Retinal thinning may foreshadow neurodegeneration in SLE

Patients with systemic lupus erythematosus (SLE) show progressive reduction in the thickness of peripapillary retinal nerve fibre layer (pRNFL), suggestive of early neurodegeneration, a recent study has found.

The researchers conducted a prospective cohort study of 68 previously diagnosed SLE patients (mean age 45.50±12.67 years, 85.3 percent women) who underwent a complete ophthalmologic examination including spectral domain-optical coherence tomography. Such evaluations were performed in two study visits (V1 and V2) at least 12 months apart and were accompanied by autoimmune assessments.

Patients had had SLE for a median duration of 11.0 years and had been treated with hydroxychloroquine for a median of 5.3 years. At enrolment and throughout the study, all patients were clinically stable with low disease activity.

At V1, the mean global pRNFL thickness was 96.59±10.68 µm, which dropped significantly to 95.91±10.01 µm at V2 (p=0.006). Such a reduction seemed to be driven mostly by pRNFL thinning in the temporal inferior region (141.85±19.89 to 140.48±19.79 µm; p=0.017), and to a lesser degree the nasal inferior region (113.93±25.56 to 112.82±25.13 µm; p=0.053).

In contrast, pRNFL thickness in the temporal superior, temporal, nasal, and nasal superior regions showed no significant changes between V1 and V2.

“These microstructural changes might relate to chronic low-grade inflammation, leading to neuronal apoptosis, which are the hallmarks of neurodegeneration,” the researchers said, however pointing out that the magnitude of pRNFL thinning is small.

“Future studies with longer follow-up periods are needed to confirm the progressive nature of retinal structural changes and to relate them with structural and functional changes in central nervous system imaging,” they added.