Specific weight loss medications may also benefit ocular outcomes

A study recently published in Communications Medicine evaluated the ocular health outcomes in obese individuals receiving anti-obesity medications.

Give me some background.

Obesity affects over 1 billion people worldwide, with adult obesity rates doubling since 1990 and childhood and adolescent obesity rising from 8% in 1990 to 20% in 2022.

As a complex metabolic disorder, obesity is associated with numerous comorbidities, including:

Cardiovascular diseases
Type 2 diabetes
Various ocular complications, such as cataracts, diabetic retinopathy, age-related macular degeneration (AMD), glaucoma, and dry eye disease (DED)

And on the anti-obesity front?

Novel anti-obesity medications, such as tirzepatide and semaglutide, have demonstrated greater weight loss efficacy than traditional medications.

However: The study authors noted that direct comparisons of the ocular effects of anti-obesity medications remain limited.

Now talk about the study.

In this propensity-score matched (PSM) cohort study, investigators utilized the TriNetX platform to include matched pairs of obese individuals with a body mass index (BMI) ≥ 27 kg/m² and compare ocular outcomes between different anti-obesity medications.

Participants were included if they initiated any of the following anti-obesity medications listed below from November 2023 to April 2025.

Tirzepatide
Semaglutide
Phentermine / Topiramate (Qsymia)
Naltrexone / Bupropion (Contrave)
Phentermine

And the primary outcomes?

They were as follows:

Cataracts
Oculomotor binocular dysfunction
Visual disturbances
DED
Ametropic accommodative dysfunction
Visual issues with blindness

In addition: Sensitivity analyses included:

Populations with BMI ≥ 30 kg/m²
Subgroup stratification by clinical characteristics
Negative control outcomes to assess residual bias

Findings?

In total, 100,412 eligible individuals taking anti-obesity medications were included and subjected to 1:1 PSM for pairwise comparative analyses.

Of the 25,060 matched pairs comparing tirzepatide with semaglutide, no differences were shown in regard to ocular outcomes.

I’m sensing a but …

When compared with naltrexone / bupropion, tirzepatide users demonstrated lower rates of:

Cataracts (hazard ratio [HR]: 0.46, 95% confidence interval [CI]: 0.23-0.92, p = 0.025)
Oculomotor dysfunction (HR: 0.31, 95% CI: 0.16-0.60, p = 2.3 x 10-⁴)

Anything else?

Both semaglutide and tirzepatide showed favorable profiles in terms of visual disturbances and DED compared to older medications.

For instance:
- Tirzepatide exhibited lower rates of visual disturbances than phentermine (HR: 0.45, 95% CI: 0.31-0.68, p = 7 x 10^-5).
Semaglutide was associated with a lower incidence of DED compared to both phentermine / topiramate (HR: 0.26, 95% CI: 0.13-0.50, p = 2 x 10^-5) and naltrexone / bupropion (HR: 0.36, 95% CI: 0.18-0.73, p = 0.003).

How about in terms of sensitivity?

Sensitivity analyses in the BMI ≥ 30 kg/m² population yielded consistent results.

Meaning: Medication choice in obesity management may have implications beyond metabolic benefits to include ocular health considerations.

So what was the expert opinion?

In this study, semaglutide was consistently associated with lower rates of visual disturbances across all comparisons.

Meaning: “Glucagon-like peptide 1 (GLP-1) receptor activation may influence not only metabolic parameters, but also neural pathways involved in visual processing and oculomotor control, though the precise mechanisms require further investigation,” the study authors explained.

Related: Check out the American Optometric Association’s latest report on GLP-1 use and ophthalmic risks.

Noted. Any limitations to consider?

A few. These included:

Unmeasured confounders, particularly lifestyle factors like dietary patterns, physical activity levels, smoking status, and alcohol consumption could have influenced treatment selection and ocular outcomes
There may have been treatment selection bias by clinicians based on unmeasured clinical factors
Tirzepatide’s relatively recent U.S. market entry resulted in smaller sample sizes, potentially reducing power to detect subtle ocular changes
International Classification of Diseases, Tenth Revision (ICD-10) coding may have missed subclinical or undiagnosed early-stage ocular conditions

Tie it all together for me.

These findings demonstrate that newer anti-obesity medications were associated with more favorable ocular safety profiles compared to traditional treatments.

For example: Tirzepatide users had almost half the risk of cataracts compared to those taking naltrexone / bupropion.

As such: Prospective studies are necessary to establish causal relationships between these medications and ocular health outcomes.