β-Thalassemia in Iran: Things Everyone Needs to Know About This Disease

The Spectrum of HBB Mutations among 2315 Beta Thalassemia Patients of a Reference Clinic in Tehran-Iran

Beta Thalassemia is the most prevalent and well-studied single gene disorder in Iran. Here, we investigated the spectrum of HBB gene mutations, identified among 2315 patients, referred to a reference thalassemia clinic in Tehran, on the basis of suspicion to thalassemia major or intermedia. The patients were homozygous or compound heterozygous for HBB mutations, and were referred from various Iranian provinces, during 15 years (2001- 2016). The HBB mutations were classified based on their frequency, and the result was compared to a meta-analysis of 14,293 beta thalassemia cases in the Iranian population, within the same time period. The mutation spectrum in this study contained 43 HBB mutations, compared to the 90, presented by the meta-analysis. Similar to the meta-analysis, IVSII-1 (G > A) and IVSI-5 (G > C) were the most common mutations in this study. These two comprised 62.40% of the total HBB mutant alleles in the studied population, comparable to 51.92% of that in the meta-analysis. IVSII-1 (G > A) and IVSI-5 (G > C), followed by 17 other mutations that had frequencies ranging from 0.15% to 5.44%, were among the 20 common HBB mutations in Iran and neighboring countries, according to the meta-analysis. This study provided further evidence to support the spectrum of the most common HBB mutations in the Iranian population.

Complications in patients with transfusion dependent thalassemia: A descriptive cross-sectional study

Background and Aims

One of the most common hemoglobinopathies globally related to blood transfusion and iron overload in the body is thalassemia syndrome. Increasing ferritin levels can cause severe damage to the patient's body organs. This study aims to evaluate the complications of iron overload on vital body organs in patients with transfusion-dependent beta-thalassemia.

Methods

This descriptive cross-sectional study was performed in Iran University of Medical Sciences Hospitals on patients with a beta-thalassemia major with frequent blood transfusions. To evaluate the effect of iron overload on vital body organs, hematologic and blood analysis, echocardiography with measurement of pulmonary artery pressure (PAP) and ejection fraction (EF) tests, bone densitometry, and audiometric tests were performed for all patients.

Results

Of the 1010 patients participating in this study, 497 (49%) were males, 513 were (51%) females aged 5-74 years, and the majority of participants (85%) were over 20 years old. This study demonstrated that increasing ferritin levels had no notable correlation with sex, cholesterol, low-density lipoprotein, parathyroid hormone, T4, and aspartate aminotransferase. However, elevating ferritin levels had significant correlations with increasing triglyceride, phosphorus, thyroid stimulating hormone, alkaline phosphatase, alanine transaminase, and PAP levels, age, hearing disorders, splenectomy, osteoporosis, and decreasing high-density lipoprotein, body mass index, calcium, and EF levels.

Conclusion

Improvement in beta-thalassemia patients' survival and quality of life can be due to multidisciplinary care in a comprehensive unit through regular follow-up and early complication detection.

Epidemiology of clinically significant forms of alpha- and beta-thalassemia: A global map of evidence and gaps

This systematic literature review assessed the global prevalence and birth prevalence of clinically significant forms of alpha- and beta-thalassemia. Embase, MEDLINE, and the Cochrane Library were searched for observational studies published January 1, 2000, to September 21, 2021. Of 2093 unique records identified, 69 studies reported across 70 publications met eligibility criteria, including 6 records identified from bibliography searches. Thalassemia prevalence estimates varied across countries and even within countries. Across 23 population-based studies reporting clinically significant alpha-thalassemia (e.g., hemoglobin H disease and hemoglobin Bart's hydrops fetalis) and/or beta-thalassemia (beta-thalassemia intermedia, major, and/or hemoglobin E/beta-thalassemia), prevalence estimates per 100 000 people ranged from 0.2 in Spain (over 2014-2017) to 27.2 in Greece (2010-2015) for combined beta- plus alpha-thalassemia; from 0.03 in Spain (2014-2017) to 4.5 in Malaysia (2007-2018) for alpha-thalassemia; and from 0.2 in Spain (2014-2017) to 35.7 to 49.6 in Iraq (2003-2018) for beta-thalassemia. Overall, the estimated prevalence of thalassemia followed the predicted pattern of being higher in the Middle East, Asia, and Mediterranean than in Europe or North America. However, population-based prevalence estimates were not found for many countries, and there was heterogeneity in case definitions, diagnostic methodology, type of thalassemia reported, and details on transfusion requirements. Limited population-based birth prevalence data were found. Twenty-seven studies reported thalassemia prevalence from non-population-based samples. Results from such studies likely do not have countrywide generalizability as they tended to be from highly specific groups. To fully understand the global prevalence of thalassemia, up-to-date, population-based epidemiological data are needed for many countries.

Risk and protective factors for resilience among adolescents and young adults with beta-thalassemia major

BACKGROUND

Resilience is the ability to overcome adversity in response to a potentially traumatic event. It can relieve people's discomfort and build personal capacity when facing a stressful situation such as beta thalassemia major. Resilience is a complex and multidimensional concept and is influenced by protective and risk factors. Therefore, the aims of the present study were to (1) investigate the relationship between protective (social support and hope) and risk (uncertainty and defensive coping) factors with resilience and (2) examine the mediating role of courageous coping between these protective and risk factors in resilience.

METHODS

This descriptive-analytical study was performed on 312 adolescents and young adults with beta-thalassemia major aged 12-24 years; they were selected using purposeful sampling from two different outpatient thalassemia clinics in the south of Iran. Data were collected in a face-to-face survey using Zimmet Multidimensional Scale of Perceived Social Support, Herth Hope, Stewart Uncertainty in Illness scale, Jalowiec Coping, and Connor-Davidson resilience Scale from April 2022 to November 2022. The collected data were analyzed using descriptive tests, Pearson correlation, and a structural equation model.

RESULTS

According to the main findings of mediation analysis, courageous coping partially mediated the relationship between social support and resilience [(β = 0.042; 95% BC CI (0.003, 0.131)] and fully mediated the relationship between hope and resilience [(β = 0.166; 95% BC CI (0.031, 0.348)]. In other cases, uncertainty and defensive coping had a direct and indirect effect on resilience, respectively.

CONCLUSION

Based on these results, health professionals and healthcare policymakers should consider this mediator in developing programs to improve resilience. Also, the use of courageous coping could modulate the effect of defensive coping on resilience. Therefore, teaching the use of courageous coping can play an important role in improving resilience.

Evaluation and relation of oral health-related quality of life and oral health status in Thalassemia Major patients, a cross-sectional study

BACKGROUND

Beta-Thalassemia is the most common human inherited disease, directly impacting patients' physical and psychosocial aspects. The present study evaluated oral health status, oral health-related quality of life (OHRQoL), and their correlation in Thalassemia Major patients.

METHODS

Two hundred Thalassemia Major patients aged 12-49 participated in this cross-sectional study. Subjects were selected among the patients referred to the Faculty of Dentistry of Isfahan University of Medical Sciences using simple sampling. Oral Health Impact Profile 14 (OHIP 14) was used to assess OHRQoL. The decayed, Missing, and Filled Teeth (DMFT) index was used as an oral health index. SPSS 22 was used for analysis, using T and Pearson Correlation tests.

RESULTS

53% of participants were female, and 47% were male. The mean OHIP-14 score (± SD) was 13.20 (± 7.01). The mean DMFT score was 9.54 (± 5.72). DMFT and total OHIP 14 scores correlated significantly (p < 0.001, r = 0.78). All domains of the OHIP-14 score were also significantly correlated with DMFT (p < 0.05).

CONCLUSIONS

Poor oral health conditions might adversely affect OHRQoL in TM patients. It seems necessary to provide oral treatment needs in order to improve OHRQoL in patients suffering from this particular disease.

The Battle against Thalassemia in Pakistan: Way to Move Forward

Thalassemia, one of the most common genetic hemoglobinopathy, is yet still an economy-depriving disorder, prevalent throughout the world. Specifically in Pakistan, numerous factors have led to the ever-increasing numbers of the affected masses. Amidst its battle with other diseases, it is worthy to highlight that the country did not overlook this disorder and hence, significant work has been done to change the thalassemia status of the country. From the establishment of reforms to private philanthropic organizations, Pakistan is actively fighting against the disorder. However, some more practical working and well-devised planning can help the country, attain a thalassemic-free status.

Major histocompatibility complex (MHC) antigens polymorphism and alloimmunization study in thalassemia patients with febrile non-hemolytic transfusion reaction (FNHTR)

OBJECTIVES

HLA alloimmunization is one of the most troublesome consequence of regular transfusion which is itself a mainstay measure to provide longevity to the thalassemia patients. Febrile non-hemolytic transfusion reaction (FNHTR) is one of the most common complication which might be related to the HLA alloimmunization. Here, we studied the HLA antigenic system and alloimmunization rate in the Iranian β-thalassemia patients who suffered from FNHTR compare to the β-thalassemia patients without FNHTR.

MATERIALS & METHODS

Total of 60 β-thalassemia patients with FNHTR (case group) and 20 β-thalassemia patients without FNHTR (control group) randomly have been selected and enrolled in the study. All were tested for HLA-A and -B loci by PCR-SSP method and also for the presence of anti-lymphocyte antibodies by LIFT method. Comparisons between two groups were performed by Pearson's χ2 test.

RESULTS

Totally, a significant predominance was noted for two HLA alleles, HLA-A*24 (P = 0.029) and B*55 (P = 0.034) which have higher prevalence in control group. Although no significant association was found between the presence of anti-leukocyte antibodies and the development of FNHTR, the HLA-A*32 (P = 0.047) allele was considered as possible genetic markers in the susceptibility to the development of anti-leukocyte antibodies.

CONCLUSION

Here some evidences about the possible role of HLA polymorphism in susceptibility to FNHTR are provided. Those results indicated that HLA-A*24 and HLA-B*55 might play protective role on inducing FNHTR in β-thalassemia patients. Further studies which investigate the allele level of HLA-I alongside with specific reactivity of HLA-I antibodies might reveal more deep data about these phenomena.

Problem of borderline hemoglobin A2 levels in an Iranian population with a high prevalence of α- and β-thalassemia carriers

Background

It is difficult to classify a small fraction of α- and β-thalassemia (α- and β-thal) carriers based on their Hb A2 levels. Here, we report the results of a molecular investigation in a cohort of thalassemia carriers with borderline Hb A2 levels originated from western Iran.

Results

The documents of 5956 α- or β-thal carriers were reviewed. The frequency of individuals with borderline Hb A2 levels in this cohort was 436 (7.32%). A total of 12 different α-thal and 27 different β-thal variants were identified in this study.

Conclusions

Our data showed that individuals with borderline Hb A2 are not uncommon in our population. Moreover, preselection of α- and β-thal carriers with borderline Hb A2 levels based on Hb A2, mean corpuscular volume (MCV), and mean cell hemoglobin (MCH) is not advisable in our population. Therefore, it is necessary to investigate both α- and β-globin genes in cases with borderline Hb A2 levels, especially if the partner is a carrier of β-thal or α0-thal.

Prevalence and determinants of anemia among Iranian population aged ≥35 years: A PERSIAN cohort-based cross-sectional study

Background

So far, no comprehensive studies have been performed to assess burden and determinants of anemia in Iran. In the present study, we aimed to answer this query using the data obtained from the Prospective Epidemiological Research Studies in IrAN (PERSIAN).

Methods

In this cross-sectional study, we included 161,686 adult participants (aged 35 years and older) from 16 provinces of Iran. Anemia was defined as a hemoglobin concentration of <13 g/dL in males and <12 g/dL in females. To evaluate the association between anemia and different factors, we used the multivariable Poisson regression analysis with robust variance by applying adjusted prevalence ratio (PR) with 95% confidence interval (CI).

Results

Of the total number of subjects, 72,387 (44.77%) were male and others were female. Mean age was 49.39±9.15 years old. The overall age- and sex-standardized prevalence of anemia was 8.83% (95% CI: 8.70–8.96%) in the included population. The highest and the lowest age- and sex-standardized prevalence of anemia pertained to Hormozgan (37.41%, 95% CI: 35.97–38.85%) and Kurdistan (4.57%, 95% CI: 3.87–5.27%) provinces, respectively. Being female (PR = 2.97), rural residence (PR = 1.24), being retired (PR = 1.53) and housewife (PR = 1.11), third and fourth wealth status quartiles (PR = 1.09 and PR = 1.11, respectively), being underweight (PR = 1.49), drug user (PR = 1.35), inadequate sleep (PR = 1.16), poor physical activity (PR = 1.15), diabetes (PR = 1.09), renal failure (PR = 2.24), and cancer (PR = 1.35) were associated with increased risk of anemia. On the other hand, illiteracy (PR = 0.79) and abdominal obesity (PR = 0.77) decreased the risk of anemia.

Conclusions

According to the results, a variable prevalence of anemia was observed across the included provinces. We tried to provide an informative report on anemia prevalence for health professionals and authorities to take measures for identification and management of the cases of anemia in high-prevalence areas.

Subclinical Left Ventricular Dysfunction in Children and Adolescence With Thalassemia Intermedia

BACKGROUND

Cardiac complications are important causes of morbidity in patients with thalassemia intermedia (TI). We aimed to assess left ventricular (LV) function, using new tissue Doppler imaging (TDI) indices, in order to diagnose early ventricular impairment in asymptomatic children and adolescence with the TI.

MATERIALS AND METHODS

We investigated possible differences in echocardiographic systolic and diastolic parameters between a population of 28 asymptomatic patients (mean age, 13.6 ± 5.7 years) and 35 age-matched healthy control members. All of them underwent 2-D, pulsed Doppler, and tissue Doppler echocardiographic studies for the assessment of the LV mass, Trans-mitral velocities, mitral annular systolic and diastolic velocities, myocardial performance index (MPI), and myocardial acceleration during isovolumic contraction (IVA). The cardiac iron load was estimated by magnetic resonance imaging T2*.

RESULTS

Left ventricular hypertrophy (LVH) was found in 13 (46.4%) patients. We found significantly reduced TDI-derived peak systolic myocardial velocity (s') in patients, whereas no significant difference was identified between the patients and control group members when the IVA was compared. The ratio of peak mitral inflow velocity to annular early diastolic velocity (E/e') of the mitral valve as an index of the diastolic function was significantly higher in patients (9 ± 1 vs. 6 ± 1, p < 0.05). Choosing a TDI-derived MPI > 0.33 as a cutoff point, the global LV dysfunction was detected with a sensitivity of 78% and a specificity of 80%. The patients with LVH significantly exhibited higher values of TDI-MPI and lower values of s' velocity and IVA when compared against the subjects with normal LV mass.

CONCLUSION

Subtle LV systolic and diastolic dysfunction develops early in young patients with the TI who have normal cardiac iron concentration. Moreover, LV remodeling as a main cardiac adaptive response plays a principal role in developing myocardial impairment.

Resistance-associated substitutions (RASs) to HCV direct-acting antivirals (DAAs) at baseline of treatment in thalassemia patients: a referral center study

Patients with thalassemia major are at high risk of hepatitis C through blood transfusion from donors infected by hepatitis C virus (HCV). The use of direct-acting antiviral (DAA) therapy against such HCV infections has increased in different populations. However, resistant viral variants can affect treatment outcomes, and therefore improved surveillance strategies are needed. Accordingly, we aimed to evaluate resistance-associated substitutions (RASs) to HCV DAAs at the baseline of treatment in thalassemia patients in a referral center. Out of 89 thalassemia patients who suffered from HCV infection and were referred to our center between 2016 and 2017, 43 underwent further analysis of the HCV nonstructural proteins NS5A and NS5B using polymerase chain reaction (PCR) sequencing methods. Unique primers were designed using bioinformatics software for separate detection of HCV subtypes 1a, 3a, and 1b. Detection of RASs was performed based on previously published literature. Statistical analysis was carried out using SPSS version 19. The participants, 60.4% (26/43) of whom were male, had a mean age ± standard deviation (SD) of 33.0 ± 5.0 years. HCV subtype 1a was found in 27 cases, 3a in 13, and 1b in three. In HCV subtype 1a there were 163 mutations in NS5A and 212 mutations in NS5B. The frequency of RASs was 20.9% (8 RASs in 9 patients), including M28V and H58P in subtype 1a, L28M, R30Q, C316N, and C316S in subtype 1b, and S24F in subtype 3a. Statistically, the subtype 1b and a higher mutation rate in NS5A were associated with RASs (p-value < 0.05). The emergence of natural RASs to HCV DAAs serves as a warning of the risk of drug resistance in response to the broad usage of antivirals. However, relapses in these DAA-treated HCV-infected thalassemia patients are rarely reported. Our findings indicate that the prevalence of RASs prevalence at baseline was 20.9% in these patients, and this calls for extrapolation to a larger population study, as highlighted in other studies, with larger sample sizes, high-throughput methods, and follow-up in order to fully evaluate treatment outcomes in RASs-detected individuals. Optimized therapeutic strategies, particularly in complex, difficult-to-cure patients, can effectively prevent DAA treatment failure as a result of selection for RASs.

COVID-19 and Thalassaemia in Iran

Coronavirus disease 2019 (COVID-19) has had and continues to have a significant medical, public health, social and economic impact on every society around the world. Some groups of chronic patients including thalassaemia and other haemoglobin disorders were considered from the beginning of the pandemic, as vulnerable and high risk ones with regards to a more severe clinical outcome of the infection with severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2). This is because patients with thalassaemia can present with many and multiple co-morbidities including diabetes, heart, liver, endocrine and other conditions mainly secondary to iron overload and consequent to ineffective or suboptimal medical care and/or adherence to chelation treatment in particular. Transfusion dependent patients with β-thalassaemia have been greatly affected across the world, including in Iran, a country geographically situated in the so called thalassaemia belt. Iran with about 20,000 patients with β-thalassaemia and quite successful disease specific prevention and management national programmes faced challenges similar to others. Blood shortages for example consequent to COVID-19 precaution measures taken in every country to contain the virus and the difficulties in accessing drugs including lifesaving ones (iron chelation medication) constitute major challenges. In Iran however, and despite the multiple difficulties as described above, SARS-CoV-2 had a rather small impact regarding infection rates as compared to the rest of the countries, albeit a higher mortality rate reaching 26.5% amongst COVID-19 diagnosed patients. More comprehensive data however from a bigger number of patients with thalassaemia across the world infected with SARS-CoV- 2 is necessary to draw any reliable conclusions as to the level of vulnerability to SARS-CoV-2 and importantly the clinical impact of this virus in these patients.