Changes in Inner Retina Thickness and Macular Sensitivity in Patients with Type 2 Diabetes with Moderate Diabetic Retinopathy

Ana Boned-Murillo; Guisela Fernández-Espinosa; Elvira Orduna-Hospital; Maria Dolores Díaz-Barreda; Ana Sánchez-Cano; María Sopeña-Pinilla; Sofía Bielsa-Alonso; Isabel Pinilla

doi:10.3390/biomedicines11112972

Changes in Inner Retina Thickness and Macular Sensitivity in Patients with Type 2 Diabetes with Moderate Diabetic Retinopathy

Biomedicines. 2023 Nov 4;11(11):2972. doi: 10.3390/biomedicines11112972.

Authors

Ana Boned-Murillo^{1

2

3}, Guisela Fernández-Espinosa¹, Elvira Orduna-Hospital^{1

4}, Maria Dolores Díaz-Barreda^{1

2

5}, Ana Sánchez-Cano^{1

4}, María Sopeña-Pinilla⁶, Sofía Bielsa-Alonso⁷, Isabel Pinilla^{1

2

7}

Affiliations

¹ Aragon Institute for Health Research (IIS Aragon), 50009 Zaragoza, Spain.
² Department of Ophthalmology, Lozano Blesa University Hospital, 50009 Zaragoza, Spain.
³ Department of Ophthalmology, Infanta Sofía University Hospital, 28703 Madrid, Spain.
⁴ Department of Applied Physics, University of Zaragoza, 50009 Zaragoza, Spain.
⁵ Department of Ophthalmology, Virgen de la Luz Hospital, 16002 Cuenca, Spain.
⁶ Department of Ophthalmology, Miguel-Servet University Hospital, 50009 Zaragoza, Spain.
⁷ Department of Surgery, University of Zaragoza, 50009 Zaragoza, Spain.

Abstract

The increase in diabetic retinopathy (DR) prevalence demonstrates the need for the determination of biomarkers for assessing disease development to obtain an early diagnosis and stop its progression. We aimed to analyse total retinal (RT) and inner retinal layer (IRL) thicknesses in type 2 diabetes mellitus (DM2) patients and correlate these results with retinal sensitivity using swept-source OCT (SS-OCT) and microperimetry. For this purpose, a total of 54 DM2 subjects with moderate diabetic retinopathy (DR) with no signs of diabetic macular oedema (DME) and 73 age-matched healthy individuals were assessed using SS-OCT to quantify retinal thickness in the nine macular areas of the ETDRS grid. Retinal sensitivity was measured via microperimetry with a Macular Integrity Assessment Device (MAIA). The mean ages were 64.06 ± 11.98 years for the DM2 group and 60.79 ± 8.62 years for the control group. DM2 patients presented lower visual acuity (p < 0.001) and a thicker RT (260.70 ± 19.22 μm in the control group vs. 271.90 ± 37.61 μm in the DM2 group, p = 0.01). The retinal nerve fibre layer (RNFL) was significantly lower in the outer nasal area (50.38 ± 8.20 μm vs. 45.17 ± 11.25 μm, p = 0.005) in ganglion cells and inner plexiform layers (GCL+) in DM2. A positive correlation between the LDL-C and RNFL and a negative correlation between HDL-C levels and the inner temporal and central RNFL thickness were detected. The central (p = 0.021) and inner nasal (p = 0.01) areas were negatively correlated between the RNFL and MAIA, while GCL++ was positively correlated with the outer inferior (p = 0.015) and outer nasal areas (p = 0.024). Retinal sensitivity and macular RNFL thickness decrease in DM2 patients with moderate DR with no DME, and this study enables an accurate approach to this disease with personalised assessment based on the DR course or stage. Thus, GCL+ and GCL++ thinning may support ganglion cell loss before the RNFL is affected.

Keywords: diabetic retinopathy; microperimetry; neurodegeneration; swept-source OCT; type 2 diabetes mellitus.

Grants and funding

This research was funded by the DGA group B08_20R: Investigación en Retina y Sistema Visual and Fondo Europeo de Desarrollo Regional (FEDER) funds: “Una manera de hacer Europa”, Instituto de Salud Carlos III (PI20/00740-FEDER).