Obesity-related early structural alterations in the retina detected by optical coherence tomography.

AIMS: This retrospective cross-sectional study, using retinal spectral-domain optical coherence tomography (SD-OCT) scans, investigated obesity-related structural alterations in the retina.

MATERIALS AND

METHODS

Ninety-two eyes of 92 healthy asymptomatic participants were categorized into two groups based on body mass index (BMI) measurements: non-obese (BMI < 25, 45%) and pre-obese/obese (BMI ≥ 25, 55%) to compare imaging parameters of different retinal layers. Structural parameters, including thickness and volume values, were obtained across distinct retinal layers segmented on SD-OCT scans.

RESULTS

The retinal nerve fibre layer volume was lower in the high-BMI group than in the low-BMI group (p = 0.048). However, the high-BMI group presented significantly higher inner nuclear layer volume than the low-BMI group (p = 0.036). In the region analysis, the retinal nerve fibre layer volume difference was prominent in the superior (p = 0.033) and inferior (p = 0.001) parafoveal and nasal perifoveal (p = 0.041) regions, while inner nuclear layer changes were prominent in the inferior (p = 0.009) perifoveal regions. A stepwise hierarchical binary logistic regression model, controlling for age and gender, pointed to significant associations of the regionally decreased retinal nerve fibre layer volume and increased inner nuclear layer volume with high BMI (p = 0.001).

CONCLUSIONS

Retinal SD-OCT imaging detected structural alterations in distinct retinal layers between healthy, asymptomatic individuals in non-obese and pre-obese/obese groups. Besides a decreased volume of the retinal nerve fibre layer, a significant increase was detected in the inner nuclear layer volume with a high BMI, possibly due to Müller glia responses to obesity-related osmotic, metabolic and inflammatory stress, awaiting further investigation.