Bone-related complications of transfusion-dependent beta thalassemia among children and adolescents

An In-Depth Analysis of Variable Dynamics Influencing Bone Mineral Density in Transfusion-Dependent Thalassemia Patients

The survival of patients with transfusion-dependent thalassemia has increased with optimal blood transfusion. In adult patients with thalassemia, iron toxicity due to repeated blood transfusion is the main contributing factor causing decreased bone density and leads to mechanical disruption in the bone structure. This study aimed to analyze the variables affecting bone mineral density (BMD) in patients with thalassemia major. We enrolled patients with transfusion-dependent thalassemia who visited the Hasan Sadikin Hospital Bandung outpatient clinic. Participants underwent anthropometric measurement, laboratory, and BMD examination. Bivariate analysis was performed to determine the correlation between clinical data and BMD by Pearson or Rank-Spearman depending on data distribution. Multivariate analysis was performed to determine the most influential variables using linear regression analysis. p < 0.05 was considered statistically significant. Overall, 59 participants were included. BMD was significantly correlated with body mass index (BMI), sex, average pre-transfusion hemoglobin level, blood transfusion volume, and vitamin D, with coefficient r values of 0.47, 0.34, - 0.27, and - 0.28 (p < 0.05), respectively. BMI was the variable that most influenced BMD, with 0.39 coefficient value, an adjusted coefficient value of 0.32 (0.01-0.04), and p = 0.04. Receiver operating characteristic analysis showed BMI had the highest area under the curve (AUC) in all examination areas, especially in the hip area, with 0.800 AUC. 77.8% sensitivity, and 71.7% specificity. BMD was correlated with BMI, sex, average pre-transfusion hemoglobin level, blood transfusion volume, and vitamin D, with BMI being the most influential factor affecting BMD.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12288-024-01864-1.

Prevalence and Associated Factors of Zinc and Vitamin D Deficiencies in Pediatric and Young Adult Patients with Non-Transfusion-Dependent Thalassemia

Micronutrient deficiencies pose significant long-term risks in non-transfusion dependent thalassemia (NTDT) patients. Zinc deficiency can impair growth, cause atopic dermatitis, and increase susceptibility to respiratory infections, while vitamin D deficiency disrupts bone mineralization and metabolism. This study aimed to determine the prevalence of zinc and vitamin D deficiencies and investigate associated factors in pediatric to young adult NTDT patients. A cross-sectional study was conducted at Chiang Mai University Hospital, enrolling NTDT patients aged 5 to 25 years who received fewer than three transfusions annually. Serum zinc and vitamin D levels were measured. Patients and parents completed a 3-day food diary and a sun exposure questionnaire. Zinc deficiency was defined as levels below the reference level for age. Vitamin D deficiency was defined as levels <20 ng/mL. Clinical and hematologic parameters were compared between groups with and without deficiencies. Forty-five patients with NTDT were enrolled, including 23 males (51.1%) males, with a mean age of 12.8 ± 5.3 years. Zinc deficiency affected 13 patients (28.9%), while 23 patients (51.1%) had vitamin D deficiency. Thinness was observed more frequently in patients with zinc deficiency. However, this finding did not reach statistical significance. Older age and inadequate sun exposure were associated with vitamin D deficiency. This study underscores a high prevalence of zinc and vitamin D deficiencies in pediatric and young adult NTDT patients and identifies the associated factors. Addressing and monitoring these deficiencies are crucial for optimizing long-term health outcomes in this patient group.

BIA-derived muscle indicator thresholds for malnutrition risk prediction in children with β-thalassemia: a cross-sectional study

BACKGROUND

Malnutrition is a significant concern in children with β-thalassemia, impacting their growth and overall health. This study aimed to establish optimal thresholds for predicting malnutrition risk in children with β-thalassemia using muscle mass indicators derived from Bioelectrical Impedance Analysis (BIA).

METHODS

A cross-sectional study was conducted with 162 pediatric patients diagnosed with β-thalassemia. Nutritional status of them was assessed using the World Health Organization (WHO) Child Growth Standards and references. BIA was performed to obtain fat-free mass (FFM), skeletal muscle mass (SMM), and soft lean mass (SLM). Propensity score matching (PSM) was used to control for age and gender. Receiver Operating Characteristic (ROC) curves were constructed to evaluate the diagnostic performance.

RESULTS

SLM-change < 6% demonstrated the highest sensitivity [0.82, 95% confidence interval (CI) 0.72-0.92] and a negative predictive value of 0.83 (95% CI 0.74-0.93), while FFM-change < 4% showed more balanced performance with a sensitivity of 0.58 (95% CI 0.45-0.71) and a specificity of 0.65 (95% CI 0.56-0.74). Percentage change indicators (FFM-change, SLM-change, and SMM-change) exhibited remarkable stability before and after PSM, indicating minimal influence from age and gender.

CONCLUSIONS

This study established novel, age-adaptive thresholds (SLM-change < 6% and FFM-change < 4%) for predicting malnutrition risk in children with β-thalassemia. The findings suggest that these thresholds could serve as effective references to assess nutritional status across different age groups, providing new perspectives for personalized nutritional management strategies.

A Systematic Review and Meta-Analysis of Stature Growth Complications in β-thalassemia Major Patients

Background

Blood transfusion is a traditional treatment for β-thalassemia (β-thal) that improves the patients' anemia and lifespan, but it may lead to iron overload in parenchymal tissue organs and endocrine glands that cause their dysfunctions as the iron regulatory system can't excrete excess iron from the bloodstream.

Objective

To evaluate the prevalence of iron-related complications (short stature, growth retardation, and growth hormone deficiency) in β-thalassemia major (βTM) patients.

Methods

We performed an electronic search in PubMed, Scopus, and Web of Sciences to evaluate the prevalence of growth hormone impairment in β-thalassemia major (βTM) patients worldwide. Qualities of eligible studies were assessed by the Joanna Briggs Institute checklist for the prevalence study. We used Comprehensive Meta-Analysis (Version 2) to calculate the event rate with 95% CIs, using a random-effects model for all analyses.

Findings

Seventy-four studies were included from five continents between 1978 and 2019; 70.27% (Asia), 16.21% (Europe), 6.75% (Africa), 2.70% (America), 1.35% (Oceania), and 2.70% (Multicenter). The overall mean age of the participants was about 14 years. The pooled prevalence of short stature (ST) was 48.9% (95% CI 35.3-62.6) and in male was higher than female (61.9%, 95% CI 53.4-69.7 vs. 50.9%, CI 41.8-59.9). The pooled prevalence of growth retardation (GR) was 41.1% and in male was higher than in female (51.6%, 95% CI 17.8-84 vs. 33.1%, CI 9.4-70.2). The pooled prevalence of growth hormone deficiency (GHD) was 26.6% (95% CI 16-40.8).

Conclusion

Our study revealed that near half of thalassemia patients suffer from growth impairments. However, regular evaluation of serum ferritin levels, close monitoring in a proper institute, suitable and acceptable treatment methods besides regular chelation therapy could significantly reduce the patients' complications.

Vitamin D and bone health status in beta thalassemia patients-systematic review

Thalassemia is a chronic congenital disease characterized by a combination of endocrine and metabolic disorders. Bone disease is a very common complication related to the poor absorption of calcium, the secondary chronic renal disease with low vitamin D, as well as multiple endocrine risk factors. The aim of this systematic review was to estimate the prevalence of vitamin D deficiency in thalassemia, as well as its association with osteoporosis/low bone mass. A systematic review was carried out using PubMed/Medline, Cochrane, and EBSCO databases. The methodological quality of the included studies was assessed with the validated Newcastle-Ottawa Quality Assessment Scale adapted for cross-sectional studies and cohort studies respectfully and the Cochrane Collaboration for clinical trials. After application of predetermined exclusion criteria compatible with the PICOS process, a total of 12 suitable articles were identified. The prevalence of vitamin D deficiency varied considerably. Only five of the reviewed studies examined the correlation between vitamin D levels and BMD of which just three showed a statistically significant positive association of mild/moderate grade. Vitamin D deficiency is a common comorbidity in patients with thalassemia. However, both its prevalence and its severity vary considerably in different populations, and existing evidence is insufficient to conclude whether vitamin D supplementation is also associated with BMD improvement in this special population group.

Association of VDBP rs4701 Variant, but not VDR/RXR-α Over-Expression with Bone Mineral Density in Pediatric Well-Chelated β-Thalassemia Patients

BACKGROUND

The reduced rate of bone formation despite the availability of vitamin D has been reported in β-thalassemia. Genetic factors, together with environmental ones, could be implicated in this condition. Since vitamin D binding protein (VDBP) maintains bioavailability of vitamin D which binds to vitamin D receptor (VDR)-retinoid X receptor alpha (RXRA) heterodimer to exert its molecular actions, we speculated that vitamin D metabolic-axis expression signature and variants could be potential molecular candidates for bone turnover/disease in thalassemia. To this end, this study aims to analyze VDR/RXRA expression signature, and two VDBP variants in a pilot sample of Egyptian β-thalassemia children in correlation with bone mineral density (BMD).

PATIENTS AND METHODS

Forty-four well-chelated β-thalassemia children and 40 unrelated controls were enrolled. The serum bone chemistry profile was measured. Peripheral blood mononuclear cells (PBMN) VDR/RXRA expression levels were quantified by Real-Time quantitative reverse transcription-polymerase chain reaction (qRT-PCR). VDBP rs7041 and rs4588 variants were identified by Real-Time allelic discrimination assay. All patients were subjected to lumbar-spine Dual-energy X-ray absorptiometry (DEXA).

RESULTS

VDR/RXRA expressions were significantly higher in β-thalassemia children compared to controls (P = 0.001 and <0.001, respectively) and showed higher values in β-thalassemia major relative to β-thalassemia intermedia. Expression levels of both genes were not associated with sex or BMD. However, VDBP rs4701 genotyping revealed lower BMD-L4 and a higher frequency of osteoporosis.

CONCLUSIONS

β-Thalassemia children had higher expression levels of PBMN VDR/RXRA. VDBP rs4701 variant was associated with osteoporosis in our β-thalassemia patients on vitamin D supplementation. Further large-scale studies in other ethnic populations are warranted.

Prevalence of endocrine disorders and their associated factors in transfusion-dependent thalassemia patients: a historical cohort study in Southern Iran

PURPOSE

Transfusion-dependent beta-thalassemia (TDT) patients suffer from various endocrinopathies. The main contributing factor associated with these complications is iron overload, secondary to frequent blood transfusions. To improve patients' quality of life, we evaluated the prevalence of endocrine disorders while considering the associated factors for further assessment.

METHODS

Seven hundred thirteen transfusion-dependent thalassemia patients with age range 10-62 years were enrolled in this study. Serum calcium, phosphorous, fast blood sugar, ferritin, 25-OH vitamin D, free thyroxin, thyroid-stimulating hormone and parathyroid hormone were assessed. Bone mineral density was measured by dual-energy X-ray absorptiometry.

RESULTS

In total, 86.8% of the TDT patients suffered from at least one endocrinopathy. The prevalence of endocrinopathies in descending order of frequency was low bone mass (72.6%), hypogonadism (44.5%), diabetes mellitus (15.9%), hypoparathyroidism (13.2%), and hypothyroidism (10.7%). Age, body mass index and splenectomy were significantly associated with most of the endocrine disorders.

CONCLUSION

Endocrine complications are frequently observed in TDT patients. Splenectomy is a major risk factor and should be generally avoided unless it is highly indicated. Periodic surveillance of endocrine function and proper management of iron overload are advised.

Hepatic Hemosiderosis Contributes to Abnormal Vitamin D-PTH Axis in Thalassemia Major

OBJECTIVE

The aim of this study was to evaluate the vitamin D-PTH axis in thalassemia major (TM) in relation to hepatic siderosis liver iron content.

DESIGN AND PARTICIPANTS

In this case-controlled observational study, vitamin D-PTH axis was studied in 158 TM and 84 age and ethnicity-matched healthy nonthalassemic controls attending University College Hospital, London. Patients were classified as 25-hydroxy vitamin D (25-OHD) insufficient and sufficient if the value was less than or greater than 50 nmol/L, respectively. 25-OHD data were evaluated in relation to markers of iron load in TM.

RESULTS

In TM, 25-OHD insufficiency was 8-fold higher than the control group (odds ratio [OR], 8.1; 95% confidence interval [CI], 4.3-15.0; P<0.001). Similarly, serum PTH (P<0.001), calcium (P<0.001), and phosphate levels (P<0.05) were also significantly lower in TM compared with the controls. In TM, serum ferritin of >2500 μg/L (OR, 5.3; 95% CI, 2.3-12.3; P<0.01), liver iron of >7 mg/g dry weight (OR, 8.8; 95% CI, 3.5-10.3; P<0.001), and serum alanine aminotransferase of >50 IU/L (OR, 9.7; 95% CI, 4.0-23.5; P<0.001) were independent risk factors for low 25-OHD levels.

CONCLUSIONS

Our results suggest that TM had a 8-fold higher risk of 25-OHD insufficiency compared with the controls. This was likely to be associated with hepatic hemosiderosis.

Age-related changes in biochemical bone profile in thalassemic children

BACKGROUND

Osteopathy is an important cause of morbidity in β-thalassemia major (TM). Although many of the etiopathological factors implicated in thalassemic osteoporosis commence in early disease phases during childhood, limited information exists on bone turnover in children with TM. This study was conducted with the objective to compare bone turnover markers (BTMs) in thalassemic children at different ages.

METHODS

In a cross sectional case control study, 47 children (age range, 1.5-18 years) with TM were recruited. BTMs were compared to eighteen age- and sex-matched healthy controls and to 16 adults (age range, 19.67-31.08 years) with TM.

RESULTS

Thalassemic children displayed unbalanced bone turnover with an increased bone resorption (shown by high levels of tartrate-resistant acid phosphatase 5b (TRACP5), receptor activator of nuclear factor-kappa B ligand (sRANKL) and sRANKL/osteoprotegerin (OPG) ratio) and a decreased bone neoformation (shown by low levels of osteocalcin (OC)) when compared to healthy children. TRACP5b was the only BTMs studied that showed a significant correlation with age in thalassemic children. For the whole thalassemic children group, regression analyses showed an influence of sex hormones replacement therapy on TRACP5b; pretransfusion hemoglobin and splenectomy on sRANKL; pretransfusion hemoglobin on sRANKL/OPG; and pretransfusion hemoglobin and serum ferritin on OC.

CONCLUSION

The present study confirms that TM has profound effects on bone metabolism starting from early childhood. The early onset of bone turnover disturbances in TM indicates the need to investigate possible option to intervene early.

Rheumatological complications of beta-thalassaemia: an overview

Beta-thalassaemia, an autosomal recessive haemoglobinopathy, ranks among the most frequent monogenetic diseases globally. The severe form of the disease, beta-thalassaemia major, is accompanied by progressive involvement of multiple organ systems as a result of the disease pathophysiology as well as iron overload from blood transfusions on a regular basis. Some of the manifestations might also be caused by medications used to manage iron overload. The purpose of this review is to highlight the rheumatological complications of beta-thalassaemia, which include musculoskeletal manifestations, such as arthritis and arthropathies, joint effusions, osteoporosis, bone fractures and myalgias, in addition to CTDs, such as pseudoxanthoma elasticum. Rheumatologists are strongly encouraged to take part in a multidisciplinary approach to the management of this debilitating disease.

Biochemical Markers of Bone Turnover in Patients with β-Thalassemia Major: A Single Center Study from Southern Pakistan

Objectives. Skeletal complications in β-homozygous thalassemic patients are uncommon but often debilitating, even amongst children and adolescent patients with well maintained transfusion and chelation therapy. The aim is to evaluate the biochemical markers of bone turnover in regularly transfused thalassemic patients and its possible correlations with demographic data and hematological and biochemical markers. Methods. In this prospective cross-sectional study, 36 β-thalassemia major patients were enrolled from March 2012 to March 2014. All patients underwent complete blood counts, LFTs, serum ferritin, serum calcium, phosphorus, serum albumin, alkaline phosphatase, 25-OH vitamin D, and parathormone (PTH) levels. Results. There were 17 males and 19 females with mean age of 12.56 ± 5.9 years. Hypocalcemia and hypophosphatemia were seen in 66.6% and 19.4%, respectively, while 25-OH vitamin D deficiency was present in 72.2% of thalassemic children and adolescents. Hypoparathyroidism was seen in 13.8% while hyperparathyroidism was detected in 8.3% of patients. There was direct correlation between serum phosphorus and ferritin levels (P < 0.05). No correlation was found between indirect bilirubin and skeletal parameters, calcium and parathyroid hormone (P > 0.05). Conclusions. Biochemical profile is significantly altered in patients with β-thalassemia major and bone associated biochemical abnormalities like hypocalcaemia, 25-OH vitamin D deficiency, and hypophosphatemia are not uncommon in Pakistani patients with thalassemia major.

Bone health in children and adolescents with chronic diseases that may affect the skeleton: the 2013 ISCD Pediatric Official Positions

The aim of this Task Force was to review the use of dual-energy X-ray absorptiometry (DXA) in children and adolescents with underlying chronic diseases that pose risk factors for compromised bone health, such as inflammation, glucocorticoid therapy, or decreased mobility. The Task Force systematically analyzed more than 270 studies, with an emphasis on those published in the interval since the original 2007 Position Statements. Important developments over this period included prospective cohort studies demonstrating that DXA measures of areal bone mineral density (aBMD) predicted incident fractures and the development of robust reference data and strategies to adjust for bone size in children with growth impairment. In this report, we summarize the current literature on the relationship between DXA-based aBMD and both fracture (vertebral and non-vertebral) outcomes and non-fracture risk factors (e.g., disease characteristics, ambulatory status, and glucocorticoid exposure) in children with chronic illnesses. Most publications described the aBMD profile of children with underlying diseases, as well as the cross-sectional or longitudinal relationship between aBMD and clinically relevant non-fracture outcomes. Studies that addressed the relationship between aBMD and prevalent or incident fractures in children with chronic illnesses are now emerging. In view of these updated data, this report provides guidelines for the use of DXA-based aBMD in this setting. The initial recommendation that DXA is part of a comprehensive skeletal healthy assessment in patients with increased risk of fracture is unchanged. Although the prior guidelines recommended DXA assessment in children with chronic diseases at the time of clinical presentation with ongoing monitoring, this revised Position Statement focuses on the performance of DXA when the patient may benefit from interventions to decrease their elevated risk of a clinically significant fracture and when the DXA results will influence that management.