Consequences and costs of noncompliance with iron chelation therapy in patients with transfusion-dependent thalassemia: a literature review

Challenges of adherence and persistence with iron chelation therapy

Due to advances in medical sciences, many chronic diseases that formerly resulted in early death can now be effectively managed with long-term treatment regimens. Patients with potentially fatal anemias, for example, can be treated with ongoing blood transfusions and iron chelation therapy. Ensuring adherence and persistence is challenging, as the benefits of therapy are not perceived immediately. Poor adherence severely compromises the effectiveness of treatment and, therefore, improving compliance in terms of quality of life and health economics is critical. Although adherence to chelation therapy is generally poor, the availability of oral iron chelators may help to improve patient compliance. For chronic conditions such as thalassemia major, even when oral chelation therapy is available, support by an integrated team including a clinical psychologist and nurse specialist working with the treatment center is recommended to achieve optimal results.

Management of transfusional iron overload - differential properties and efficacy of iron chelating agents

Regular red cell transfusion therapy ameliorates disease-related morbidity and can be lifesaving in patients with various hematological disorders. Transfusion therapy, however, causes progressive iron loading, which, if untreated, results in endocrinopathies, cardiac arrhythmias and congestive heart failure, hepatic fibrosis, and premature death. Iron chelation therapy is used to prevent iron loading, remove excess accumulated iron, detoxify iron, and reverse some of the iron-related complications. Three chelators have undergone extensive testing to date: deferoxamine, deferasirox, and deferiprone (although the latter drug is not currently licensed for use in North America where it is available only through compassionate use programs and research protocols). These chelators differ in their modes of administration, pharmacokinetics, efficacy with regard to organ-specific iron removal, and adverse-effect profiles. These differential properties influence acceptability, tolerability and adherence to therapy, and, ultimately, the effectiveness of treatment. Chelation therapy, therefore, must be individualized, taking into account patient preferences, toxicities, ongoing transfusional iron intake, and the degree of cardiac and hepatic iron loading.

Self-reported level of and factors influencing the compliance to desferrioxamine therapy in multitransfused thalassaemias

AIM

To analyse the self-reported degree of and factors influencing the compliance to desferrioxamine (DFO) therapy in children with transfusion-dependent thalassaemia major in Malaysia.

METHODS

A cross-sectional study was conducted on all children with thalassaemia major on DFO attending Likas Hospital, Sabah, in September 2008. Patients or carer-providers were interviewed to report on the degree of compliance as either highly (administering >90% of DFO), moderately (51-90%), poorly (1%-50%) or non-compliant (0%) to DFO in the preceding month. The latest serum ferritin levels were noted.

RESULTS

The median (range) age at first blood transfusion of these 139 (73 males, median (range) age at interview: 9.0 years (2-16 years)) patients were 1.0 year (2 months to 10 years). The median (range) duration of regular DFO therapy was 2 years (2 months to 10 years). Forty-three (31%) of the patients reported themselves to be highly compliant, 70 (50%) moderately and 26 (19%) poorly or non-compliant. Multivariate analysis showed that a lower family income negatively affected the degree of compliance, while family support positively affected the degree of compliance to DFO. No correlation existed between self-reported degree of compliance and latest serum ferritin level (6444 ± µmol/L; P = 0.186).

CONCLUSION

The self-reported compliance to DFO therapy was moderate in this cohort of patients with thalassaemia major in Malaysia. The serum ferritin level was high, possibly because of the relatively short duration of DFO therapy and compliance. Oral iron chelator should be considered to improve the compliance to iron chelation.

Synthetic and natural iron chelators: therapeutic potential and clinical use

Iron-chelation therapy has its origins in the treatment of iron-overload syndromes. For many years, the standard for this purpose has been deferoxamine. Recently, considerable progress has been made in identifying synthetic chelators with improved pharmacologic properties relative to deferoxamine. Most notable are deferasirox (Exjade(®)) and deferiprone (Ferriprox(®)), which are now available clinically. In addition to treatment of iron overload, there is an emerging role for iron chelators in the treatment of diseases characterized by oxidative stress, including cardiovascular disease, atherosclerosis, neurodegenerative diseases and cancer. While iron is not regarded as the underlying cause of these diseases, it does play an important role in disease progression, either through promotion of cellular growth and proliferation or through participation in redox reactions that catalyze the formation of reactive oxygen species and increase oxidative stress. Thus, iron chelators may be of therapeutic benefit in many of these conditions. Phytochemicals, many of which bind iron, may also owe some of their beneficial properties to iron chelation. This review will focus on the advances in iron-chelation therapy for the treatment of iron-overload disease and cancer, as well as neurodegenerative and chronic inflammatory diseases. Established and novel iron chelators will be discussed, as well as the emerging role of dietary plant polyphenols that effectively modulate iron biochemistry.

Iron chelation adherence to deferoxamine and deferasirox in thalassemia

The Thalassemia Clinical Research Network collected adherence information from 79 patients on deferoxamine and 186 on deferasirox from 2007 to 2009. Chelation adherence was defined as percent of doses administered in the last 4 weeks (patient report) out of those prescribed(chart review). Chelation history since 2002 was available for 97 patients currently on deferoxamine and 217 on deferasirox, with crude estimates of adherence from chart review. Self-reported adherence to both deferoxamine and deferasirox were quite high, with slightly higher adherence to the oral chelator (97 vs. 92%). Ninety percent of patients on deferasirox reported at least 90% adherence, compared with 75% of patients on deferoxamine. Adherence to both chelators was highest in children, followed by adolescents and older adults.Predictors of lower deferoxamine adherence were smoking in the past year, problems sticking themselves (adults only), problems wearing their pump, and fewer transfusions in the past year. Predictors of lower deferasirox adherence were bodily pain and depression. Switching chelators resulted in increased adherence, regardless of the direction of the switch, although switching from deferoxamine to deferasirox was far more common. As adherence to deferoxamine is higher than previously reported, it appears beneficial for patients to have a choice in chelators.

Bayesian estimates of the prevalence of β-thalassemia trait in voluntary blood donors of central India: a survey

Early detection of β-thalassemia (β-thal) trait is important. Voluntary blood donors represent an important group who are accessible and cooperative for this purpose. However, the usefulness of this population in β-thal trait detection programs has not been studied in India. We conducted a hematological survey of 5,045 blood donors who visited the Bhopal Memorial Hospital & Research Centre, Bhopal in central India. Using robust Bayesian methods, we estimated the prevalence of β-thal trait. The overall prevalence of β-thal trait in the study population was 9.59% [95% confidence interval (95% CI) 8.78-10.4%]. The prevalence of β-thal trait varied across the states of origin and within the state of Madhya Pradesh. We observed a cline effect for β-thal trait prevalence in relation to the latitude (p = 0.024). We conclude that blood donors offer an attractive adjunct to β-thal trait detection in national programs. Our study also offers insights into the β-thal trait gene flow and migration in India.

Induction of human fetal hemoglobin via the NRF2 antioxidant response signaling pathway

Although hematopoietic stem cell transplantation and gene therapy have the potential to cure β-thalassemia and sickle cell disease, they are not currently available to most people with these diseases. In the near term, pharmacologic induction of fetal hemoglobin (HbF) may offer the best possibility for safe, effective, and widely available therapy. In an effort to define new pathways for targeted drug development for HbF induction, we evaluated the nuclear factor erythroid 2-related factor 2 (NRF2) antioxidant response element signaling pathway. We found that 3 well-known activators of this pathway increased γ-globin mRNA at nontoxic doses in K562 cells. Tert-butylhydroquinone (tBHQ), the most active of these compounds, increased cellular levels and nuclear translocation of NRF2 and binding of NRF2 to the γ-globin promoter. siRNA knockdown of NRF2 inhibited γ-globin induction by tBHQ. When tested in human primary erythroid cells, tBHQ induced NRF2 binding to the γ-globin promoter, increased γ-globin mRNA and HbF, and suppressed β-globin mRNA and HbA, resulting in a > 3-fold increase in the percentage of HbF. These results suggest that drugs that activate the NRF2/antioxidant response element signaling pathway have the potential to induce therapeutic levels of HbF in people with β-hemoglobinopathies.

Which psychosocial factors are related to chelation adherence in thalassemia? A systematic review

Good adherence to iron chelation therapy in thalassemia is crucial. Although there is evidence that adherence is related to regimen factors, there has been less emphasis on the relationship between psychosocial (psychological, demographic and social) factors and adherence. We present a systematic review of psychosocial correlates of chelation adherence in thalassemia. Nine studies met the inclusion criteria. Information was extracted regarding the study characteristics and the relationship between psychosocial factors and chelation adherence. Methodological quality was rated. The studies took place in a range of countries, were mostly cross sectional in design, and examined adherence to deferoxamine (DFO) only. Sample sizes ranged from 15 to 1573. A variety of psychosocial variables were examined. Definitions of adherence varied between studies and non adherence rates were also variable (9 to 66%). Older age was consistently associated with lower levels of chelation adherence. There were few other consistent findings. The methodological quality of studies was variable. There is a need for more methodologically sophisticated and theoretically informed studies on psychosocial correlates of chelation adherence. We offer specific suggestions.

Iron-chelating therapy for transfusional iron overload

A 16-year-old boy with sickle cell anemia undergoes routine screening with transcranial Doppler ultrasonography to assess the risk of stroke. This examination shows an abnormally elevated blood-flow velocity in the middle cerebral artery. The hemoglobin level is 7.2 g per deciliter, the reticulocyte count is 12.5%, and the fetal hemoglobin level is 8.0%. Long-term treatment with red-cell transfusion is initiated to prevent stroke. A hematologist recommends prophylactic iron-chelating therapy.

Safety and efficacy of high dose intravenous desferrioxamine for reduction of iron overload in sickle cell disease

BACKGROUND

Patients with sickle cell disease (SCD) receiving chronic blood transfusions are at risk of developing iron overload and organ toxicity. Chelation therapy with either subcutaneous (SQ) desferrioxamine (DFO) or oral deferasirox is effective in preventing and reducing iron overload but poses significant challenges with patient compliance. Intravenous (IV) infusions of high dose DFO have been utilized in non-compliant patients with heavy iron overload in small case series.

PROCEDURE

We review our experience of high dose IV DFO in 27 patients with SCD who had significant iron overload and were noncompliant with subcutaneous (SQ) DFO. All patients were treated in-hospital with DFO 15 mg/kg/hr IV for 48 hr every 2-4 weeks with a mean duration of 19.6 months.

RESULTS

We observed a significant decrease in liver iron burden with high dose intermittent IV DFO. Histological examination of liver biopsies revealed a decrease in the grade of liver iron storage. Also there was significant improvement in liver enzymes (ALT, AST) after high dose IV DFO. No audiologic or ophthalmologic toxicity or acute or chronic pulmonary complications were observed.

CONCLUSIONS

In our cohort of patients with SCD we observed a significant decrease in liver iron burden with high dose IV DFO. Our patients tolerated the therapy well without any major toxicity. This regimen is safe and may be an option for poorly compliant patients with significant iron overload.

Oral chelation: should it be used with young children?

Deferasirox, the only oral iron chelator approved in the US and Canada, achieved a pediatric label indication down to 2 years of age. FDA-mandated post-marketing safety surveillance in children under age 6 is ongoing. We wish to raise a non-safety-related concern with deferasirox chelation in very young children (2-5 years old). Specifically, the circumstances required for reliable daily ingestion of deferasirox do not mesh well with the developmental characteristics common in young children, which may limit adherence and cause parental distress. We review developmental challenges associated with oral chelation in this age group and provide suggestions to improve adherence in this population.

Socio-psychological impact of infused iron chelation therapy with deferoxamine in metropolitan France: ISOSFER study results

Deferoxamine (DFO) is an iron chelator used to treat iron overload in patients receiving chronic blood transfusions, and is usually administered as overnight subcutaneous infusions. ISOSFER was a prospective, observational, cross-sectional study conducted in metropolitan France that evaluated patient characteristics, quality of life (QoL), compliance and patient satisfaction with DFO monotherapy. Of 70 patients with either thalassemia, sickle cell disease or myelodysplastic syndromes, 30% were 'satisfied' or 'very satisfied' with DFO. Patients' SF-36 scores were lower than those of the general French population, and lower among patients with comorbidities and those dissatisfied with treatment. Although 72% of patients had good compliance to DFO, 57% reported missing at least one infusion in the previous month, and 82% of patients expressed a preference for oral therapy. These results suggest that QoL is severely compromised in patients receiving DFO, and that compliance is not optimal.

Hematopoietic stem cell transplantation for hemoglobinopathies: current practice and emerging trends

Despite improvements in the management of thalassemia major and sickle cell disease, treatment complications are frequent and life expectancy remains diminished for these patients. Hematopoietic stem cell transplantation (HSCT) is the only curative option currently available. Existing results for HSCT in patients with hemoglobinopathy are excellent and still improving. New conditioning regimens are being used to reduce treatment-related toxicity and new donor pools accessed to increase the number of patients who can undergo HSCT.

Economic burden of beta-thalassemia/Hb E and beta-thalassemia major in Thai children

Background

Hemoglobin E beta-thalassemia (β-thalassemia/Hb E) has a variable severity, and the cost of treatment has not been well studied. The aim of this study was to analyze the societal cost of caring for children with β-thalassemias in Thailand. The study was designed as a prevalence-based cost-of-illness analysis in a societal perspective. Medical records from three public hospitals of children aged 2-18 years with β-thalassemia/Hb E and homozygous β-thalassemia were reviewed for direct medical cost determination. For direct non-medical cost and indirect cost, a family member was interviewed.

Findings

It was found that 201 patients with β-thalassemia/Hb E (91%) and homozygous β-thalassemia (9%) were recruited for this study. Ninety-two (46%) were severe thalassemia and 109 (54%) were mild to moderate severity. The annual average cost of treatment was US$950; 59% was direct medical cost, 17% direct non-medical cost, and 24% indirect cost. The costs were differentiated by some potential predictors. Significant predictor variables were: hospital, health insurance scheme, blood transfusion pattern, and iron chelation drug use.

Conclusions

The average annual cost per patient was calculated, and the cost model was estimated. These would be applied for national planning, economic evaluation of treatment and prevention interventions, and budget impact analysis.

Clinical consequences of iron overload from chronic red blood cell transfusions, its diagnosis, and its management by chelation therapy

Iron overload from chronic transfusion therapy can be extremely toxic. Excess transfusional iron is deposited in the liver, heart, and other organs as free iron, which can cause organ dysfunction and damage over time. Increased awareness of the risk of iron overload in patients requiring chronic transfusion therapy is needed, and such patients should be screened for hyperferritinemia. Those with serial serum ferritin levels exceeding 1000 ng/mL and a total infused red blood cell volume of 120 mL/kg of body weight or more should be treated with chelation therapy and then monitored to ensure that treatment adequately reduces iron levels.

Sickle cell disease and stroke

Twenty-four percent of sickle cell disease (SCD) patients have a stroke by the age of 45 years. Blood transfusions decrease stroke risk in patients deemed high risk by transcranial Doppler. However, transcranial Doppler has poor specificity, and transfusions are limited by alloimmunization and iron overload. Transfusion withdrawal may be associated with an increased rebound stroke risk. Extended blood typing decreases alloimmunization in SCD but is not universally adopted. Transfusions for thalassemia begun in early childhood are associated with lower rates of alloimmunization than are seen in SCD, suggesting immune tolerance. Optimal oxygen transport efficiency occurs at a relatively low hematocrit for SCD patients because of hyperviscosity. Consequently, exchange rather than simple transfusions are more effective in improving oxygen transport efficiency, but the former are technically more demanding and require more blood units. Although viscosity is of importance in the noncerebral manifestations of SCD, inflammation may play a larger role than viscosity in the development of large-vessel stroke. The future of SCD stroke management lies in the avoidance of transfusion. Hydroxyurea and anti-inflammatory measures may reduce the need for transfusion. Recent genome-wide association studies may provide methods for modulating fetal hemoglobin production enough to attenuate stroke risk and other complications of SCD.

Update on the use of deferasirox in the management of iron overload

Regular blood transfusions as supportive care for patients with chronic anemia inevitably lead to iron overload as humans cannot actively remove excess iron. The cumulative effects of iron overload cause significant morbidity and mortality if not effectively treated with chelation therapy. Based on a comprehensive clinical development program, the once-daily, oral iron chelator deferasirox (Exjade((R))) is approved for the treatment of transfusional iron overload in adult and pediatric patients with various transfusion-dependent anemias, including beta-thalassemia and the myelodysplastic syndromes. Deferasirox dose should be titrated for each individual patient based on transfusional iron intake, current iron burden and whether the goal is to decrease or maintain body iron levels. Doses of >30 mg/kg/day have been shown to be effective with a safety profile consistent with that observed at doses <30 mg/kg/day. Recent data have highlighted the ability of deferasirox to decrease cardiac iron levels and to prevent the accumulation of iron in the heart. The long-term efficacy and safety of deferasirox for up to 5 years of treatment have now been established. The availability of this effective and generally well tolerated oral therapy represents a significant advance in the management of transfusional iron overload.

A time-cost augmented economic evaluation of oral deferasirox versus infusional deferoxamine [corrected] for patients with iron overload in South Korea

OBJECTIVES

This study aims to conduct an economic evaluation of oral deferasirox (DSX) compared with infusional deferoxamine (DFO) in patients with transfusional iron overload.

METHODS

Depending on the methods for measuring time-cost and convenience associated with the mode of administration, either cost-utility analysis or cost-effectiveness analysis was undertaken. The difference in compliance rate between DSX and DFO was applied.

RESULTS

Although the drug cost of DSX was US$124,070 higher than that of DFO (US$96,039 vs. US$220,199), all other costs were lower in patients with DSX than in patients with DFO. In the cost-utility analysis, DSX resulted in US$3197 savings with a gain of 2.63 quality-adjusted life-years per patient. The result of the cost-effectiveness analysis also showed that DSX dominated DFO.

CONCLUSIONS

With a considerable improvement in convenience and injection time rather than efficacy, DSX is considered as a dominant therapy for patients with iron overload.

Adherence to deferasirox in children and adolescents with sickle cell disease during 1-year of therapy

BACKGROUND

Adherence to long-term treatment is challenging. Deferasirox (DFX) is a daily oral iron chelator approved in the United States for transfusional iron overload.

PROCEDURES

Twenty-one subjects with sickle cell disease (mean age 13.8+/-4.2 y) received DFX 20 to 30 mg/kg daily for 1-year while on chronic blood transfusions. Good adherence to DFX was defined as > or =80% intake of prescribed dose. Adherence was assessed by monthly pill counts and calendars, and questionnaires at 1, 3, 6, and 12 months follow-up.

RESULTS

Fifteen of 21 subjects (71%) were adherent to DFX according to self-reports, with 83% of the patients being adherent at 1 month, 89% at 3 months, 65% at 6 months, and 78% at 12 months. We were only able to document continuous good adherence in 43% of patients by pill counts because of poor bottle return. The discrepancy between pill counts and self-reports may be related to over-reporting, with the real adherence being lower. Parental involvement with DFX administration (P=0.03) and age < or =16 years (P=0.0055) correlated with adherence. We could not detect a significant correlation between serum ferritin declines and adherence.

CONCLUSION

Seventy-one percent of patients adhered to DFX according to questionnaire responses but only 43% did according to pill counts. Adherence was poorer in adolescents older than 16 years of age and in patients who had no parental supervision of medications.

Emotional impact in beta-thalassaemia major children following cognitive-behavioural family therapy and quality of life of caregiving mothers

Background

Cognitive-Behavioural Family Therapy (CBFT) can be an effective psychological approach for children with β-thalassaemia major, increasing compliance to treatment, lessening the emotional burden of disease, and improving the quality of life of caregivers.

Design and methods

Twenty-eight β-thalassaemic major children that followed CBFT for one year were compared with twenty-eight age-matched healthy children, focusing particularly on behavioural, mood, and temperamental characteristics as well as compliance with chelation, assessed using the Child Behaviour Checklist (CBCL), Children's Depression Inventory (CDI), Multidimensional Anxiety Scale for Children (MASC), and Emotionality, Activity, Sociability and Shyness Scale (EAS). We also monitored the quality of life of caregiving mothers using the World Health Organization Quality Of Life (WHOQOL-BREF) questionnaire. Data were analysed with non-parametric standard descriptive statistics.

Results

90% of β-Thalassaemic children showed good compliance with chelation therapy; however they had significantly increased somatic complains, physical symptoms and separation panic. Moreover, temperamental assessment revealed high emotionality and poor sociability in treated thalassaemic children and in their mothers. Physical and psychological domains concerning individual's overall perception of quality of life resulted impaired in mothers of β-thalassaemic children.

Conclusion

CBFT can be a valid tool to increase the compliance with chelation therapy in β-thalassaemic children; however, treated children continue to show an important emotional burden; moreover, CBFT therapy seems not to have any positive impact on the quality of life of caregiving mothers, who may therefore need additional psychological support.

Long-term experience with deferasirox (ICL670), a once-daily oral iron chelator, in the treatment of transfusional iron overload

BACKGROUND

Chronic iron overload from frequent blood transfusions to treat patients with severe anaemias leads to significant morbidity and mortality. While deferoxamine, the current standard of care, is an effective iron chelator, it requires subcutaneous infusion for 8-12 h/day, 5-7 days/week. This regimen is problematic and impacts significantly on patients' daily life.

OBJECTIVE

To evaluate the efficacy and tolerability of deferasirox, a once-daily oral iron chelator.

METHOD

To review the available data reported in peer-reviewed journals (using PubMed) and at medical conferences.

RESULTS/CONCLUSIONS

Deferasirox is effective in reducing or maintaining iron burden in patients with transfusion-dependent anaemias. As deferasirox is orally administered, the inconvenience of parenteral administration with deferasirox is avoided. Deferasirox improves patient satisfaction and is expected to improve compliance with iron chelation therapy.

A cell stress signaling model of fetal hemoglobin induction: what doesn't kill red blood cells may make them stronger

A major goal of hemoglobinopathy research is to develop treatments that correct the underlying molecular defects responsible for sickle cell disease and beta-thalassemia. One approach to achieving this goal is the pharmacologic induction of fetal hemoglobin (HbF). This strategy is capable of inhibiting the polymerization of sickle hemoglobin and correcting the globin chain imbalance of beta-thalassemia. Despite this promise, none of the currently available HbF-inducing agents exhibit the combination of efficacy, safety, and convenience of use that would make them applicable to most patients. The recent success of targeted drug therapies for malignant diseases suggests that this approach could be effective for developing optimal HbF-inducing agents. A first step in applying this approach is the identification of specific molecular targets. However, while >70 HbF-inducing agents have been described, neither molecular mechanisms nor target molecules have been definitively verified for any of these compounds. To help focus investigation in this area, we have reviewed known HbF-inducing agents and their proposed mechanisms of action. We find that in many cases, current models inadequately explain key experimental results. By integrating features of the erythropoietic stress model of HbF induction with data from recent intracellular signaling experiments, we have developed a new model that has the potential to explain several findings that are inconsistent with previous models and to unify most HbF-inducing agents under a common mechanism: cell stress signaling. If correct, this or related models could lead to new opportunities for development of targeted therapies for the beta-hemoglobinopathies.

Costs, quality of life, treatment satisfaction and compliance in patients with beta-thalassemia major undergoing iron chelation therapy: the ITHACA study

OBJECTIVES

Iron chelation treatment (ICT) in beta-thalassemia major (beta-TM) patients undergoing blood transfusions can cause low satisfaction, low compliance, with possible negative consequences on treatment success, patients' wellbeing, and costs. The purpose was to estimate the societal burden attributable to beta-TM in terms of direct and indirect costs, health-related quality-of-life (HRQoL), satisfaction and compliance with ICT in patients undergoing transfusions and ICT.

RESEARCH DESIGN AND METHODS

The naturalistic, multicenter, longitudinal Italian-THAlassemia-Cost-&-Outcomes-Assessment (ITHACA) cost-of-illness study was conducted involving patients of any age, on ICT for at least 3 years, who were enrolled at 8 Italian Thalassemia Care Centers. Costs were estimated from the societal perspective, quantified with tariffs, prices, or net earnings valid in 2006.

RESULTS

One-hundred and thirty-seven patients were enrolled (median age = 28.3, 3-48 years, 49.6% male) and retrospectively observed for a median of 11.6 months. Mean direct costs were euro1242/patient/month, 55.5% attributable to ICT, 33.2% attributable to transfusions. Relevant quantity and quality of productivity was lost. Both physical and mental components of HRQoL were compromised. Little difficulties remembering to take ICT and positive satisfaction with the perceived effectiveness of therapy were declared, but not good levels of satisfaction with acceptance, perception of side effects and burden of ICT.

CONCLUSIONS

The management of beta-TM patients undergoing transfusions and ICT is efficacious, although costly, but overall benefits were not always perceived as optimal by patients. Efforts must be focused to improve patients' acceptance and satisfaction with their therapy; this would contribute to a better compliance and hence an increase in treatment effectiveness and patients' overall wellbeing, with expected improved allocation of human and economic resources.

Disparity in the management of iron overload between patients with sickle cell disease and thalassemia who received transfusions

BACKGROUND

Transfusion therapy is frequently used to prevent morbidity in sickle cell disease (SCD), and subsequent iron overload is common. The objective of this study was to evaluate the current standard of care in monitoring iron overload and related complications in patients with SCD compared to thalassemia (Thal).

STUDY DESIGN AND METHODS

A cross-sectional study was conducted at 31 hematology clinics in the United States, Canada, or the United Kingdom. Patients who received transfusions with a mean serum ferritin level of least 2000 ng per mL were eligible. A total of 199 patients with SCD (113 female; 24.9 +/- 13.2 years) and 142 with Thal (66 female; 25.8 +/- 8.1 years) were recruited, and data were collected between 2001 and 2003 by interview and medical record review.

RESULTS

Although both groups were recruited on the basis of significant iron overload, the likelihood of performing a liver biopsy for routine iron monitoring was significantly higher (odds ratio [OR], 3.4; 95% confidence interval [CI], 2.2-5.3) in Thal than SCD. Thal patients were also more likely to be screened for iron-related organ injury including an echocardiograph for cardiomyopathy (OR, 2.6; p < 0.001; 95% CI, 1.6-4.2), alanine aminotransferase for liver function (OR, 8.3; CI, 1.05-64.4), and thyroid-stimulating hormone for hypothyroidism (OR, 12.3; CI, 7.0-21.5). For adult SCD patients, those maintained on simple transfusion with a serum ferritin level of greater than 2500 ng per mL were the least likely to have a liver biopsy (p < 0.03).

CONCLUSIONS

These data highlight the unsystematic monitoring of iron and related organ injury in SCD. Until the relationship between iron and related comorbidities is better understood, routine monitoring of iron overload in SCD patients who receive transfusions should be considered a standard part of clinical care.