- Levothyroxine yields no left ventricular ejection fraction (LVEF) benefit at 1 year in patients who have had an acute myocardial infarction (AMI) and have subclinical hypothyroidism.
Why this matters
- The authors say that these preliminary results from a randomized controlled trial (RCT) suggest that screening for and treating subclinical hypothyroidism in these patients “is not justified.”
- The treatment and placebo groups were similar for, e.g., mean age (64.1 and 62.9 years), antiplatelet and other therapies, infarct size, and rates of ST-elevation myocardial infarction.
- LVEF was better (means±standard deviations) in both groups from baseline to 1 year after AMI.
- With levothyroxine: from 51.3% (9.1%) to 53.8% (9.7%).
- With placebo: from 54.0% (7.9%) to 56.1% (7.9%).
- No significant difference.
- Baseline LVEF was not associated with LVEF outcome.
- Patient-reported outcomes (e.g., depression scale scores, heart failure questionnaire) did not differ between groups at 1 year.
- Adverse event rates: 33.3% in the treatment group and 36.7% with placebo.
- 1 death in each group.
- Double-blind RCT, 6 UK hospitals.
- 46 patients in the levothyroxine and 49 in the placebo group.
- Primary outcome: LVEF at 52 weeks.
- Funding: UK National Institute for Health Research.
- Initiation dose was small.
- LVEF was preserved at baseline in most patients.