Retinal thickness changes in preobese and obese patients without hyperglycemia: Optical coherence tomography study

Area of Science:

• Ophthalmology
• Metabolic Health
• Retinal Imaging

Background:

• Obesity is a global health concern linked to various systemic complications.
• Retinal changes can serve as an indicator of metabolic disturbances.
• Previous research has explored the link between obesity and diabetic retinopathy, but less is known about retinal thickness in non-hyperglycemic individuals with varying body mass index (BMI).

Purpose of the Study:

• To investigate the relationship between preobesity, obesity, and retinal thickness using optical coherence tomography (OCT).
• To determine if body mass index (BMI) alone, in the absence of hyperglycemia, influences retinal structure.
• To explore the potential role of lipid metabolism in observed retinal changes.

Main Methods:

• A comparative cross-sectional study involving 131 participants categorized into normal weight (BMI 18.5-24.9 kg/m2), preobese (BMI 25-29.9 kg/m2), and obese (BMI >30 kg/m2) groups.
• Exclusion of participants with hyperglycemia after fasting serological biochemical and lipid tests.
• Comprehensive ophthalmological examination including sectoral retinal analysis via optical coherence tomography (OCT).

Main Results:

• Central foveal thickness was significantly higher in the preobese group and lower in the obese group compared to normal weight individuals.
• Mean inferior retinal thickness within the Early Treatment Diabetic Retinopathy Study (ETDRS) circle was significantly elevated in the preobese group and reduced in the obese group.
• While nasal, temporal, and superior retinal thicknesses, as well as peripapillary retinal nerve fiber layer, showed trends of increase in preobesity and decrease in obesity, these differences were not statistically significant.

Conclusions:

• Preobesity, even without hyperglycemia, is associated with increased central macular thickness.
• Obesity is linked to retinal thinning, suggesting that lipid metabolism alterations can independently affect retinal thickness.
• These findings underscore the potential for metabolic dysregulation to contribute to retinal neurodegeneration.