Vnitr Lek 2026, 72(4):E1-E3 | DOI: 10.36290/vnl.2026.053

Type 2 diabetes mellitus + glaucoma = type 4 diabetes mellitus

Štefan Sotak
KATOS MED, s. r. o., Humenné

The term "type 4 diabetes mellitus (DM)" is not generally recognized. It occurs more in popular science than in professional science literature. However, it is interesting that this term has two meanings, two different definitions. The first definition of this type of diabetes is that it is a type 2 DM that occurs in patients with glaucoma. Although the relationship between any type of glaucoma and any type of DM has been debated in the past, cumulative epidemiological evidence confirms that the risk of developing glaucoma, specifically primary open-angle glaucoma, is increased in the diabetic population. Other types of glaucoma in diabetes have not been studied. Type 4 DM is not understood as a separate type of diabetes, but rather as a collective name for two different diseases, between which there is most likely a connection.

Keywords: type 4 diabetes mellitus, primary open-angle glaucoma, insulin resistance, blindness.

Accepted: June 11, 2026; Published: June 24, 2026  Show citation

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Sotak Š. Type 2 diabetes mellitus + glaucoma = type 4 diabetes mellitus. Vnitr Lek. 2026;72(4):E1-3. doi: 10.36290/vnl.2026.053.
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