Amlodipine as adjuvant therapy to current chelating agents for reducing iron overload in thalassaemia major: a systematic review, meta‐analysis and simulation of future studies

Abstract

Background and Objectives Iron overload in thalassaemia is a crucial prognostic factor and a major cause of death due to heart failure or arrhythmia. Therefore, previous research has recommended amlodipine as an auxiliary treatment to current chelating agents for reducing iron overload in thalassaemia patients. Materials and Methods A systematic review and meta‐analysis of the results of three randomized clinical trials evaluating the use of amlodipine in thalassaemia patients through 12 databases were carried out. Results Our final cohort included 130 patients. Insignificant difference in decreasing liver iron concentrations was found between amlodipine and control groups {weighted mean difference = −0·2, [95% confidence interval = (−0·55–0·15), P = 0·26]}. As regards serum ferritin, our analysis also showed no significant difference in serum ferritin between amlodipine and control groups {weighted mean difference [95% confidence interval = −0·16 (−0·51–0·19), P = 0·36]}. Similarly, there was insignificant difference in cardiac T2* between amlodipine and control groups {weighted mean difference [95% confidence interval = 0·34 (−0·01–0·69), P = 0·06]}. Conclusions Despite the growing evidence supporting the role of amlodipine in reducing iron overload in thalassaemia patients, our meta‐analysis did not find that evidence collectively significant. The results of our simulation suggest that when more data are available, a meta‐analysis with more randomized clinical trials could provide more conclusive insights.

Comparison of the effects of calcium channel blockers plus iron chelation therapy versus chelation therapy only on iron overload in children and young adults with transfusion‐dependent thalassemia: A randomized double‐blind placebo‐controlled trial

“…6,13 Two systematic reviews have suggested that there is need for more randomized controlled trials to provide more evidence in supporting the role of amlodipine in reducing iron overload in patients with thalassemia major. 14,15 In the present study, the cardiac amlodipine group. However, there was no significant change observed in patients in control group.…”

“…In recent years, some studies have shown the benefit of addition of oral amlodipine, an LTCC blocker, to standard chelation therapy in improving the cardiac T2* in TDT patients 6,13 . Two systematic reviews have suggested that there is need for more randomized controlled trials to provide more evidence in supporting the role of amlodipine in reducing iron overload in patients with thalassemia major 14,15 …”

Efficacy and safety of calcium channel blockers in preventing cardiac siderosis in thalassemia patients: An updated meta‐analysis with trial sequential analysis

“…side effects were a common untoward adverse reaction 10 . On the other hand, previous meta‐analyses pointed out that using amlodipine is not encouraged in treating iron overload as there was an insignificant difference in cardiac T2* between amlodipine and control groups 11–13 . Nevertheless, these previous meta‐analyses had some problems.…”

“…10 On the other hand, previous meta-analyses pointed out that using amlodipine is not encouraged in treating iron overload as there was an insignificant difference in cardiac T2* between amlodipine and control groups. [11][12][13] Nevertheless, these previous meta-analyses had some problems. First, the small number of studies included did not provide adequate evidence.…”