TOPLINE

Women who received menopausal hormone therapy had higher risks for new diagnoses of strabismus and strabismus surgery than women who did not receive the therapy. Moreover, researchers detected estrogen receptor alpha in the extraocular muscle of a donor.

METHODOLOGY

• Researchers conducted a retrospective clinical cohort study using data from a large electronic health record database to assess the association between the use of hormone therapy and strabismus outcomes.
• The analysis included more than 2.15 million women first diagnosed with menopause at 44-60 years of age between January 2010 and October 2025.
• Hormone therapy was defined as the prescription of estrogen-only or combined estrogen-progestin therapy at least 90 days after menopause. Overall, 9.2% of women received hormone therapy, and 90.8% did not.
• The outcomes included a new diagnosis of strabismus, first-time strabismus surgery, and reoperation after surgery, excluding cases of congenital, mechanical, genetic, neurologic, paralytic, and traumatic strabismus. Follow-up continued until the relevant event or the end of the study. 
• Researchers examined a sample of extraocular muscle from a 74-year-old deceased female donor and used microscopy to detect the presence of estrogen receptor alpha. 

TAKEAWAY

• Women who received hormone therapy had an 11% higher risk for a new diagnosis of strabismus (P = .015) and a 76% higher risk for strabismus surgery (P < .001) than women who did not receive the therapy.
• The use of hormone therapy was not associated with an increased risk for reoperation after strabismus surgery.
• Starting hormone therapy 3 to less than 10 years after menopause was associated with a 29% higher risk for a diagnosis of strabismus than starting the therapy within 3 years (P = .046). Each additional year of delay was linked to a 7% increased risk (P = .005).
• Researchers detected clear expression of estrogen receptor alpha in the sample of eye muscle of the donor.

IN PRACTICE

“These findings provide important preliminary insights regarding the potential relationship between sex hormones and ocular alignment,” the researchers of the study reported.

SOURCE

The study was led by Akshara R. Legala, University of California, San Diego. It was published online on July 1 in the American Journal of Ophthalmology.

LIMITATIONS

The source database was subject to miscoding, variation in practice, and missing data. The study was retrospective and could not establish that hormone therapy caused the outcomes. Care outside the database or before its integration into electronic health records may have been missed.

DISCLOSURES

The study received support from Research to Prevent Blindness and from the National Institutes of Health. Several authors reported receiving grants from nonprofit vision foundations and government agencies, consulting fees from pharmaceutical and biotechnology firms, royalties from medical publishers, and support from national career-development programs. Detailed disclosures are available in the original article.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.