Interventions to improve symptomatology in patients with hypothyroidism and persistent symptoms: A systematic review.

Abstract Background Levothyroxine (LT4) monotherapy is the standard treatment for hypothyroidism; however, 10–15% of patients have persistent hypothyroid symptoms despite normalizing thyroid hormone levels with LT4. This study aims to summarize the best available evidence on interventions to improve symptomatology in patients with hypothyroidism and persistent symptoms. Methods A systematic search was conducted in March 2022 for randomized controlled trials (RCTs) and observational studies on interventions for adult patients with persistent hypothyroid symptoms despite biochemical euthyroidism on thyroid hormone replacement. Results Of 277 articles, seven fulfilled the inclusion criteria. 455 participants were included. Most intervention participants were female (78.6%) with a mean age of 47.5 years. Five clinical trials evaluating ginger (vs. starch), L-carnitine (vs. placebo), combination LT4 and liothyronine (LT3) (vs. LT4 or placebo), and surgery for patients with serum antithyroid peroxidase (TPO Ab) titers greater than 1000 IU/ml (vs. LT4) found inconsistent improvement in hypothyroidism related symptoms and general health. Of these clinical trials, the use of ginger and surgery showed the largest improvements in fatigue scores. One observational study comparing thyroidectomy vs observation found no impact difference on general health. Lastly, another observational study evaluating combination LT4/LT3 (vs. LT4 monotherapy) found improvement in fatigue and QoL. There were 31 (12%) adverse events in the intervention group and 18 (10.8%) in the comparator group. Conclusions There is no high-quality evidence supporting any intervention for persistent symptoms in hypothyroidism. Available evidence, limited by the risk of bias, inconsistency, and heterogeneity, suggests that some persistent symptoms, particularly fatigue, could improve with ginger and thyroidectomy. Trial registry number:PROSPERO (CRD42022318720)