Association between metabolic syndrome, macular structures and retinal vascular calibres in the Northern Finland Birth Cohort Eye Study

PURPOSE: We aimed to evaluate the association of metabolic syndrome (MetS) with macular thickness and retinal vascular calibres in the population-based cohort (Northern Finland Birth Cohort). METHODS: The population of 2242 individuals was divided into MetS (n = 344) and control groups (n = 1898). Cirrus HD-OCT 4000 was used to measure total macular thickness. Central retinal arteriolar equivalent (CRAE) and central retinal venular equivalent (CRVE) were calculated from the fundus images. The MetS was defined according to the National Cholesterol Education Program (Adult Treatment Panel III). RESULTS: A significant reduction in macular thickness was observed in subjects with MetS (279.4 ± 13.5 vs. 282.2 ± 14.1 μm, p < 0.001); the difference was greatest in the nasal and inferior subfields in the outer perimeter (-3.18 μm, p < 0.001 and - 3.68 μm, p < 0.001). Among the MetS components, waist circumference (WC) was particularly associated with thinning of the macula. Furthermore, subjects with MetS displayed decreased CRAE (139.8 ± 13.2 vs. 141.8 ± 14.0 μm, p = 0.014) and increased CRVE (221.7 ± 20.5 vs. 218.3 ± 19.0 μm, p = 0.007). The elevated systolic blood pressure and WC were associated with arterial narrowing, while dyslipidemia, hypertriglyceridemia and low HDL cholesterol were associated with venular widening. CONCLUSION: We detected a thinning of the macula in the MetS in our population-based cohort. The diameters of the retinal arteries decreased, and the venules increased in MetS. These findings suggest that obesity is related to structural changes in the eyes in middle-aged subjects, which may have implications for ocular health.