Vol. 6, Issue 1, Part A (2024)

Background: Goitre is a common thyroid disorder with varying aetiologies, including iodine deficiency and thyroid hormone imbalances. Management options typically involve iodine supplementation or levothyroxine therapy. Despite their widespread use, the comparative efficacy of these interventions remains unclear. To systematically review and compare the efficacy of iodine supplementation and levothyroxine in managing goitre with a focus on clinical outcomes, thyroid function, and adverse effects. 
Methods: Systematic review of randomized controlled trials (RCTs) and observational studies. 
Data Sources: PubMed, Cochrane Library, Scopus, and EMBASE, searched from 2014 to October 2024. 
Eligibility Criteria: Studies comparing iodine supplementation and levothyroxine in adults or children with goiter, reporting outcomes such as goiter volume reduction, thyroid function improvement, and adverse effects. 
Data Synthesis: Effect sizes were summarized using meta-analysis where feasible, and findings were presented narratively when heterogeneity was high.
Results: 6 studies were included. Levothyroxine showed superior efficacy in reducing goiter volume in individuals with thyroid hormone deficiency, while iodine supplementation was more effective in iodine-deficient populations. Iodine improved thyroid function in iodine-deficient individuals but had limited impact in euthyroid patients. Levothyroxine normalized thyroid hormone levels but was associated with higher rates of subclinical hyperthyroidism. Iodine supplementation rarely caused adverse events, while levothyroxine use was associated with mild cardiac effects in some cases. 
Conclusion: Both iodine supplementation and levothyroxine are effective in managing goiter, but their efficacy depends on the underlying etiology. Iodine supplementation is preferred for iodine-deficiency-related goiter, while levothyroxine is more effective for goiter caused by hypothyroidism. Clinicians should tailor treatment based on individual patient profiles and underlying causes.