ASSOCIATION BETWEEN OBESITY AND ALTERATIONS IN PHOTORECEPTOR–RETINAL PIGMENT EPITHELIUM–CHORIOCAPILLARIS COMPLEX IN HEALTHY EYES

Purpose: To investigate the effect of obesity on alterations in the photoreceptor–retinal pigment epithelium (RPE)–choriocapillaris complex. Methods: Two hundred and twenty participants with varying body mass index were enrolled and categorized into three groups: normal weight, overweight, and obese. Retinal and choroidal images were obtained using swept-source optical coherence tomography. Automatic segmentation was used for image analysis, evaluating retina thickness parameters such as retinal nerve fiber layer, ganglion cell layer and inner plexiform layer, inner nuclear layer, outer plexiform layer, outer nuclear layer, myoid and ellipsoid zone, outer segment of photoreceptors, RPE, and choroidal parameters including choroidal thickness, luminal area, stromal area, total choroidal area, choroidal vascular index, and choriocapillaris flow void percentage. Differences in photoreceptor–RPE–choriocapillaris complex among the groups and their correlation with body mass index were explored. Results: Compared with the control subjects, participants with obesity exhibited thinner myoid and ellipsoid zone and outer segment of photoreceptors, increased choriocapillaris flow void percentage, and thicker RPE. Correlation analysis revealed a negative correlation between body mass index and myoid and ellipsoid zone ( r = −0.17, P = 0.01) and outer segment of photoreceptors ( r = −0.16, P = 0.02), whereas a positive correlation was observed with RPE ( r = 0.15, P = 0.00). Conclusion: Individuals with obesity may present with a thinner myoid and ellipsoid zone and outer segment of photoreceptors, thicker RPE, and reduced choriocapillaris perfusion, suggesting potential damage to the photoreceptor–RPE–choriocapillaris complex. These alterations in the photoreceptor–RPE–choriocapillaris complex alterations could serve as potential biomarkers for monitoring early pathologic and physiologic changes associated with obesity.