Diabetes in Patients with ß-thalassemia or other Hemoglobinopathies - Analysis from the DPV Database

Endocrinopathies in beta thalassemia: a narrative review

Beta thalassemia is the most common genetic blood disorder, characterized by reduced production or complete absence of beta-globin chains. The combination of systematic red blood cell transfusion and iron chelation therapy is the most readily available supportive treatment and one that has considerably prolonged the survival of thalassemia patients. Despite this, the development of endocrine abnormalities correlated with beta thalassemia still exists and is mostly associated with iron overload, chronic anemia, and hypoxia. A multifactorial approach has been employed to investigate other factors involved in the pathogenesis of endocrinopathies, including genotype, liver disease, HCV, splenectomy, socioeconomic factors, chelation therapy, and deficiency of elements. The development of specific biomarkers for predicting endocrinopathy risk has been the subject of extensive discussion. The objective of the present narrative review is to present recent data on endocrinopathies in beta thalassemia patients, including the prevalence, the proposed pathogenetic mechanisms, the risk factors, the diagnostic methods applied, and finally the recommended treatment options.

Endocrinopathies in Hemoglobinopathies: What Is the Role of Iron?

Hemoglobinopathies, including β-thalassemia and sickle cell disease (SCD), are common genetic blood disorders. Endocrine disorders are frequent manifestations of organ damage observed mainly in patients with β-thalassemia and rarely in SCD. Iron overload, oxidative stress-induced cellular damage, chronic anemia, and HCV infection contribute to the development of endocrinopathies in β-thalassemia. The above factors, combined with vaso-occlusive events and microcirculation defects, are crucial for endocrine dysfunction in SCD patients. These endocrinopathies include diabetes mellitus, hypothyroidism, parathyroid dysfunction, gonadal and growth failure, osteoporosis, and adrenal insufficiency, affecting the quality of life of these patients. Thus, we aim to provide current knowledge and data about the epidemiology, pathogenesis, diagnosis, and management of endocrine disorders in β-thalassemia and SCD. We conducted a comprehensive review of the literature and examined the available data, mostly using the PubMed and Medline search engines for original articles. In the era of precision medicine, more studies investigating the potential role of genetic modifiers in the development of endocrinopathies in hemoglobinopathies are essential.

Ocular findings in patients with transfusion-dependent β-thalassemia in southern Iran

Background

Ocular involvement may occur via several mechanisms in patients with transfusion-dependent β-thalassemia (TDT) mainly chronic anemia, iron overload and iron chelator toxicity. We aimed to evaluate the frequency of abnormal ocular findings and their relationship with hematologic parameters in TDT patients.

Methods

In this cross-sectional study from January 2018 to January 2019, a total of 79 patients with TDT over the age of 18 who were on iron-chelation therapy (ICT) were consecutively investigated. All patients were registered at the Thalassemia Comprehensive Center affiliated with Shiraz University of Medical Sciences, Shiraz, Southern Iran. Complete ophthalmic examination was performed by an expert ophthalmologist. Clinical and hematologic parameters were collected from the patients´ medical records.

Results

The mean age ± standard deviation (SD) of the patients was 28.4 ± 5.6 years (range: 18–43). Twenty-four patients (30.4%) were male and 29 (36.7%) were splenectomized. The mean ± SD of the best-corrected visual acuity (VA) was 0.960 ± 0.086 decimal, (range: 0.6–1), 0.016 ± 0.046 logMar, (range: 0–0.2). The frequency of patients with VA > 0.1 logMar was 3 (3.8%). The mean intraocular pressure (IOP) was 14.88 ± 3.34 (6–25) mmHg. Fundus abnormalities were observed in 8 patients (10.1%), consisting of increased cup-disk ratio (3.8%), vessel tortuosity (2.5%), retinal pigment epithelium degeneration (2.5%), myelinated nerve fiber layer (1.3%), and internal limiting membrane wrinkling (1.3%). No significant association was observed between fundus abnormalities, VA, or IOP with hematologic parameters (P > 0.05). TDT patients with diabetes mellitus had significantly higher IOP (P = 0.010) but similar frequency of fundus abnormalities with non-diabetic patients (P > 0.05).

Conclusions

The frequency of ocular abnormalities in our patients was lower than the previous reports. The frequency of fundus abnormalities were similar in diabetic and non-diabetic thalassemia patients indicating close monitoring and proper management of the disease and comorbidities in these patients.

Similar burden of type 2 diabetes among adult patients with sickle cell disease relative to African Americans in the U.S. population: a six-year population-based cohort analysis

Conflicting evidence exists on the epidemiology of type 2 diabetes mellitus (T2DM) among patients with sickle cell disease (SCD). This study measured the prevalence, incidence and clinical outcomes associated with T2DM in a large US population of commercially-insured adults aged ≥20 years with SCD between 2009 and 2014. Among 7070 patients with SCD, the mean age (median) was 39 (37) years and 60·8% were female. The standardized prevalence of T2DM among patients with SCD showed a modest increase, from 15·7% to 16·5% (P trend = 0·026), and was comparable to African-American respondents to the National Health and Nutrition Examination Survey (18·2%). Over 17 024 person-years, the crude incidence rate for T2DM was 25·4 per 1000 person-years. Incident T2DM was associated with comorbid hypertension (hazard ratio [HR] = 1·45, 95% confidence interval [CI] 1·14-1·83), and dyslipidaemia (HR = 1·43, 95%CI 1·04-1·96). Compared to SCD patients without T2DM, more SCD patients with T2DM had diagnoses of nephropathy (28·0% vs. 9·5%; P < 0·001), neuropathy (17·7% vs. 5·2%; P < 0·001) and stroke (24·1% vs. 9·2%; P < 0·001). Prevalence of T2DM in SCD patients is similar to the general African American population with an increasing trend in recent years. These trends support routine screening for T2DM in aging patients with SCD, especially those with comorbid hypertension and/or dyslipidaemia.