 and Hp2-2) show distinct efficiencies in these activities and have been associated with susceptibility and outcome in several diseases, including diabetes mellitus (DM). It has been suggested that Hp polymorphism may influence the development of retinopathy, an important microvascular complication in DM. In order to investigate this association in a Brazilian population, we determined the Hp genotypes of 317 diabetic patients with at least 10 years of disease. The patients were classified as DM-type 1 and 2, with and without diabetic retinopathy (DR). The Hp genotype frequencies of the different patient groups and of a control group consisting of 142 healthy individuals who had previously been studied were compared. No significant differences were observed for the three Hp genotypes. Hemoglobin A1c levels, systolic blood pressure (SBP), diastolic blood pressure (DBP) and duration of diabetes, which are potential risk factors for DR, were also compared. Again no significant differences were observed for the three Hp genotypes. Thus, we conclude that this polymorphism is not associated with the presence of DR in the Brazilian population studied here.     

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

Recently, complications in patients with nontransfusion‐dependent thalassemia (NTDT), in particular those with β‐thalassemia intermedia (β‐TI), were found to be significantly different from those in patients with transfusion dependent thalassemia (TDT), mainly β‐thalassemia major (β–TM). However, this information is rather limited in other forms of NTDT. In this prospective study, adult Thai NTDT patients were interviewed and clinically evaluated for thalassemia related complications. Fifty‐seven NTDT patients (age 18‐74 years), 59.6% Hb E/β‐thalassemia and 40.4% Hb H disease, were recruited; 26.4% were splenectomized. The most common complications were gallstones (68.4%), osteoporosis (26.3%), and pulmonary hypertension (15.8%). Splenectomy was associated with higher rate of gallstones and serious infection (P = .001 and .052, respectively), consistent with a multivariate analysis (RR = 9.5, P = .044, and RR = 15.1, P = .043, respectively). In addition, a higher hemoglobin level was inversely associated with gallstones in both univariate and multivariate analyses (P = .01 and .022, respectively). Serum ferritin was associated with abnormal liver function (P = .002). In contrast to the previous study, the prevalence of thrombosis was less common in our population (1.7%), probably due to differences in transfusion therapy, ethnicity, and underlying genotypes. For the first time, this prospective study provided the current prevalence of NTDT related complications in a Southeast Asian population with a different underlying genetic basis compared with previous studies. Although individual prevalence of each complication might differ from other studies, several important clinical factors such as splenectomy, degree of anemia, and iron overload seem to be determining risks of developing these complications consistently across different ethnicities.     

Haptoglobin polymorphism and peripheral arterial occlusive disease.

Haptoglobin (Hp) 2-2 phenotype is a genetic risk factor in coronary atherosclerosis. In this study, haptoglobin phenotypes were determined in 141 patients with peripheral arterial occlusive disease (PAOD) and compared to a reference population (n = 1000). The relative Hp1 allele frequency was decreased among PAOD patients (0.294 vs. 0.403 for the reference population, P < 0.01) due to an overrepresentation of the Hp 2-2 phenotype (50%, odds ratio 1.82 (95% C.I. 1.28-2.60), P < 0.001). This finding was even more pronounced in non-diabetic and in non-smoking PAOD patients (Hp1 allele frequencies: 0.265 and 0.228, respectively). Serum lipids, inflammatory parameters, and blood pressure levels were comparable among the Hp phenotypes, but serum levels of the antioxidant vitamin C were lower in Hp 2-2 patients than in patients with another phenotype (P < 0.05). In PAOD patients with severe atherosclerotic lesions, maximal walking distance of patients carrying a Hp 2-2 phenotype (225-525 m) exceeded that of other Hp phenotypes (50-242 m) (interquartile ranges) (P < 0.05). The findings demonstrate that, despite an increased risk for developing PAOD, the Hp 2-2 phenotype is associated with a longer maximal walking distance which might be attributed to the earlier reported in vitro angiogenic properties of the Hp 2-2 molecule.     

Glutathione S-transferase gene deletions and their effect on iron status in HbE/β thalassemia patients

Iron overload and oxidative stress are main pathophysiological features of HbE/β thalassemia patients. Glutathione S-transferase genes (GSTT1 and GSTM1) are well known detoxification agents, and any mutation in the gene is known to cause oxidative damage. This study was aimed to compare the prevalence of GST deletions in 240 HbE/β thalassemia patients with 100 controls and to determine role of deletions on iron overload. We observed significantly higher frequency of GSTT1 (P = 0.001) and GSTT1/GSTM1 (P = 0.03) in comparison to controls. Patients who had null genotype for both the alleles, i.e., GSTT1/GSTM1 had significantly higher levels of serum iron (P = 0.007) and serum ferritin (P = 0.001) than patients with normal genotype for GST deletions. This is the first study to prove the role of GST gene deletions with iron overload in HbE/β thalassemia.     

Pattern of iron chelation therapy in Egyptian beta thalassemic patients: Mansoura University Children's Hospital experience

Background: The simultaneous use of deferoxamine (DFO) and deferiprone (DFP) has an additive effect in iron excretion in transfusion-dependent thalassemic patients.

Aim of the work: To evaluate the efficacy and safety of a prospective alternating therapy with DFO and DFP in patients with β-thalassemia major (TM) and increased serum ferritin with DFO monotherapy alone.

Patient and methods: Sixty patients with β-TM (mean age ± SD, 13.05 ± 6.1, range 10–20 years) with iron overload (serum ferritin > 2000 ng/ml) were studied. They received DFO at a daily dose of 40 mg/kg/day for 5–7 nights/week for the past several years. These patients were randomly assigned either to continue treatment with DFO alone (DFO group, n = 30) or prospectively receive additional alternating therapy with DFP at 75 mg/kg/day for 4 days/week and DFO for the other 2 days/week (alternating therapy group, n = 30). The efficacy of both groups was assessed by measurements of serum ferritin, echocardiography, and 24 h urine iron excretion (UIE) levels throughout 1 year follow-up.

Results: In the 60 evaluable patients, the mean serum ferritin (± SD) fell dramatically from 4500 (± 1250) ng/ml at the start of the study to 1250 (± 750) ng/ml (alternate therapy group; P < 0.001) at the end of the study. There was also a significant improvement in the myocardial function as assessed by the ejection fraction (P < 0.002) and fractional shortening (P < 0.01) in those patients on alternate therapy for 1 year. Their mean urinary iron excretion elevated from 0.41 ± 0.27 to 0.76 ± 0.49 mg/kg/24 h (P < 0.003). There was a significant difference between both groups as regard the studied parameters at the end of the study. Whereas, there was no statistical difference as regard the studied parameters at the start and the end of the study in the DFO group. No significant adverse effects had occurred in both groups that necessitated withdrawal from the study.

Conclusions: β-Thalassemic major patients with transfusional iron overload can be safely and effectively treated with an alternate therapy of DFO/DFP with a progressive fall in the mean serum ferritin and significant improvement of myocardial performance.     

Hepatic iron stores and plasma ferritin concentration in patients with sickle cell anemia and thalassemia major

To examine the relationship between hepatic iron stores and plasma ferritin concentration in individuals treated with red cell transfusion and iron chelation therapy, 37 patients with sickle cell anemia and 74 patients with thalassemia major were studied. In each patient, hepatic iron stores were measured by an independently validated noninvasive magnetic method, and plasma ferritin was determined by immunoassay. The correlation between hepatic iron and plasma ferritin was significant both in patients with sickle cell anemia (R = 0.75, P < 0.0001) and in those with thalassemia major (R = 0.76, P < 0.0001). Regression analysis showed no significant difference between the two groups in the linear relationships between hepatic iron stores and plasma ferritin. Considering all 111 transfused patients as a group, the coefficient of correlation between hepatic iron stores and plasma ferritin was highly significant (R = 0.76, P < 0.0001). Regression analysis found that variation in body iron stores, as assessed by magnetic determinations of hepatic iron, accounted for only ～57% of the variation in plasma ferritin, suggesting that the remainder was the result of other factors, such as hemolysis, ineffective erythropoiesis, ascorbate deficiency, inflammation, and liver disease. The 95% prediction intervals for hepatic iron concentration, given the plasma ferritin, were so broad as to make a single determination of plasma ferritin an unreliable predictor of body iron stores. Variability resulting from factors other than iron status limits the clinical usefulness of the plasma ferritin concentration as a predictor of body iron stores. © 1993 Wiley-Liss, Inc.     

Association of haptoglobin levels with age, parasite density, and haptoglobin genotype in a malaria-endemic area of Gabon

Haptoglobin (Hp) levels were investigated in relation to host genotype in a malaria-endemic area in Gabon. A cross-sectional study of 1-12-year-old children was conducted in the rainy season, a period of high malaria transmission, to examine this relationship. Variables that influenced Hp levels were Hp genotype, location, and age interacting with parasite density. At low parasite densities, there was a negative correlation between Hp levels and age. At higher densities, there was a positive correlation with age. This suggests that in the presence of greater parasite-induced hemolysis, older children are capable of increased production of Hp. Sickle cell trait and ABO blood group was not associated with Hp levels in this population.     

Serum ferritin,transferrin and metabolic syndrome are risk factors for subclinical atherosclerosis in Egyptian women with systemic lupus erythematosus (SLE)

Aim of the work

This work aimed to measure serum ferritin and transferrin levels and to study the presence of metabolic syndrome (MetS) in Egyptian systemic lupus erythematosus (SLE) females and to correlate them with disease activity, damage, clinical status and subclinical atherosclerosis.

Evaluation of cardiac and hepatic iron overload in thalassemia major patients with T2* magnetic resonance imaging

Objectives: Recent advancements have promoted the use of T2* magnetic resonance imaging (MRI) in the non-invasive detection of iron overload in various organs for thalassemia major patients. This study aims to determine the iron load in the heart and liver of patients with thalassemia major using T2* MRI and to evaluate its correlation with serum ferritin level and iron chelation therapy.

Methods: This cross-sectional study included 162 subjects diagnosed with thalassemia major, who were classified into acceptable, mild, moderate, or severe cardiac and hepatic iron overload following their T2* MRI results, respectively, and these were correlated to their serum ferritin levels and iron chelation therapy.

Results: The study found that 85.2% of the subjects had normal cardiac iron stores. In contrast, 70.4% of the subjects had severe liver iron overload. A significant but weak correlation (r?=??0.28) was found between cardiac T2* MRI and serum ferritin, and a slightly more significant correlation (r?=?0.37) was found between liver iron concentration (LIC) and serum ferritin.

Discussion: The findings of this study are consistent with several other studies, which show that patients generally manifest with liver iron overload prior to cardiac iron overload. Moreover, iron accumulation demonstrated by T2* MRI results also show a significant correlation to serum ferritin levels.

Conclusion: This is the first study of its kind conducted in Indonesia, which supports the fact that T2* MRI is undoubtedly valuable in the early detection of cardiac and hepatic iron overload in thalassemia major patients.     

Is Pica under-reported in children with sickle cell disease? A pilot study in a Belgian cohort

Abstract

Background

For centuries, writers have recorded their observations on pica. Nevertheless the association of pica with sickle cell disease (SCD) was poorly documented.

Methods

Cross-sectional evaluation performed on SCD children and caregivers attending the outpatient clinic who were invited to complete questionnaires assessing behavior of pica.

Results

Out of 55 sickle cell children, 31(56.4%) reported practicing pica regularly. Substances ingested by patients covered a broad spectrum. Compared with the non-pica group, subjects who reported pica were younger and had lower hemoglobin (8.3 g/dl (7.6–9.7) vs. 9.1 g/dl (7.9–10.5): P < 0.01). The level of ferritin, zinc, copper, and lead was similar between the pica and non-pica groups (P > 0.05).

Discussion

In this series, there are many substances consumed by SCD children and adolescents, and we did not find an occurrence of similar substances among this select group. Pica children were younger and more anemic than non-pica patients.

Conclusion

This study suggests that pica remains an unknown and under-reported clinical problem in children with SCD and seems to be related to the severity of anemia. The next step of this project aims to clarify causal mechanisms for pica and its association with SCD in a larger population.     

Effect of HBB genotype on survival in a cohort of transfusion-dependent thalassemia patients in Cyprus

Initiation of regular transfusion in transfusion-dependent thalassemia (TDT) is based on the assessment of clinical phenotype. Pathogenic HBB variants causing β-thalassemia are important determinants of phenotype and could be used to aid decision-making. We investigated the association of HBB genotype with survival in a cohort study in the four thalassemia centers in Cyprus. HBB genotype was classified as severe (β0/β0 or β+/β0), moderate (β+/β+), or mild (β0/β++ or β+/β++). Risk factors for mortality were evaluated using multivariate Cox proportional- hazards regression. Of the 537 subjects who were followed for a total of 20,963 person-years, 80.4% (95% confidence interval [95% CI]: 76.4-84.7) survived to 50 years of age with increasing rates of liver-, infectionand malignancy-related deaths observed during recent follow-up. We evaluated non-modifiable risk factors and found worse outcomes associated with male sex (hazard ratio 1.9, 95% CI: 1.1-3.0, P=0.01) and milder genotype (hazard ratio 1.6, 95% CI: 1.1-2.3, P=0.02). The effect of genotype was confirmed in a second model, which included treatment effects. Patients with a milder genotype initiated transfusion significantly later and had reduced blood requirements compared to those with moderate or severe genotypes, although pre-transfusion hemoglobin levels did not differ between genotypes. Our results suggest that early treatment decisions to delay transfusion and different long-term treatment strategies in individuals with milder genotypes have led to adverse longterm effects of under-treated thalassemia and worse survival. We propose that HBB genotype determination and use of this information to aid in decision-making can improve long-term outcomes of thalassemia patients.     

Haptoglobin type neither influences iron accumulation in normal subjects nor predicts clinical presentation in HFE C282Y haemochromatosis: phenotype and genotype analysis

In the UK, 90% of patients with hereditary haemochromatosis (HH) are homozygous for HFE C282Y, as are one in 150 people in the general population. However, only a minority of these will develop clinical haemochromatosis. Iron loss modifies iron accumulation but so may other genetic factors. Haptoglobin (Hp) exists as three major types (Hp 1-1, Hp 2-1 or Hp 2-2) and binds free plasma haemoglobin. In men, Hp 2-2 has been shown to be associated with increased macrophage iron accumulation and serum ferritin concentration. Furthermore, the frequency of Hp 2-2 was shown to be increased in patients with HH. We determined Hp types by phenotyping and genotyping 265 blood donor control subjects and 173 subjects who were homozygous for HFE C282Y. The latter group included 66 blood donors lacking clinical features suggestive of haemochromatosis and without a known family history, and 68 patients presenting clinically with haemochromatosis. Hp 2-2 frequencies did not differ in control subjects and C282Y homozygotes. Hp 2-2 was not a risk factor for disease development in HH. To investigate the relationship between iron accumulation and haptoglobin type, we determined transferrin saturation and serum ferritin concentration in 192 male, first-time blood donors aged 20-40 years who lacked both HFE C282Y and H63D. Transferrin saturation and serum ferritin concentrations did not vary with Hp type.