BACKGROUND
Graves’ disease is the most common cause of hyperthyroidism in the United States. Graves’ disease is caused by the body making antibodies that attack the thyroid and turn it on, causing the thyroid gland to make too much thyroid hormone. These antibodies can also affect the eyes, causing inflammation of the eyes, eye muscles and the surrounding tissues. Symptoms include dry eyes, red eyes, bulging of the eyes and double vision. This is known as thyroid eye disease (TED). TED develops in 25 to 40% of patients with Graves’ disease, particularly during the first 1 to 2 years following the onset of the hyperthyroidism. Until recently, TED has been very difficult to treat, as usually anti-inflammatory medications were not that effective. Currently, there are several medications that can help remove the antibodies and markedly improve symptoms of TED.

Statins are widely prescribed drugs that lower cholesterol. Multiple studies have shown that statins have antiinflammatory effects and may be able to interfere with the immune response. Because of these properties, prior studies have suggested that they may reduce the risk of developing TED. However, it is unknown whether the timing of starting statin drugs after the onset of Graves’ disease affects this association. This study aimed to determine whether starting statins early or whether the start is delayed affects the risk of developing TED in a large nationwide group.

THE FULL ARTICLE TITLE
Chou YT et al. Early statin use following diagnosis of Graves’ disease is associated with a reduced risk of moderate- to-severe Graves’ orbitopathy in middle-aged adults: evidence from a nationwide Taiwanese cohort. Thyroid. 2025;35(9):1052-1062;

SUMMARY OF THE STUDY
This study used Taiwan’s National Health Insurance Research Database (2009–2019). Adults over 40 years newly diagnosed with Graves’ disease were included, while patients with prior lipid-lowering therapy, preexisting TED, or insufficient follow-up were excluded.

Statin users were defined as those prescribed statins ≥2 times over 6 months. A control group included nonusers of statins. Participants were stratified into three groups based on timing of starting the statin: within 1 year (group A), 1 to 2 years (group B), and 2–3 years (group C) after Graves’ disease diagnosis. TED was classified as mild or moderate to severe based on treatment received.

The study included 47,424 Graves’ disease patients (4649 statin users and 18,584 nonusers in group A, 3060 users and 12,349 nonusers in group B, and 1752 users and 7030 nonusers in group C). Over an average follow-up of 4 to 5 years, group A statin users had a 34% lower risk of total TED and a 61% lower risk of moderateto- severe TED compared with nonusers. No significant reduction was observed for mild TED. Importantly, no protective effect was observed in group B or C, indicating that timing of beginning statin drugs was crucial. The benefit was most pronounced in middle-aged patients, nonsmokers, and those without prior radioiodine therapy or thyroidectomy. Statin type and dose did not significantly affect outcomes.

WHAT ARE THE IMPLICATIONS OF THIS STUDY?
This study suggests that beginning stating drugs early, preferably within 1 year after Graves’ disease diagnosis, significantly reduces the risk of moderate-to-severe TED, whereas later initiation does not. Timing, rather than statin type or dose, appears critical. This data needs to be confirmed in additional studies, but do suggest that statins are effective in preventing the onset of TED in patients with Graves’ disease.

— Alan P. Farwell, MD

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