Ocular Manifestations of Metabolic Syndrome: A Systemic Vascular Phenotype

Metabolic syndrome (MetS) is defined by central obesity, insulin resistance, hypertension and dyslipidemia. MetS affects over one-third of US adults. Beyond its cardiovascular burden, MetS has clinically relevant associations with ocular health and may contribute to a systemic vascular and neuro-metabolic phenotype involving the retina, optic nerve, lens, ocular surface and choroid.

This narrative review searched PubMed through May 2026 using combinations of free-text and MeSH-based terms related to 'metabolic syndrome', 'insulin resistance', 'obesity', 'hypertension', 'dyslipidemia', 'diabetes', 'diabetic retinopathy', 'diabetic macular edema', 'glaucoma', 'cataract', 'dry eye', 'macular degeneration', 'retinal vascular occlusion' and 'optic neuropathy'. Reference lists of relevant reviews and primary studies were also screened. English-language human, translational, epidemiologic, clinical-trial, systematic-review and meta-analysis articles were prioritized. This was not designed as a systematic review, and formal PRISMA screening, risk-of-bias grading and meta-analysis were not performed.

MetS and its components are associated with diabetic retinopathy, diabetic macular edema (DME), non-diabetic retinopathy, primary open-angle glaucoma, cataract, dry eye disease, age-related macular degeneration (AMD), retinal vascular occlusions and non-arteritic anterior ischemic optic neuropathy (NAION). Shared mechanisms include chronic inflammation, oxidative stress, endothelial dysfunction, insulin resistance-driven retinal neurodegeneration, dyslipidemia-related lipotoxicity, hypertension-related microvascular injury and microvascular rarefaction. Management requires both systemic risk-factor optimization and disease-specific ophthalmic therapy, including anti-VEGF therapy, intraocular pressure reduction, laser or surgical procedures when indicated, ocular surface-directed therapy and cataract surgery when visually significant.

Ocular complications associated with MetS are common and may be vision-threatening. Risk-based ocular surveillance and metabolic optimization are justified, particularly in patients with diabetes, hypertension, dyslipidemia, visual symptoms or established vascular disease. However, the strength of disease-specific evidence varies: interventional evidence is strongest for diabetic retinopathy risk reduction and glaucoma treatment through intraocular pressure lowering, whereas evidence for AMD, NAION, RVO, cataract and dry eye disease is more frequently observational or indirect.