Level 1: Likely reliable evidence
Graves’ disease is the most common cause of hyperthyroidism and frequently causes changes to the eye and surrounding structures, including retraction of the eyelid, bulging of the eye, and restricted eye movements. Even mild symptoms can affect quality of life.
A recent randomized trial evaluated the efficacy of two drugs, selenium and pentoxifylline, to either improve or limit the progression of symptoms in patients with mild Graves’ orbitopathy (N Engl J Med. 2011;364:1920-1931). A total of 159 patients were randomized to selenium 100 mg orally twice daily vs. pentoxifylline 600 mg orally twice daily vs. placebo for six months.
Quality of life was measured on a 100-point scale that included measures of visual function and appearance. A change of at least six points was considered clinically important. At six months follow-up, the selenium group had increased rates of clinically important improvement (74% vs. 24% for placebo; P <0.001, NNT=2) and decreased rates of clinically important worsening (17% vs. 44%; P <0.001, NNT=3).
Selenium was also associated with higher rates of improvement in overall ophthalmologic assessment (61% vs. 36%; P <0.01, NNT=4). This difference was primarily due to significant improvements in eyelid aperture and soft-tissue signs in the selenium group. There were no significant differences in proptosis or eye-muscle motility. The improvements seen in the selenium group persisted at 12-month follow-up.
There were no significant differences between pentoxifylline and placebo in quality-of-life scores or ophthalmologic outcomes, but pentoxifylline was associated with increased risk of skin and GI adverse events.