Inner retinal structure and intraocular pressure in children with obesity

To test whether pediatric obesity is associated with inner retinal structure and intraocular pressure (IOP) changes, and whether insulin resistance (IR) is associated with additional ophthalmic differences within the obesity subgroup.

This cross-sectional study enrolled 202 children aged 6-18 years, including 92 with obesity and 110 controls. Both eyes underwent spectral-domain OCT to quantify peripapillary retinal nerve fiber layer (RNFL) and macular ganglion cell and inner plexiform layer (GCIPL) thickness; IOP was measured by rebound tonometry. Eye-level generalized estimating equation models accounted for inter-eye correlation and were adjusted for age and sex. Additional sensitivity analyses included axial length and spherical equivalent, and OCT-derived parameters were further assessed after axial length-related magnification correction. Within the obesity group, associations of IR status and selected routine biochemical markers with OCT and IOP parameters were explored.

In the primary age- and sex-adjusted models, obesity was associated with higher IOP and lower average, temporal, and nasal RNFL thickness. The adjusted IOP difference was 2.48 mmHg. After additional adjustment for axial length and spherical equivalent, the association with higher IOP remained robust, whereas RNFL differences were attenuated; only the temporal RNFL difference remained statistically significant. After magnification correction, RNFL differences no longer reached statistical significance. GCIPL thickness did not differ significantly between groups. Within the obesity subgroup, IR status and selected biochemical markers were not associated with additional OCT or IOP differences.

In this cross-sectional pediatric cohort, obesity was associated with higher IOP, and this association remained stable after adjustment for ocular biometry. RNFL differences were sensitive to biometry and magnification correction, whereas GCIPL thickness did not differ significantly. IR was not independently associated with OCT or IOP parameters within the obesity subgroup. Longitudinal studies are needed to determine the clinical relevance of these findings.