The effectiveness and safety of thyroxine replacement therapy for children with down syndrome and subclinical or congenital hypothyroidism—A systematic review

Abstract

Introduction: Down syndrome (DS) is the most common chromosomal abnormality causing mental handicap in humans. Children with DS have significant medical problems and developmental delay which are further impaired by hypothyroidism. Those clinical features are potentially improved by using thyroxine replacement therapy. Objectives: To examine the evidence of effectiveness (motor & mental development) and safety of thyroxine supplementation in the treatment of SH and CH in children with DS. Methods: Several medical data bases (MEDLINE, EMBASE, CINAHL, Cochrane, Clinical Trials Gov, Essential Evidence and Google) were searched until 20 October, 2011, for randomized control trials (RCTs) that had examined thyroxine’s effectiveness and safety in the treatment of SH or CH in children with DS. Results: There were two high quality RCTs that examined thyroxine in the treatment of CH in children with DS, and no RCTs were found to have examined the effectiveness of thyroxine for SH in children with DS. Conclusion: The RCT which met our inclusion criteria provides the reliable evidence in recommending thyroxine for the treatment of CH in children with DS which is similar to the guidelines for general population. The absence of RCTs examining the treatment of SH in Children with DS indicates the need to conduct such trials.